Dissertations / Theses on the topic 'Stocking density'

Stocking density serves as a sub-clinical stressor impacting natural behavior and affective state of dairy cows. However, cows rarely experience stocking density as an isolated stressor. Understanding the effects of stocking density with additional management stressors such as low-fiber diets or feed restriction is the next step in alleviating stress and improving the well-being of lactating dairy cows housed in freestall barns. The overall goal of this dissertation was to evaluate the interaction of stocking density and the feeding environment on short-term production, behavioral, ruminal fermentation, and stress responses of lactating dairy cattle. The first two studies (Chapter 2 and 3) served as preliminary research for the main studies of this dissertation. The first study objective was to evaluate the effectiveness of using chopped wheat straw to reduce sub-acute ruminal acidosis (SARA) in order to formulate diets for the first main study. Treatments were low straw (0 kg dry matter (DM)/d; LS) and high straw (1.36 kg DM/d; HS). High straw appeared to effectively reduce SARA by lowering time below pH 5.8 with minimal impact on feed intake and rumination. The second study objective was to evaluate the effect of type of blood collection tube on haptoglobin concentration across two commercially-available haptoglobin assays and evaluate assay agreement in order to determine haptoglobin concentrations for the main studies. Lithium heparinized, sodium heparinized, and K2-EDTA plasma resulted in increased haptoglobin concentrations compared to serum using the Tri-Delta colorimetric assay, but no differences were observed using the Life Diagnostics ELISA assay. However, there was a lack of agreement between assays and further identification of a gold-standard assay is needed before analyzing haptoglobin for the main studies. The third study (Chapter 4) investigated the interaction of stocking density (100% and 142% of freestalls and headlocks) and source of forage fiber (no added straw and added straw at 3.5% ration DM). Treatments did not impact feed intake, but straw diets tended to reduce milk production. Increasing stocking density reduced lying time but increased efficiency of stall use. Though feeding and rumination times were unaffected, overstocking shifted the location of rumination away from the freestall. Increased stocking density tended to increase stress responses. Both greater stocking density and no straw diets increased SARA, and the combination of these stressors tended to exacerbate this pH response. Adding straw to the diet reduced the negative impacts of overstocking on ruminal pH. The fourth study (Chapter 5) evaluated the interaction of stocking density (100% and 142%) and feed access (5-h reduced feed access and no reduced feed access). Treatments had minimal impact on short-term feed intake and production. Overstocking affected behavior similar to responses observed in Chapter 4. Reducing feed access decreased feeding time, though cows altered feeding and rumination responses to maintain daily rumination. Both treatments shifted priorities for feeding and lying behavior, though increased stocking density had the larger impact. Though reduced feed access did not impact ruminal pH, an exacerbated response was observed when combined with increased stocking density. The combination of stocking density and feeding environment stressors exacerbate negative effects on biological function and should be avoided.

The profitability of abalone farms is heavily influenced by their production per unit of grow-out space. With farms having physically expanded to the maximum, and with increasing production costs, one of the most realistic ways for farms to increase their production is through optimizing stocking densities. The effect of stocking density on Haliotis midae performance is undocumented and optimal stocking densities for this species have not been determined. Experiments were conducted under farm conditions to investigate the effects of four different stocking densities (16 %, 20 %, 22 % and 24 % of available surface area) on growth, production and health of three different size classes of abalone (15-35 g, 45-65 g, and 70-90 g start weight). Each treatment was replicated four times and trials ran over a period of eight months with measurements being made at four month intervals. Abalone behaviour was observed during the trials in the experimental tanks. Weight gain per abalone decreased with an increase in density for all tested size classes (5.04 ± 0.18 to 2.38 ± 0.17; 5.35 ± 0.21 to 4.62 ± 0.29; 7.97 ± 0.37 to 6.53 ± 0.28 g.abalone-1.month-1 for the 15-35, 45-65 and 70-90 g classes respectively, with an increased density of 16 to 24 %). Individual weight gain of 15-35 g abalone was similar at stocking densities of 16 % and 20 % while weight gain of 45-65 g and 70-90 g abalone decreased when density was increased above 16 %. Biomass gain (kg.basket-1.month-1) was not affected by stocking density in the 15-35 g and 45-65 g size classes (1.29 ± 0.02 and 0.97 ± 0.02 kg.basket-1.month-1 respectively). However, the biomass gained by baskets stocked with 70-90 g abalone increased with stocking density (1.08 ± 0.02 to 1.33 ± 0.02 kg.basket-1.month-1) with an increased density of 16 to 24 %) and did not appear to plateau within the tested density range (16 to 24 %). Food conversion ratio did not differ significantly between densities across all size classes. Stocking density did not have a significant effect on abalone condition factor or health indices. The proportion of abalone above the level of the feeder plate increased with density (7.26 ± 1.33 to 16.44 ± 1.33 with an increased density of 16 to 24 %). As a proportion of abalone situated in the area of the basket, the same proportions were situated on the walls above the feeder plate and on the feeder plate itself irrespective of stocking density (p > 0.05). Higher proportions of animals had restricted access to feed at higher stocking densities (p = 0.03). The amount of formulated feed available on the feeder plate did not differ between stocking densities throughout the night (p = 0.19). Individual abalone spent more time above the feeder plate at higher stocking densities (p < 0.05). The percentage of time above the feeder plate, spent on the walls of the basket and on the feeding surface was not significantly different at densities of 20 %, 22 % and 24 % (p > 0.05) but abalone stocked at 16 % spent a greater percentage of time above the feeder plate on the feeding surface (83.99 ± 6.26 %) than on the basket walls (16.01 ± 6.26 %). Stocking density did not affect the positioning of abalone within a basket during the day or at night. Different size H. midae are affected differently by increases in stocking density in terms of growth performance. Findings from this research may be implemented into farm management strategies to best suit production goals, whether in terms of biomass production or individual weight gain. The fundamental mechanisms resulting in reduced growth at higher densities are not well understood, however results from behaviour observations suggest that competition for preferred attachment space and feed availability are contributing to decreased growth rates. With knowledge of abalone behaviour at different densities, innovative tank designs may be established in order to counter the reduction in growth at higher densities.

Stocking grass carp Ctenopharyngodon idella is a commonly applied technique used to control nuisance aquatic vegetation in reservoirs. Factors that influence the degree of aquatic vegetation control are stocking density, regional climate, abundance and species composition of the aquatic plant community, and relative grass carp feeding preferences for the plant species. We evaluated high-density grass carp stocking in a reservoir for control of parrot-feather (Myriophyllum aquaticum, an invasive aquatic plant that is not preferentially consumed by grass carp) and the associated effects on water quality and native fishes. Lookout Shoals Lake, a piedmont North Carolina reservoir, was stocked with triploid grass carp at a density of 100 fish per vegetated hectare. Parrot-feather biomass in the lake was significantly reduced three months after grass carp stocking, compared to biomass in in-situ exclosures. During the second year after grass carp stocking, parrot-feather biomass in the lake compared to biomass in in-situ exclosures indicated continued control, but unexplained lack of growth within most experimental exclosures precluded biomass analyses. Increases in ambient water chlorophyll a, reactive phosphorus, and nitrate-nitrite concentrations were measured after grass carp stocking. We evaluated the native fish community using seasonal shoreline electrofishing before and after grass carp stocking. Total catch for all fish species in aggregate at shoreline transects was not significantly different after grass carp stocking by number or biomass. Catch rates of largemouth bass Micropterus salmoides, bluegill Lepomis macrochirus, and redbreast sunfish Lepomis auritus were not significantly different after grass carp stocking, but yellow perch Perca flavescens catch rates were significantly lower. The biological significance of fish distribution changes and long-term effects on lake biota remain undetermined. Our results demonstrate that intensive grass carp stocking can control an invasive aquatic plant that is not preferentially consumed by grass carp, and reveal associated changes in water quality and fish distributions.

The objective of these studies was to determine the effects of forage fiber, social hierarchy, and stocking density on stress in lactating cows during relocation to new dairy facilities. In experiment one, 23 lactating cows were fed a basal ration, or the basal ration plus grass or alfalfa hay at 10% of DM offered from 3 wk pre-move to 9 wk post-move. In experiment two, 17 lactating cows were housed together before and after relocation and evaluated for dominance rank. In experiment three, 44 cows were housed together before relocation, then in pens of varying stocking density (0.67, 0.83, 1.0, or 1.17 cows per stall) post-move. In these studies, the effects of treatment on MY, lameness, behaviors, plasma cortisol, cow cleanliness, and DMI were monitored. In experiment one, cows fed grass or alfalfa hay diets had higher plasma cortisol concentrations on the day of relocation than cows fed TMR, but there were no differences in DMI or MY. Cows fed alfalfa hay or TMR had increased lameness scores following relocation; cows fed grass hay did not have increased lameness scores. In experiment two, there were no differences in plasma cortisol or lameness scores between dominant and subordinate cows. Subordinate cows had lower MY following relocation compared to dominant cows. In experiment three, cows housed at a stocking rate of 1.17 had higher plasma cortisol than cows housed at a stocking rate of 0.67. All cows had higher lameness scores following relocation, but cows housed at a stocking rate of 0.67 tended to have higher lameness scores than cows housed at stocking rates of 0.83, 1.0, and 1.17. In summary, some management practices may decrease the negative effects of stress on lactating cows during relocation.
Master of Science

In aquaculture, a thorough knowledge of the specific environmental requirements of a species is needed in order to maximize growth rate and survival. There is a paucity of data regarding the fundamental environmental requirements for the ongrowing phase of clownfish juveniles. This prompted the design of three experiments to determine the best feeding regimen, temperature and stocking density that maximize growth and survival of Amphiprion percula. Ration size and feeding frequency are important factors for optimizing fish growth during the juvenile grow-out phase. A factorial growth trial was conducted to determine the effect of feeding frequency and ration size on the growth of juvenile clownfish (Amphiprion percula).Three feeding frequencies (1, 2 and 3 times daily) and six rations (2,4,6,8, 10 and 12 % body weight per day (BW.day⁻¹)) were used to test the growth response over a twelve week period. Non-linear regression analysis on the effect of ration, independent of feeding frequency, on growth resulted in a significant (n = 36; r² = 68.7) parabolic model: In y = -0.0302x² + 0.5159x + -4.4377. Maximum growth corresponded to a ration of 8.5% BW.day⁻¹. Survival as a function of ration was significantly lower at 2% BW.day⁻¹. Data were further examined with Analysis of CoVariance (ANCOVA) to determine the effect of ration on growth at each feeding frequency. The combination revealed a maximum growth rate when the fish were fed a ration of 10% BW.day⁻¹ divided into two equal meals. The required ration per meal to maintain maximum growth was also found to decrease as feeding frequency increased. The determination of the best temperature for growth is of great importance due to the direct relationship between fish metabolism and temperature. The thermal preferendum of A. percula has already been estimated at 26 ± 0.7°C but it is not known whether this closely approximates the temperature for maximum growth. Sixteen tanks were set to different temperatures ranging between 21.5 and 30.2 °C. Ten juvenile A. percula were placed in each tank and growth was measured fortnightly over the course of the 10 week experiment. Non-linear regression analysis resulted in significant models for fish length (y = -0.0005x² + 0.00267x - 0.0338; r² = 56.7, n = 11) and weight (y= -0.00016x² + 0.0084x - 0.1073; r² = 61.6, n = 11). These models predict that maximum growth would be at 27.7 and 27.1 °C for length and weight, respectively. Temperature, over the range tested, had no apparent effect on survival. There was no significant difference between the temperatures for maximum growth and the preferred temperature. The effect of stocking densities ranging from 0.2 fish.L¹ to 4.0 fish.L⁻¹ on growth were used in the third experiment. The fish were fed to satiation twice daily and growth was measured fortnightly throughout the 8 week experiment. No effects on growth, survival or coefficient of variation were found within the range of stocking densities tested.

In commercial settings, broiler chickens and rainbow trout are housed in barren environments under high stocking densities, due to an emphasis on production efficiency. These monotonous housing conditions do not provide broilers or trout with the ability to perform functional, highly-motivated behaviors and increase their susceptibility to excessive anxiety and fear, resulting in negative affective states and poor animal welfare. Affective state (or emotional state) is a cumulative product of short-term life experiences, ranging from positive to negative. Because affective states are largely influenced by environmental condition, determining animal affective state can provide useful information on how to improve housing conditions in order to ensure positive experiences and good animal welfare. Cognitive processes are closely associated with affective state; a "cognitive bias" occurs when affective state influences aspects of cognition, such as judgement and attention. Animals in positive affective states make optimistically-biased decisions during ambiguous situations, judging the situation as if it will produce a positive outcome, and show less bias towards a perceived threat, responding in a less anxious and calm manner. Animals in negative affective states make pessimistically-biased decisions during ambiguous situations, judging the situation as if it will result in a negative outcome. Additionally, animals in negative affective states will bias their attention towards a perceived threat rather than alternative stimuli, responding in an anxious manner. Therefore, judgement and attention bias tests can be used to determine animal affective states. In Chapter 3, a judgement bias test was used to determine affective state of broiler chickens housed in either complex (perches, dust bath, pecking stones, and rotating enrichment objects) or barren (no enrichment) environments under either high or low stocking densities. Broilers housed in complex environments responded more optimistically during the judgement bias test than broilers from barren environments, indicating the former were in a positive affective state. Stocking density did not impact their responses in the judgement bias test, indicating that affective states were not impacted by that treatment. In Chapter 4, an attention bias test was used to determine level of anxiety and a tonic immobility test was used to determine fear in order to investigate affective state of broilers housed in the same conditions as described for Chapter 3. Broilers housed in complex environments were less anxious during the attention bias test than broilers from barren environments, indicating environmental complexity reduced anxiety in broilers. Stocking density did not impact anxiety. Broilers from high stocking density environments had shorter tonic immobility durations than broilers from low stocking density environments, suggesting the former were less fearful. Environmental complexity did not impact fearfulness. In Chapter 5, a judgement bias test was used to determine affective state of rainbow trout housed in either complex (shelter structure and artificial plants) or barren (no enrichment) tanks under either low or high stocking densities. Trout housed in high stocking density tanks responded optimistically during the judgement bias test, indicating they were in a more positive affective state compared to trout housed in low stocking density tanks. Environmental complexity did not impact their responses in the judgement bias test, indicating no effect of enrichments on affective states was found. These results indicate a beneficial relationship of a complex environment on broiler chicken affective state, observed through an optimistic judgement bias and reduced attention bias (anxiety) towards a perceived threat. Thus, providing a complex housing environment for broilers can improve their welfare and result in a positive affective state. Rainbow trout reared at the tested high density resulted in a positive affective state, although complexity did not benefit their welfare. Our results contribute much needed information on stocking densities to ensure fish welfare. Overall, environmental complexity, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental complexity.
Master of Science
Conventional housing of broiler chickens and rainbow trout (both raised for meat) causes concern for their welfare and affective states. Environmental conditions can greatly impact animals' affective states–their long-term emotional state, ranging from positive to negative. In barren environments at high stocking densities, broiler chickens and rainbow trout are prevented from showing normal behaviors and these conditions can compromise their affective state and welfare. By 'asking' chickens and trout whether the glass is half full or half empty, we can determine level of optimism or pessimism, and level of anxiety or calmness, therefore gaining a better understanding of their affective states. This can be done using a judgement bias test and attention bias test, where animal responses (optimism and anxiety) are recorded during ambiguous situations (judgement) and threatening situations (attention). Animals in positive affective states judge ambiguous situations optimistically (glass half full) and pay little attention towards perceived threats, while animals in negative affective states judge the same ambiguous situations pessimistically (glass half empty) and pay more attention towards perceived threats. In Chapter 3, responses to ambiguous situations were used to determine the affective state of broiler chickens housed in either enriched (perches, dust bath, pecking stones, rotating toys) or barren environments at either high or low stocking densities. Broiler chickens housed in enriched environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state compared to broilers housed in barren environments. Stocking density did not impact their level of optimism. In Chapter 4, responses to a perceived threat were used to determine level of anxiety and a tonic immobility test was used to determine fear of broilers housed under the same conditions as in Chapter 3. Broilers housed in enriched environments paid less attention to a perceived threat than broilers housed in barren environments, indicating the former were less anxious (glass half full) and in a positive affective state. Fear was not impacted by the tested enrichments, but birds kept under higher stocking densities did show reduced fear compared to birds in low-density environments. In Chapter 5, rainbow trout were housed in either enriched (shelter structure and artificial plants) or barren tanks at either high or low stocking densities. Affective state was evaluated through their responses to ambiguous situations. Trout housed in high stocking density environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state than trout housed in low stocking density environments. The enrichments did not impact their responses during the test, suggesting they did not impact fish optimism. These results indicate that an enriched environment improves broiler affective state and welfare compared to conventional housing conditions, the tested densities did not impact their welfare. Although an enriched environment did not positively impact responses of trout during ambiguous situations, our results show that housing rainbow trout in large groups results in a positive affective state and improved welfare status compared to housing trout in small groups. Overall, environmental enrichment, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental enrichment.

There has been a continuous decline in both the production and general performance of the SRO in NSW estuaries over the past three decades. The relationship of this decline to both environmental and oyster-density related factors are assessed in this thesis. This question has been examined at different scales: a large scale that compares two different estuaries (Clyde and Shoalhaven Rivers, southern NSW); a regional scale that encompasses variations within an estuary and, at a lease scale that examines processes pertaining to individual or small groups of oysters. Levels of inorganic nutrients were in general very low potentially limiting primary production. The limiting nutrient was nitrogen or phosphorus depending on whether long term conditions were dry or wet, respectively. Only during rain events, through the input of terrestrial material, were conditions favourable for fast rates of primary production. Carbon and nitrogen isotope analysis has demonstrated that both external material and local resuspension of the benthos constitute a major proportion of the SRO diet. The uptake of the various food sources also varied considerably depending on local environmental conditions. Increases in SRO growth were strongly correlated to increases in temperature with a low temperature cut-off at ~13°C. Growth also appeared to reduce considerably when salinities lower than ~15ppt persisted for the order of a month. These factors may alter growth through changes in filtration rates. These processes were modelled in a coupled hydrodynamic-NPO (Nitrogen-Phytoplankton-Oyster) model of the Clyde River. This demonstrated that primary production was more affected by estuarine dynamics and nutrient concentrations than oyster uptake. At the current levels of oyster densities, primary production by itself could not account for the observed oyster growth, however growth became realistic with observed levels of POC added to the model. A set of environmental indices were used to complement the model and to assess the sustainability of the culture system. The combined indices indicated that while the ecological carrying capacity of the Clyde was exceeded the production capacity at an estuarine scale was not. On the lease scale, density experiments showed that while growth was not reduced as a result of current stocking densities, the condition index was significantly affected.

In free-stall systems cows are frequently moved among pens and regrouped. This practice involves individuals being mixed with unfamiliar cows, and stocking density often varies from before to after regrouping. Two separate lines of evidence suggest that regrouping and changing densities have negative impacts on cows welfare; but no study to date has assessed the combined effects. The aim of this study was to test the effect of changes in stocking density at the time of regrouping on the competition, feeding and lying behaviours and locomotor activity of dairy cows. By manipulating group size (6 vs. 12 cows) and pen size (12 vs. 24 stalls) three different stocking densities were created (25 %, 50 % and 100 %). Four groups of Holstein cows were regrouped weekly for 4 weeks and the stocking density changed from before to after each regrouping. The change in density varied from a decrease by a factor of 4 (100% to 25%), a decrease by a factor of 2 (100% to 50% or 50% to 25%), no change (50% to 50%), an increase by a factor of 2 (25% to 50% or 50% to 100%) and an increase by a factor of 4 (25% to 100%). Displacement at the feeding area, feeding time, lying time and the number of steps were scored. The daily means for each group were used to calculate the difference in responses from one day before to one day after each regrouping. Competition at the feed bunk changed after regrouping. The nature of the change was dependent upon the change in stocking density; when density decreased the number of displacements decreased. Changes in lying behavior and locomotor activity after regrouping also varied with changes in stocking density; when stocking density decreased lying time increased and number of steps increased. In conclusion, results of this experiment show that the change in competition behaviour from one day before to one day after regrouping varies with the change in stocking density at regrouping; and this change in competition results in changes in lying time and locomotor activity of cows.

Pasture-based livestock production is one of the major economic activities in Brazil. In general, the adoption of new forage materials by producers happens before enough information about their characteristics is generated, compromising their use in commercial systems. An experiment was conducted in Piracicaba, Brazil (22º42\' S, 47º30\' W, 580 m asl.), during two summer growing seasons, with the objective to describe and explain the tillering dynamics of the hybrid brachiariagrass Convert HD 364 (Brachiaria hybrid CIAT 36087) under continuous stocking and variable stocking rate. Responses studied were tiller population density (TPD), tillering demography (appearance rate-TAR - and survival rate- TSR), stability index (SI), average tiller weight (ATW), forage mass (FM), leaf area index (LAI), light interception (LI), mean leaf angle (MLA), stem apex height (hapex) and collar height of the youngest fully expanded leaf (hleaf). The experimental design was a randomized complete block with a factorial arrangement including all possible combinations between three sward heights (10, 25 and 40 cm) and growth rates (50 and 250 kg N ha-1 year-1), with three replications. The data were analyzed using the Mixed Models procedure of SAS and means compared using \"t\" test (P<=0.05). At 10 cm canopy height, Convert HD 364 had TPD 10 and 25% greater than at 25 and 40 cm, respectively. High growth rate resulted in 10% greater TPD and 9% lesser AWT. The 40-cm canopy resulted in ATW 80 and 274% greater than those at 25 and 10 cm, respectively. Under low and high growth rate, respectively, FM of 40-cm canopies was 163 and 41% greater than those of 10- -cm swards. Both, hapex and hleaf, responded similarly to treatments and were greater in taller canopies. Except for the 25-cm canopies there was no difference between growth rates in these responses. At greater growth rate TAR was 29% greater, whereas TSR 13% lesser. TAR and TSR varied along the experimental period, suggesting that they are affected by environmental factors. At the lower growth rate, there was no variation in SI along the experimental period, whereas at the high growth rate SI in February was 20 and 35% greater than in January and March, respectively. The determination of meristem location is an important tool to adequate planning of management strategies in animal production system under grazing.
A pecuária baseada em pastagens é uma das principais atividades econômicas do Brasil. Geralmente, ocorre adoção de novos materiais forrageiros sem que haja informações suficientes sobre suas características produtivas o que compromete seu potencial de uso. Um experimento foi conduzido em Piracicaba (22º42\' S, 47º30\' W, 580 m asl.) durante dois verões agrostológicos tendo por objetivo descrever e explicar a dinâmica de perfilhamento da Brachiaria híbrida Convert HD 364 (Brachiaria hybrid CIAT 36087) sob lotação contínua e taxa de lotação variável. Foram avaliados densidade populacional de perfilhos (DPP), demografia do perfilhamento (taxas de aparecimento - TAP- e sobrevivência de perfilhos - TSP), índice de estabilidade da população de perfilhos (IE), peso médio de perfilhos (PMP), massa de forragem (MF), índice de área foliar (IAF), interceptação luminosa (IL), ângulo de inserção da lâmina foliar (ALF), altura do meristema apical (AMA) e da lígula da última folha expandida (AFE). O delineamento experimental foi em blocos completos casualizados, com arranjo fatorial 3x2, correspondendo às combinações entre alturas de dossel (10, 25 e 40 cm) e taxas de crescimento (50 e 250 kg N ha-1 ano-1), com três repetições. Os dados foram analisados utilizando-se o procedimento de modelos mistos e as médias comparadas utilizando-se o teste \"t\" (P<=0,05). Sob altura de dossel de 10 cm, o capim Convert HD 364 apresentou DPP 10 e 25% superiores àquelas sob 25 e 40 cm, respectivamente. O aumento na taxa de crescimento resultou em aumento de 10% na DPP e decréscimo de 9% no PMP. O PMP foi 80 e 274% maior nos dosséis de 40 cm de altura do que nos de 25 e 10 cm, respectivamente. Dosséis mantidos a 40 cm submetidos à taxa de crescimento baixa e alta, respectivamente, apresentaram incremento de 163 e 233 % na MF do que dosséis de 10 cm. Obtiveram-se respostas similares entre AMA e AFE, nas quais houve um incremento na altura de ambas com o aumento da altura do dossel. Houve diferença entre as taxas de crescimento para AMA e AFE somente em dosséis de 25 cm. Com o aumento da dose de nitrogênio, TAP sofreu aumento de 29%, enquanto, TSP sofreu decréscimo de 13%. TAP e TSP variaram ao longo do período estudado, demonstrando a influência de fatores ambientais nas mesmas. Não houve variação no IE ao longo do período experimental em dosséis sob taxa de crescimento baixa, enquanto na taxa alta o IE foi 20 e 35% maior em Fevereiro do que em Janeiro e Março, respectivamente, para ambos os anos. A determinação da localização do meristema apical é uma importante ferramenta para o planejamento adequado de estratégias de manejo em sistemas de produção animal sob pastejo.

O estresse causa modificações no epitélio intestinal, tais como o aumento de células caliciformes e da taxa de apoptose. O uso de alimentos nutracêuticos tem sido uma alternativa para amenizar essas modificações sobre o tecido epitelial. Desta forma, este trabalho teve como objetivo avaliar se a inclusão de colostro bovino, o qual é constituído de fatores antioxidantes, imunes e de crescimento, seria capaz de amenizar as consequências do estresse crônico sob o intestino. Para isso, juvenis de pacu (Piaractus mesopotamicus) adensados a 50 kg/m3 foram alimentados duas vezes ao dia até a saciedade com ração peletizada e semi-purificada sem (0%CBL) e com a inclusão de colostro bovino liofilizado em concentrações crescentes (10, 20 e 30%CBL), (n=4). Após 28 dias, foram coletados segmentos do intestino médio, S1 e S2, e reto. Os tecidos foram marcados com corantes histológicos para a quantificação de células caliciformes contendo mucinas neutras, ácidas (incluindo sialo e sulfomucinas) e ácidas-neutras. Também foram mensurados o volume (Vv) e a densidade da superfície (Sv) da mucosa, por análise estereológica, e a espessura da camada muscular. A razão do número de cada tipo e subtipo de célula caliciforme sobre o Vv e Sv foi calculada para estimar a densidade de células caliciformes, Dv e Ds, respectivamente. A taxa apoptótica foi analisada qualitativamente através da intensidade (alta, média e baixa) da imunomarcação da caspase-3 nas células epiteliais. As dietas não influenciaram os parâmetros zootécnicos analisados (P>0,05). No reto, os grupos que receberam 20 e 30%CBL apresentaram menor número de células caliciformes contendo sulfomucinas e menor Ds em relação a 0 e 10% (P=0,0148 e 0,0198, respectivamente). No RT, Dv total e Dv de células caliciformes contendo mucinas ácidas foi maior em 0 e 30%CBL em relação a 20%CBL (P=0,0155 e 0,225, respectivamente). No S1, 10 e 30%CBL apresentaram maior Dv em relação a 20%CBL (P=0,0540). A espessura da camada muscular, o Vv e a Sv não diferiram entre os tratamentos (P>0,05). No S2 e RT, a taxa de apoptose teve relação inversa à concentração de colostro bovino liofilizado adicionado na ração. Nos três segmentos, houve maior proporção de células caliciformes contendo mucinas ácidas do que neutras, sendo a maioria representada por sulfomucinas. Assim, a inclusão de colostro bovino liofilizado nas rações de juvenis de pacu adensados diminuiu a apoptose nos segmentos intestinais S2 e RT e também diminuiu o número de células caliciformes contendo sulfomucinas no RT, indicando que o colostro bovino liofilizado pode ser utilizado como alimento nutracêutico para pacus (Piaractus mesopotamicus) adensados, a fim de diminuir a taxa apoptótica e proteger o intestino contra enzimas bacterianas, uma das principais funções das sulfomucinas.
The stress causes changes in the intestinal epithelium, such as the increase in the number of goblet cells and on the rate of apoptosis. The use of nutraceutical foods has been an alternative to soften these modifications on the epithelial tissue. Thus, this study aimed to evaluate if the inclusion of bovine colostrum, which is composed of antioxidant, immune and growth factors, would be able to attenuate the consequences of chronic stress on the intestine. For this, pacu juveniles (Piaractus mesopotamicus), stocked at density of 50 kg/m3, were fed twice daily until satiety with pelleted and semi-purified diet without (0% LBC) and with the inclusion of lyophilized bovine colostrum in increasing concentrations (10, 20 and 30% LBC), (n = 4). After 28 days, segments of the middle gut, S1 and S2, and rectum (RT) were collected. The tissues were stained with histological dyes for the quantification of goblet cells containing neutral, acidic (including sialo and sulphomucins) and acid-neutral mucins. The volume (Vv) and surface density (Sv) of the mucosa were also measured by stereological analysis and the thickness of the muscular layer. The ratio between the number of each goblet cell type and subtype and the Vv or Sv was calculated to estimate the density of goblet cells, Dv and Ds, respectively. The apoptotic rate was analyzed qualitatively according to the intensity (high, medium and low) of caspase-3 immunostaining in epithelial cells. The diets did not influence the zootechnical parameters analyzed (P> 0.05). In the rectum, the groups that received 20 and 30% LBC presented lower number of goblet cells containing sulphomucins and lower Ds in relation to 0 and 10% (P = 0.0148 and 0.0198, respectively). In RT, total Dv and Dv of goblet cells containing acid mucins were higher in 0 and 30% LBC in relation to 20% LBC (P = 0.0155 and 0.225, respectively). In S1, 10 and 30% LBC presented higher Dv in relation to 20% LBC (P = 0.0540). Muscle layer thickness, Vv and Sv did not differ between treatments (P> 0.05). In S2 and RT, the rate of apoptosis was inversely related to the concentration of lyophilized bovine colostrum added in the diet. In the three segments, there was higher proportion of goblet cells containing acidic than neutral mucins, most of them being sulphomucins. Thus, the inclusion of lyophilized bovine colostrum in diets of pacu juveniles reduced apoptosis in the intestinal segments S2 and RT and also decreased the number of goblet-containing sulphomucins in the RT, indicating that lyophilized bovine colostrum can be used as a nutraceutical feed for pacus (Piaractus mesopotamicus) under high stocking density to decrease the apoptotic rate and protect the intestine against bacterial enzymes, one of the main functions of sulphomucins.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
The feeding rates practiced in fish cultured directly influence the economic return of activity, because excessive rates result in zootechnical, economic losses and environmental. An alternative for improving the quality of crop water and increase the production of fish is the use of artificial substrates for colonization by periphyton. This study was conducted in two consecutive phases. The first phase of research was aimed at determining, in fish farming system based substrate, the optimal rate of feeding in each track of body weight, that maximizes the weight gain and feed efficiency, and minimizes the concentrations of ammonia and nitrite in pond water. Using seven treatments and a control, with five repetitions each, totaling 40 tanks of 250 L. In the treated groups growing feeding rates were evaluated, beginning with the following values: 3, 6, 9, 12%; 15, 18 and 21% biomass per day. The second phase of the study aimed to determine the best stocking density of juvenile tilapia fed at rates optimized in the cropping system based on substrate. By regression analysis of the results of final weight, specific growth rate and yield as a function of feeding rates employed, these variables observed increase in initial feed rate of about 12% of the biomass day -Â, occurring decreased these variables with increasing feed rate. Variables of water quality for initial feed rate of 12%, as NAT (0,39 mg/L), NH3 (0,026 mg/L) and O2D (5,18 mg/L) were within the acceptable for tilapia levels. With the increase in feed rate, there was worsening in water quality, it was not possible observe the effect of biofilter periphyton. Therefore in the first phase, that the optimal rate of feeding of juvenile Nile tilapia cultured in ponds with submerged substrates for periphyton, in the growing phase (1-30 g), corresponds to the initial rate of 12% biomass day-Â. In the second experimental phase, the rate of feeding and stocking density showed higher final body weight (25 g), yield (14,77 g/ mÂ/day) and TCE (5,16) were equal to 12% biomass day-Â (initial) and 9 fish/tank, respectively. The variables of water quality for this treatment were within the acceptable for growing tilapia tracks.
As taxas de arraÃoamento praticadas em cultivos de peixes influenciam diretamente no retorno econÃmico da atividade, pois taxas excessivas resultam em prejuÃzos zootÃcnicos, econÃmicos e ao meio ambiente. Uma alternativa para melhorar a qualidade da Ãgua de cultivo e aumentar a produÃÃo de pescado à o emprego de substratos artificiais para colonizaÃÃo por perifÃton. O presente trabalho foi realizado em duas fases consecutivas. A primeira fase teve como objetivo geral determinar, em sistema de cultivo de peixes baseado em substrato, a taxa de arraÃoamento Ãtima, em cada faixa de peso corporal, que maximiza o ganho em peso e a eficiÃncia alimentar; e minimiza as concentraÃÃes de amÃnia e nitrito na Ãgua de cultivo. Utilizando sete tratamentos e um controle, com cinco repetiÃÃes cada, totalizando 40 tanques de 250 L. Nos grupos tratados foram avaliadas taxas crescentes de arraÃoamento, iniciando-se com os seguintes valores: 3; 6; 9; 12%; 15, 18 e 21% da biomassa ao dia. A segunda fase do trabalho teve por objetivo determinar a melhor densidade de estocagem de juvenis de tilÃpia alimentados sob taxas otimizadas, em sistema de cultivo baseado em substrato. Pela anÃlise de regressÃo dos resultados de peso final, taxa de crescimento especÃfico e produtividade em funÃÃo das taxas de arraÃoamento empregadas, observou-se aumento dessas variÃveis atà a taxa de arraÃoamento inicial de, aproximadamente, 12% biomassa dia-Â, ocorrendo queda dessas variÃveis com a elevaÃÃo da taxa de alimentaÃÃo. As variÃveis de qualidade de Ãgua para taxa alimentar inicial de 12%, como NAT (0,39 mg/L), NH3 (0,026 mg/L) e O2D (5,18 mg/L) ficaram dentro dos nÃveis aceitÃveis para o cultivo de tilÃpia. Com o aumento da taxa de alimentaÃÃo, houve piora da qualidade de Ãgua, nÃo sendo possÃvel observar o efeito de biofiltro do perifÃton. Concluiu-se, na primeira fase, que a taxa Ãtima de arraÃoamento de juvenis de tilÃpia do Nilo cultivados em tanques com substratos submersos para perifÃton, na fase de recria (1 â 30 g), corresponde à taxa inicial de 12% biomassa dia-Â. Na segunda fase experimental, a taxa de arraÃoamento e a densidade de estocagem que proporcionaram maior peso corporal final (25 g), produtividade (14,77 g/mÂ/dia) e TCE (5,16) foram iguais a 12% da biomassa dia-1 (inicial) e 9 peixes/tanque, respectivamente. As variÃveis de qualidade de Ãgua para esse tratamento se apresentaram dentro das faixas aceitÃveis para o cultivo de tilÃpia do Nilo.

Made available in DSpace on 2016-08-17T18:39:44Z (GMT). No. of bitstreams: 1 4573.pdf: 2386349 bytes, checksum: 7ed71a71bbb8a21974731217325807a0 (MD5) Previous issue date: 2011-12-13
Financiadora de Estudos e Projetos
With the increased interest in growing native fish species the tetra has been highlighted nationally in the marketing of fish facing the two niche markets: as a snack in bars and restaurants and other natural bait for sport fishing. Therefore, studies on the stocking density are needed for better understanding in response to performance than can affect the growth, nutrition and animal behavior. This study aimed to evaluate the economic viability and growth performance of the tetra (Astyanax altiparanae) in cages, subjected to different stocking rates. The experiment was conducted on the premises of the UPD Pirassununga, APTA Pole Central East, in cages of 1m3, villages in densities: 250,450 and 600 fish per tank with 4 repetitions. The temperature, water clarity, dissolved oxygen an pH were daily measured. The tetra were fed extruded commercial diet containing 36%of protein. The experiment lasted 57 days and monthly samples were collected to evaluate the development and adjust amount of feed. To verify the significance between treatment means was used Tukey s test at 5% probability. The results showed increasing linear effect for variable total biomass (p<0,05) as opposed to the linear effect (p<0,05) for average consumption of feed as well as weight gain, average final length and final weight medium according to the increase of stocking density. The physic-chemical parameters remained at adequate levels. It is concluded that stocking density affects the development of juveniles of tetra and the density of persons over fishes/m³. Can still be used in the cultivation of 600 fishes/m³ tetra juveniles in cages, resulting in higher total biomass, although they result in smaller populations.
Com o aumento do interesse no cultivo de espécies de peixes nativos, o lambari tem se destacado nacionalmente na comercialização de pescado frente à dois nichos de mercado: um como petiscos em bares e restaurantes e outro como isca natural para a pesca esportiva. Sendo assim, estudos referentes à densidade de estocagem se fazem necessários para um melhor entendimento frente ao desempenho produtivo que pode afetar o crescimento, a alimentação e o comportamento dos animais. Neste estudo, objetivou-se avaliar a viabilidade econômica e o desempenho produtivo do lambari (Astianax altiparanae) em tanquesrede, submetidos à diferentes densidades de estocagem. O experimento foi conduzido nas instalações da UPD de Pirassununga, Pólo APTA Centro-Leste, em tanques-redes de 1m3, povoados nas densidades de: 250, 400 e 600 peixes por tanque com 4 repetições. A temperatura, transparência da água, oxigênio dissolvido e o pH foram aferidos diariamente.Os lambaris foram alimentados com ração comercial extrusada contendo 36% de proteína bruta. O experimento durou 57 dias e mensalmente foram realizadas biometrias para avaliar o desenvolvimento e o ajuste da quantidade de ração. Para verificar a significância entre as médias dos tratamentos foi utilizado o teste de Tukey, ao nível de 5% de probabilidade. Os resultados mostraram efeito linear crescente para variável de biomassa total (p<0,05) em oposição ao efeito linear decrescente (p<0,05) para consumo médio de ração, assim como ganho de peso médio, comprimento final médio e peso final médio conforme aumento da densidade de estocagem. Os parâmetros físicoquímicos permaneceram em níveis adequados. Conclui-se que a densidade de estocagem afeta o desenvolvimento dos juvenis de lambari e que a densidade de 300 peixes/m3proporciona indivíduos maiores. Ainda pode-se utilizar 600 peixes/m3 no cultivo de juvenis de lambari em tanque-rede, resultando em maior biomassa total, apesar de resultarem em populações menores.

O objetivo deste estudo foi avaliar o efeito da densidade sobre o desempenho e o comportamento de leitões na fase de creche. Um total de 560 leitões desmamados (peso médio de 5,75 ± 0,9 kg e idade média de 20,92 ± 0,8 dias) foram aleatoriamente alojados em quatro tratamentos com diferentes densidades: T0,33, T0,28, T0,23 e T0,18 (0,33, 0,28, 0,23 e 0,18 m²/animal respectivamente). As baias continham 20 animais e a ração foi fornecida à vontade. As lesões de cauda e orelha foram graduadas em escores de 0 a 4 e o número de lesões de briga foram avaliados semanalmente. Dezesseis baias foram filmadas em três momentos (1ª, 4ª e 6ª semana de alojamento) para avaliação da frequência de brigas e de belly nosing. Foi observado um efeito linear da densidade sobre o ganho de peso diário (GPD; P=0,049), um efeito quadrático sobre o peso aos 42 dias (P=0,030) e uma tendência de efeito quadrático para o consumo médio diário (CMD; P=0,075). Não houve efeito da densidade na conversão alimentar (CA) e no coeficiente de variação (CV) do peso aos 42 dias. Foi observado um maior número de leitões apresentando lesões severas de orelha no grupo T0,18 quando comparado ao T0,33 (P = 0,019) e T0,28 (P = 0,056). Um maior número de animais com lesões moderadas ou severas foi observado no grupo T0,18 (P < 0,05) do que nos demais grupos para lesões de orelha, e do que T0,33 para lesões de cauda. Houve um efeito linear da densidade sobre a frequência de brigas, com uma maior ocorrência nos grupos com menos espaço. Contudo, não foi observado efeito sobre o número de lesões de briga ou de casos de belly nosing. Em conclusão, o aumento da densidade afetou negativamente o desempenho dos leitões, além de aumentar a ocorrência de comportamentos indesejáveis.
The aim of this study was to evaluate the effect of space allowance on performance and behavior of nursery pigs. At weaning 560 pigs (5.75 ± 0.9 kg of body weight and 20.92 ± 0.8 days of age) were randomly assigned in four treatments with different stocking densities: T0.33, T0.28, T0.23 and T0.18 (0.33, 0.28, 0.23 and 0.18 m²/pig respectively). Pens were standardized to have the same group size (20 pigs/pen) and feed was provided ad libitum. Tail and ear biting lesions and the fighting lesions were weekly observed. Sixteen pens were videotaped in three different moments (1st, 4th and 6th housing week) and the frequency of fights and belly nosing were recorded. A linear effect was observed of stocking density on average daily gain (ADG; P=0.049), a quadratic effect and a quadratic tendency of effect were observed on body weight at 42 days after weaning and on average daily feed intake (ADFI) (P=0.030; P=0.075, respectively). There was no effect of stocking density on the gain:feed ratio or weight coefficient of variation (CV) at day 42. Higher graduation of severe ear lesions was observed in pigs from T0.18 when compared to T0.33 (P = 0.0196) and T0.28 (P = 0.056). A higher number of pigs with moderate or severe tail and ear lesions was observed in T0.18 (P > 0.05). Moreover, it was observed a linear effect of density on the frequency of fights, with higher occurrence in groups housed in restricted spaces. However, no effect of stocking density was observed on fight lesions or belly nosing among treatments. In conclusion, increased density negatively affected the performance of piglets and increased the occurrence of unsuitable behaviors.

Dairy farmers in the Northeastern Unites States are paid based on the amount of fat and protein in their cows' milk, and improving fat and protein production is linked with improved financial sustainability for dairy farms. However, not all farmers are motivated to make changes to increase milk fat and protein production. Previous research has identified a positive correlation between a group of fatty acids, known as the de novo fatty acids, and the fat and protein content of bulk tank milk from commercial dairy farms. Therefore, the first objective of this research was to explore the relationship of farm management, the cow's diet, and lactation performance with de novo fatty acid content on Northeastern US dairy farms. Results from the first objective were communicated with dairy farmers; therefore, the second objective was to understand how to communicate with farmers to influence their behavior. We hypothesized that farms with high de novo fatty acids in bulk tank milk would manage and feed their cows to optimize rumen fermentation conditions. The first (Chapter 2) and second (Chapter 3) studies were methodologically very similar. Farms were categorized as either high de novo (HDN) or low de novo (LDN) based on the concentration of de novo fatty acids in their bulk tank milk for the 6 months prior to the farm visit. Farms were then visited once in March or April, 2014 (Chapter 2) or between February and April, 2015 (Chapter 3) to assess management practices and collect samples of the cows' diet. There were no differences in days in milk in Chapter 2 or Chapter 3. Yield of milk, fat, and true protein per cow were higher for HDN versus LDN farms in Chapter 2. In both chapters, HDN farms had higher milk fat and true protein content and higher de novo fatty acid yield per day. The HDN farms had lower freestall stocking density in Chapter 2 and provided more feedbunk space per cow in Chapter 3. Additionally, tiestall feeding frequency was higher for HDN than LDN farms. No differences were detected for dietary chemical composition, except ether extract was lower for HDN than LDN farms in both chapters. Chapter 4 explored how to communicate the results of Chapter 2 and Chapter 3 through eleven qualitative, semi-structured interviews and insight from the 83 farm visits. Farmers identified the cooperative, expert consultants (nutritionist, veterinarian, and agronomists), financial advisers, print publications, and other farmers as principal sources of information. However, barriers to the transfer of information included family dynamics, lack of access to high speed internet, and difficulties evaluating divergent recommendations from experts. Several farmers expressed an incorrect perception of their farms' fat and protein production compared with cooperative averages which reduced their motivation to incorporate management changes. Recommendations to overcome these barriers include integrating management team meetings and facilitating informal discussion groups between farmers. This research is correlational in nature, and future research is needed to verify a causal relationship between de novo fatty acids and milk fat and protein content. However, the results of this research can be used to help farmers increase their cows' milk fat and protein content, improve the transfer of knowledge to dairy farmers, and ultimately support the financial sustainability of dairy farms in the Northeastern US.

Made available in DSpace on 2014-12-17T15:37:19Z (GMT). No. of bitstreams: 1 EricSF.pdf: 350001 bytes, checksum: 9fc8363dd4359a5ba205b8e441f4895c (MD5) Previous issue date: 2006-06-28
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Carciniculture in Brazil occupies world-wide prominence due to shrimp culture, and the state of Rio Grande do Norte has presented the best results in the culture of the Litopenaeus vannamei in the last decade. This species has been shown to adapt easily to different environments and is between the five most cultivated penaeids of the world. The ponds are usually constructed in areas close to water courses and estuaries. Stock density and substrate ponds can pollute environment, causing losses in the growth and survival of the shrimps, being considered stress factors. Shrimps in inadequate densities and substrates can result reduced productivity of the farm; and favor diseases. So, it is important to verify how these variables influence the development of the animals in the culture farms. Our objective was to study the influence of the type of substrate and the stock density on the behavior and haemocyte count of the L. vannamei. Individually marked juvenile shrimps were kept in aquaria with 30 L of seawater and continuous aeration, in 12L-12D photoperiod. They were observed through Ad libitum and focal sampling instantaneous methods during thirty days, five times per week, six times per day (8:00 to 18:00) in windows of 15 minutes every two hours. The marking of carapace permitted quantifying molting and the feeding was supplied three times a day. Two experiments were carried out: the first one tested animals in the three different substrates (fine sand, smaller rocks-SPP and biggest rocks-SGR) with 33 shrimp/m2. In the second one, the animals were tested in three stock densities (26, 52 and 66 shrimp/m2) in fine sand substrate. At the end of experiment, biometry (first and second ones) and haemocyte count (second one) were made. The behavior of the L. vannamei seems to have been influenced by substrate and stocking density. In low granulometry of the substrate; the exploratory behavior became more frequent and inactivity of the shrimps was reduced. Burrowing was registered in sand substrate, specially in the initial period of the day. Cleaning was gradually higher along the day, presenting the biggest levels as the dark phase approached. The ingestion of feeding was more frequent in low density, and the animals were bigger and heavier at the end of the experiment. In the fine sand condition, the animals presented better growth, probably associated with the burrowing. The molting was equivalent in all types of substrate, but it was more frequent in high densities. Mortality of the shrimps was more frequent in high densities, and cannibalism and diseases were also registered in that condition. The clinical signals were similar to the ones of infectious mionecrosis (IMNV), generally associated with environment and physical stress. The haemocyte count was low for the hematologic standards of the penaeid, which we attributed for greater dilution of haemolymph in the postmolting phase. Smaller shrimps presented lower levels of haemocytes in relation to the bigger animals, count was also low in 26 shrimp/m2 density. The study demonstrates that stocking density and the granulometry of the substrate can affect the welfare, the health and the behavior of the L. vannamei. The sand substrate and low stocking density can be important tools in the management systems of shrimp production
A carcinicultura brasileira ocupa lugar de destaque mundial devido ? cria??o de camar?o, sendo o Rio Grande do Norte o maior produtor no cultivo de Litopenaeus vannamei. Essa esp?cie apresenta grande adapta??o ambiental e est? entre os cinco pene?deos mais cultivados do mundo. A cria??o ? realizada em viveiros nas ?reas pr?ximas a cursos d ?gua e estu?rios. Altas densidades populacionais e o substrato dos viveiros acarretam o aumento da polui??o e promovem perdas no crescimento e na sobreviv?ncia dos camar?es, sendo considerados fatores estressantes. Esses fatores podem comprometer a produtividade dos viveiros e favorecer doen?as, sendo importante verificar como essas vari?veis influenciam no desenvolvimento dos animais nas fazendas de cultivo. Nosso objetivo foi estudar a influ?ncia do tipo de substrato e da densidade populacional sobre o padr?o de atividades comportamentais e os n?veis de hem?citos (CHT) de L. vannamei. Em aqu?rios com 30 litros de ?gua salgada com aera??o cont?nua e em fotoper?odo 12C 12E (claro das 06:00 ?s 18:00), camar?es juvenis marcados individualmente foram observados pelos m?todos Ad libitum e focal instant?neo durante 30 dias, 5 vezes por semana, 6 observa??es di?rias (iniciando a primeira ?s 8:00 e a ?ltima ?s 18:00) em janelas de 15 minutos a cada duas horas, sendo registrado a cada minuto os seus comportamentos e localiza??o. Tamb?m foi feita a marca??o da carapa?a para quantificar as ecdises e a alimenta??o foi fornecida tr?s vezes ao dia. Dois experimentos foram realizados: tr?s substratos diferenciados (Areia, Seixos Pequenos e Seixos Grandes) com 33 animais/m2; e outro com tr?s densidades populacionais (26, 52 e 66 animais/m2) em substrato arenoso. Ao final dos experimentos, foram feitas a biometria dos camar?es e a contagem de hem?citos (apenas no 2? experimento). O padr?o geral de atividades comportamentais de L. vannamei n?o foi influenciado pelo substrato e densidade populacional. Contudo, ? medida que diminuiu a granulometria do substrato, o comportamento de explora??o tornou-se mais freq?ente e reduziu a inatividade dos camar?es. O enterramento foi registrado em substrato arenoso, sendo maior no per?odo inicial do dia. A limpeza distribuiu-se de forma crescente ? medida que a fase escura se aproximava, sendo maior ? noite. A ingest?o alimentar foi mais freq?ente em densidade baixa; acarretando maior crescimento nos camar?es. Houve maior ganho de peso nos animais em substrato arenoso, podendo estar associado com o enterramento e a taxa de crescimento dos animais. A taxa de ecdise foi igual em todos os substratos testados, mas a taxa de ecdise foi maior em maiores densidades. A mortalidade foi mais elevada em condi??es de maiores densidades, sendo registrados canibalismo e enfermidades nos animais. Os sinais cl?nicos foram semelhantes aos da mionecrose infecciosa (IMNV), geralmente associada ao estresse ambiental. Os n?veis de hem?citos foram baixos para os padr?es dos pene?deos, atribu?da pela maior dilui??o da hemolinfa na fase de p?s-ecdise. Camar?es menores apresentaram n?meros de hem?citos reduzidos em rela??o aos maiores, sendo tamb?m baixos em densidade de 26 camar?es/m2. O estudo demonstrou que os efeitos da densidade populacional elevada e a gramulometria do substrato podem afetar o bem estar, a sa?de e o comportamento de L. vannamei. O uso de substrato arenoso e baixa densidade populacional parecem ser medidas de manejo importantes em um sistema de produ??o de camar?o

Les salmonidés sont des poissons territoriaux en rivière, soumis à une compétition intense pour l'habitat et la ressource trophique dès les plus jeunes stades. Ces interactions exercent une influence sur la mortalité, la migration et la croissance, avec des intensités variables en fonction de l'ontogénie et des facteurs environnementaux. En Suisse, la truite Salmo trutta L. est l'espèce la plus prisée par les pêcheurs amateurs. La majeure partie des populations fait l'objet de rempoissonnements à partir de juvéniles " estivaux " relâchés au cours de leur premier été. L'élevage en pisciculture peut avoir des effets néfastes sur la diversité génétique et la fitness des poissons introduits dans le milieu naturel. En outre, ces individus sont susceptibles d'affecter la dynamique des populations sauvages. Certains comportements (agressivité, comportement anti-prédateur) ont été étudiés en milieu contrôlé, mais les conséquences ont rarement été mesurées en milieu naturel. Ce travail de thèse vise à évaluer l'intensité des mécanismes biotiques ou densité-dépendants entre des truites sauvages et introduites sur la base d'expérimentations en rivière. Les interactions biotiques ont d'abord été décrites au stade juvénile dans une population naturelle résidente. Puis, des expérimentations ont été menées en milieu contrôlé et in situ pour évaluer l'efficacité et les limites de deux méthodes de marquages utilisables sur des jeunes stades de truites : un marquage fluorescent à détection externe utilisant la calcéine et un marquage individuel par implantation de PIT tag. Ces techniques ont été employées pour évaluer les effets de la densité et de la taille des poissons introduits sur les juvéniles sauvages, à partir d'investigations conduites in situ dans trois rivières contrastées. Enfin, les résultats des différentes expériences de marquage-recaptures ont été utilisés pour modéliser la mortalité apparente des poissons introduits comparativement aux poissons sauvages, et rechercher les facteurs environnementaux susceptibles d'expliquer la variabilité observée. Les résultats montrent l'importance de la régulation densité-dépendante sur la survie apparente (ou taux de changement) et sur la taille des poissons sauvages, ainsi que les interactions entre la densité et les facteurs environnementaux, en particulier le débit. Dans les cours d'eau soumis à repeuplement, la survie des poissons sauvages est généralement bien supérieure à celle des poissons introduits, excepté dans le cours d'eau à faible pente. L'augmentation de la densité introduite n'influence pas directement la survie des poissons introduits ni celle des poissons sauvages, mais peut augmenter la dévalaison des individus des deux origines. En agglomérant les données de marquage-recaptures collectées dans sept rivières, les résultats indiquent une augmentation de la mortalité apparente initiale (dans les premiers jours suivant l'alevinage) des juvéniles introduits en fonction de la densité repeuplée et de la largeur du cours d'eau. Les caractéristiques morphologiques des cours d'eau influencent également la surmortalité apparente des poissons introduits sur le long terme. Ces résultats doivent être confirmés sur la base d'expérimentations de marquage-recaptures couplés à des relevés environnementaux détaillés.

Orientadora: Ana Cláudia Ruggieri
Banca: André Fischer Sbrissia
Banca: Kleber Tomás de Resende
Resumo: A produção de forragem é influenciada pelas estratégias de manejo impostas a ela, desta maneira, as técnicas para identificação do melhor momento para início e término do pastejo, aliadas aos estudos das características morfogênicas e estruturais das plantas, tornam-se úteis para direcionamento do manejo, pois buscam auxiliar no melhor entendimento do crescimento vegetal, e por conseqüência, da produção forrageira. O experimento foi realizado no setor de Forragicultura, em área pertencente à FCAV da UNESP - Jaboticabal no período de dezembro de 2008 a abril de 2009, com o objetivo de avaliar o efeito de índices de área foliar residual (IAFr) sobre as características morfogênicas e estruturais, além do acúmulo de forragem em pastos de Cynodon spp cv Tifton-85 sob regime de lotação rotacionada com ovinos. Os tratamentos foram constituídos por três IAFr, 2,4, 1,6 e 0,8, mantidos por regime de lotação rotacionada com ovinos. O delineamento experimental utilizado foi o de blocos completos casualizados em arranjo de parcelas subdivididas no tempo com sete repetições, totalizando 21 unidades experimentais. Foram avaliadas nas condições de pré e pós-pastejo, as alturas do dossel, os IAF e a massa de forragem, além da taxa de acúmulo de forragem e as características morfogênicas e estruturais dos pastos. No pré e pós-pastejo as alturas médias e o IAF do dossel se comportaram de forma análoga, decrescendo com a diminuição dos IAFr. O maior valor de interceptação luminosa no pós-pastejo (68,19%), foi verificado para o IAFr 2,4 e o menor valor (35,57%) para o IAFr 0,8. A taxa de aparecimento de folhas foi maior para o dossel mantido sob IAFr 0,8 em função da sua menor taxa de alongamento de colmos (0,51 cm/perfilho.dia). Os pastos mantidos sob IAFr 0,8 apresentaram maior densidade populacional de perfilhos. A massa de forragem seca... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The production of forage is influenced by handling strategies imposed on the techniques to identify the best moment for the beginning and ending of grazing, linked to the studies of morphogenetic and structural characteristics of plants, become useful tools for the directing of management for they aim to aid the best understanding of vegetal growth, and as consequence, forage plants. The experiment was conducted at Setor de Forragicultura at Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, at UNESP - Jaboticabal from December 2008 to April 2009, and aimed to evaluate the effect of residual leaf area index (LAIr) about the morphogenical and structural characteristics, and forage accumulation in pastures of Cynodon spp cv Tifton-85 in a rotational stocking system with sheep. The treatments were constituted by three LAIr, 2,4, 1,6 e 0,8, maintained by rotational stocking with sheep. A complete randomized block design was used arranged in sub-divided parcels with seven replications, totaling 21 experimental units. They were evaluated in pre and post-grazing conditions, the height of the sward, LAI and forage mass, besides the accumulation of forage rate and the morphogenetic and structural characteristics. In the pre and post-grazing, the average height and the LAI of sward, decreasing with the diminishing of LAIr. The biggest value of light interception in post-grazing (68,19%), was verified by LAIr 2,4 and the smallest value (35,57%) for LAIr 0,8. The stem elongation rate (0,51 cm/tiller.day). The grazing maintained by LAIr 0,8 had higher tiller population density. The total dry forage mass was 27,1% superior for LAIr 2,4 regarding to LAIr 0,8 in pre-grazing conditions, being this total production, 72,0% was composed by stem fractions and dead material. The biggest rates of dry matter accumulation were observed with LAIr 2.4, in the second and third grazing cycles... (Complete abstract click electronic access below)
Mestre

Made available in DSpace on 2017-07-10T17:48:19Z (GMT). No. of bitstreams: 1 Evandro_Kleber_Lorenz.pdf: 2851299 bytes, checksum: e8177ab9b556d239d3038a5b4241bdca (MD5) Previous issue date: 2010-02-23
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The density of stocking (DS) is a factor that can affect the development of fish. The aim of this current study was to analyze the effect of DS over the survival, weight, growth, and biomass hematology and chemical composition of juveniles Brycon orbignyannus farmed in cages. The experiment was realized in the area of transition of the tank of Itaipu Binational in the center of research development to fish farm in cages located in the Biological Refuge in the city of Santa Helena-PR, for a period of five months. It was used 750 juveniles with an initial average weight and length of 26.72+-5,99 g and 13.45+-0,99cm, respectively distributed in twelve cages of 1,00m3 randomly in a design completely casualized and three repetitions. The animals received commercial food extruded containing 36% of rough protein and they were feed three times a day until the visible satiety. At the end of the experimental period, the fish were kept in fasting for a period of 24 hours. Subsequently, they were realized the proceeding of blood collection assessment of the parameters of performance, income and chemical composition of the animals carcass. The survival and the final biomass increased straightly with the increase number of animals stocked for unit productive. The values of income of carcass as gutted weight, clean barrel, fillet, head and grease visceral didn t present significant difference (p>0.05) between the treatment. However, the total length and pattern, gain weight, total weight and hipathossomatic indices presented significant difference (p<0.05) and effect quadratic of the treatment. The chemical analyzes of the animals carcass didn t differ, statistically (p>0.05) to the variable dry material, protein and mineral material, so that, the higher lipic deposition was watched at fish produced in density 50 fish per m3. The varieties erythrocitics as hemoglobin and hematocrito didn t present difference statistics (p>0.05) to the treatment used, however, the total erythrocitics and the glucose differed significantly (p<0.01 and p<0.05, respectively) between the densities. It was concluded that the best density to the farm of piracanjuba in cages is between 58and 75 fish per m3
A densidade de estocagem (DE) é um fator que pode afetar o desenvolvimento dos peixes. O objetivo do trabalho foi avaliar a densidade de estocagem de juvenis de Brycon orbignyanus cultivados em tanques-rede sobre a sobrevivência, peso, crescimento, biomassa, hematologia e composição química. O experimento foi realizado durante cinco meses na área de transição do reservatório da Itaipu Binacional no Centro de Desenvolvimento de Pesquisa para Piscicultura em Tanques-rede localizado no Refúgio Biológico do município de Santa Helena PR. Foram utilizados 750 juvenis com peso e comprimento médio inicial de 26,72±5,99g e 13,45±0,99cm, respectivamente, distribuídos em 12 tanques-rede de 1,00 m3 em um delineamento inteiramente casualizado. Foram utilizados quatro tratamentos (25, 50, 75 e 100 peixes/m3) e três repetições. Os animais receberam ração comercial extrusada contendo 36% de proteína bruta e foram alimentados três vezes ao dia até a saciedade aparente. Ao final do período experimental, os peixes permaneceram em jejum por um período de 24 horas para, posteriormente, serem realizados os procedimentos de coletas de sangue e avaliações dos parâmetros de desempenho, rendimento e composição química da carcaça dos animais. A sobrevivência e a biomassa final aumentaram linearmente com o aumento do número de animais estocados por unidade produtiva. Os valores de rendimento de carcaça como peso eviscerado, tronco limpo, filé, cabeça e gordura visceral não apresentaram diferenças significativas (p>0,05), entre os tratamentos. Entretanto, o comprimento total e padrão, ganho de peso, peso total e índice hepatossomático apresentaram diferenças significativas (p<0,05) e efeito quadrático para os tratamentos. A análise química da carcaça não diferiu estatísticamente (P>0,05) para as variáveis matéria seca, proteína e matéria mineral, no entanto, a maior deposição lipídica foi observada nos peixes produzidos na densidade de 50 peixes/m3. As variáveis eritrocitárias como hemoglobina e hematócrito não apresentaram diferenças estatísticas (P>0,05) para os tratamentos utilizados, porém, o eritrócito total e a glicose diferiram significativamente (P<0,01 e P<0,05, respectivamente) entre as densidades. Concluiu-se que a densidade ótima para o cultivo de piracanjuba em tanques-rede fica entre 58 e 75 peixes/m3

Cilj istraţivanja bio je da se ispita uticaj svetlosnog programa (konstantnog – KS i opadajuĆe- rastuĆeg - ORS), gustine obroka i gustine naseljenosti i njihove interakcije na proizvodne i klaniČne osobine brojlerskih piliĆa, kvalitet mesa i ošteĆenje tabanskih jastuČiĆa.Istraţivanja su sprovedena na farmi piliĆa Donji Crnci nadomak Podgorice u tri ogleda: u prvom su ispitivani efekti svetlosnog programa i gustine obroka, u drugom programi svetla i gustina naseljenosti piliĆa, a u treĆem program svetla i gustina obroka (smeše sa standardnim i poveĆanim sadrţajem energije i proteina, pri Čemu je odnos energija : protein bio konstantan). U svakom ogledu bilo je 320 piliĆa linijskog hibrida Cobb 500, mešanih po polu, a ogledi su trajali 42 dana. U sva tri ogleda formirane su po Četiri grupe sa Četiri ponavljanja i u svakoj grupi bilo je 80 jednodnevnih piliĆa.Proizvodni parametri (telesna masa, utrošak hrane i uginuĆa) praĆeni su u svim ogledima, a izraČunati su konverzija hrane i proizvodni indeks. Telesne mase su merene u uzrastu od 1; 7; 14; 21; 28; 35 i 42 dana. Utrošak hrane utvrčivan je na kraju perioda primene pojedinih smeša, i to: 14. dana koliČina konzumirane starter smeše, 35. dana grovera i 42. dana finišer smeše. Mortalitet je odrečivan beleţenjem broja uginulih piliĆa u toku trajanja ogleda. Na osnovu telesnih masa, konverzije hrane i mortaliteta izraČunati su proizvodni indeksi.Na kraju svakog ogleda, sa 6 nedelja starosti, piliĆi su izmereni pojedinaČno, izraČunati su proseci tretmana, a zatim je od svakog tretmana izdvojeno 20 piliĆa (10 muških i 10 ţenskih) radi ispitivanja klaniČnih karakteristika. Pre klanja piliĆi su gladovali 12 sati. Nakon klanja i ČišĆenja trupovi su ohlačeni na 40C u toku 24 sata, a potom obračeni kao: „klasiČna obrada” „spremno za peČenje” i „spremno za roštilj”.Pri konfekcioniranju trupova izdvojena je abdominalna mast, izmerene mase obračenih trupova i dobijeni randmani. Radi utvrčivanja prinosa i udela osnovnih i sporednih delova trupa izvršeno je rasecanje ohlačenih trupova. Ocena konformacije trupova izvršena je na osnovu utvrčenih apsolutnih mera: duţine piska, duţina kobilice, dubina grudi i obim bataka. KorišĆen je indeks koji predstavlja odnos ţive mase pre klanja i posmatrane mere (g/mm).U ogledu II izvršeno je i fiziČko ispitivanje kostiju, na femuru nakon izdvajanja od skeleta brojlera, a u ogledu III odrečeni su sadrţaj vlage, sadrţaj ukupne masti, ukupnog pepela i ukupnih proteina belog i crvenog mesa, na uzorcima mišiĆnog tkiva grudi i karabataka od 5 muških i 5 ţenskih trupova u svakom tretmanu (ukupno 20).  Rezultati ukazuju da svetlosni program nije statistiČki znaČajno uticao na završne telesne mase u ogledima I i II, dok su u ogledu III veĆe mase utvrčene kod piliĆa tovljenih pri KS. Primena ORS uticala je na usporavanje stope rasta u prvom periodu tova, a kao rezultat kompenzacionog porasta bez uticaja na završne mase, sem u treĆem ogledu. Bolju konverziju hrane u periodu ishrane finišerom postigli su piliĆi u ogledu I pri ORS nego pri KS, kao i u ishrani starterom u ogledu III. Svetlosni programi u ogledu II nisu uticali na konverziju hrane i mortalitet piliĆa.Gustina obroka nije uticala na završne mase, konverziju hrane, mortalitet i proizvodni indeks. Kod piliĆa hranjenih obrocima sa višim sadrţajem proteina i energije utvrčene su veĆe telesne mase na kraju tova (P<0.01). Gustina obroka u ogledima I i III nije imala uticaj na konverziju hrane, mortalitet i proizvodni indeks. Znatno je veĆa završna masa piliĆa tovljenih pri gustini naseljenosti od 12 grla/m2 (2667,08 g) nego pri 17 grla/m2 (2435,76 g) i razlike su bile statistiČki visoko znaČajne. Nije utvrčen uticaj gustine naseljenosti na konverziju hrane, mortalitet i proizvodni indeks.Ispitivani faktori (svetlo, gustina obroka i gustina naseljenosti) nisu uticali na randmane, ali jesu interakcije nekih od njih. U svim ogledima utvrčen je manji udeo abdominalne masti pri ORS nego pri KS, ali bez statistiČke znaČajnosti. Gustina obroka i gustina naseljenosti nisu uticali na sadrţaj abdominalne masti. VeĆi je sadrţaj abdominalne masti u svim ogledima bio kod ţenskih nego muških piliĆa. Udeo grudi veĆi je pri KS nego pri ORS, ali su razlike statistiČki znaČajne samo u treĆem ogledu. Gustina obroka i gustina naseljenosti nisu uticale na udeo grudi. Udeo bataka bio je veĆi kod piliĆa tovljenih pri ORS nego pri KS, ali su razlike statistiČki znaČajne samo u prvom ogledu. Udeo karabataka u prvom i drugom ogledu nije se znaČajno razlikovao izmeču svetlosnih programa, dok je u treĆem bio veĆi pri ORS nego pri KS (P<0.01). Nije utvrčen uticaj gustine naseljenosti i gustine obroka na udeo bataka i karabataka. Kod muških piliĆa utvrčen je veĆi udeo bataka, a kod ţenskih karabataka.Relativne vrednosti mera konformacije nisu bile pod uticajem svetlosnih programa i gustine obroka, osim što je pri manjoj gustini naseljenosti relativna vrednost dubine grudi bila veĆa (P<0.05). Na ošteĆenje tabanskih jastuČiĆa nije utvrčen uticaj svetla i gustine obroka, ali su piliĆi pri veĆim gustinama naseljenosti, poČev od 28. dana, imali znatno veĆa ošteĆenja tabanskih jastuČiĆa nego pri manjoj gustini.Svetlosni program i gustina naseljenosti nisu uticali na fiziČke osobine femura: površinu preseka, silu loma i specifiČnu silu loma. Muški piliĆi imali su veĆi površinu preseka i silu loma femura, razlike za površinu preseka su statistiČki znaČajne, ali ne i za silu loma.Procenat masti u tamnom mesu bio je veĆi, a proteina niţi pri ORS nego pri KS. Ostali parametri hemijske analize tamnog i belog mesa nisu bili pod uticajem svetlosnih programa. Gustina obroka nije imala uticaj na hemijski sastav mesa grudi i karabataka.Na osnovu svega iznesenog moţe se zakljuČiti da su sva tri faktora (svetlosni program, gustina obroka i gustina naseljenosti), kao i njihove interakcije, uticali na brojne proizvodne parametre i kvalitet mesa brojlera, pa i na njihovu dobrobit u razliČitim fazama tova. ImajuĆi u vidu ogromne razlike u efektima koji se mogu postiĆi pri razliČitim kombinacijama ovih Činilaca, rezultati ovih i sliČnih istraţivanja treba da olakšaju izbor tehnologije koja Će davati najbolje ekonomske efekte u tovu piliĆa. Takoče, tamo gde su rezultati nejasni ili kontradiktorni, treba nastaviti istraţivanja na veĆem broju jedinki i fokusirati se na ekonomski vaţnije proizvodne i klaniČne osobine piliĆa.
The purpose of the research was to investigate the effect of the lighting program (constant – KS and intermittent – ORS), feed density and stocking density and their interaction with production and slaughterhouse characteristics of broiler chicken, meat quality and feet pad damage.The research was conducted on a chicken farm Donji Crnci in the vicinity of Podgorica, in three trials: the first trial focused on effects of the lighting program and feed density, the second on the lighting program and stocking density and the third on the lighting program and the feed density (mixes with standard and increased content of energy and protein, with a constant energy:protein ratio). Each of the trials included 320 chicken of the Cobb 500 hybrid line, mixed sexes; trials lasted for 42 days. In all three trials, four groups were formed with four repetitions and each group included 80 one-day chickens.Production parameters (weight, feed consumption and deaths) were monitored in all trials and feed conversion ratio and production index were calculated. Weight was measured when broilers were 1; 7; 14; 21; 28; 35 and 42 days old. Feed consumption was determined at the end of the use of specific mixes, as follows: 14th day the quantity of starter mix consumed, 35th day the quantity of grower mix consumed and 42nd day quantity of the finisher mix. Mortality rate was determined by recording the number of chicken that died during the trial. Production indices were calculated based on weight, food conversion ratio and mortality.At the end of all trials, at 6 weeks of age, the chickens were measured individually, group averages were calculated and then by random sampling, 20 chicken were taken from each group (10 males and 10 females) in order to analyse slaughter characteristics. Pre-slaughter fasting lasted for 12 hours. After slaughter and cleaning, the carcasses were cooled to 40C over 24 hours and then processed as: “classical processing”, “ready to grill” and “barbecue ready”.In carcass processing, abdominal fat was taken out, weight of processed carcases measured and carcass yield values were obtained. In order to determine the yield and share of the main and secondary parts of the carcass, cooled carcasses were cut out. Evaluation of carcass conformation was done on the basis of absolute measures of the following: metatarsus length, keel length, breast depth and drumsticks circumference. Index representing the ratio of live weight before slaughter and measure observed was used (g/mm).In Trial II, physical examination of bones was done, on femur, upon separation from the broiler skeleton, and in Trial III moisture content, total fat content, total ash content and total protein of white and red meat was determined on samples of muscle tissue of breasts and thighs of 5 male and 5 female carcasses in each of the treatments (20 in total).The results show that lighting program had no statistically significant effect on final body weight in Trials I and II, while in Trial III, higher weights were recorded in chicken fattened under KS. ORS resulted in slowing down of the growth rate in the first fattening period, and as a result of compensatory growth it had no effect on final weights, except in the third trial. Better food conversion ratio in the period of finisher mix diet was achieved by chicken in Trial I under ORS than those under KS, as well as in starter mix diet in Trial III. Lighting program in Trial II had no effect on food conversion ratio and mortality of chicken. Feed density did not have an effect on final weights, feed conversion, mortality and production index. In chicken fed with meals with higher protein and energy content, higher weight was recorded at the end of the fattening period (P<0.01). Feed density in Trials I and III did not have an effect on feed conversion ratio, mortality and production index. Significantly higher weight was recorded in chicken fattened at the stocking density of 12 animals/m2 (2667.08 g) than at the density of 17 animals/m2 (2435.768g) and differences had statistically high significance. No effect of stocking density was identified in terms of feed conversion, mortality and production index.Factors analysed (light, feed density and stocking population) did not have an effect on carcass yield, but interactions of some of them did. In all the trials, a smaller share of abdominal fat was established under ORS than under KS, but it was not statistically significant. Feed density and stocking density had no effect on abdominal fat content. Higher abdominal fat content in all trials was found in female than in male chicken. The share of breasts is larger under KS than under ORS, but differences are statistically significant only in the Trial III. Feed density and stocking density had no effect on the share of breasts in the carcass. The share of drumsticks was higher in chicken fattened under ORS than those under KS, but differences were statistically significant only in the Trial I. The share of thighs in Trials I and II did not differ significantly between lighting programs, while in the Trial III it was higher under ORS than under KS (P<0.01). Effect of stocking density and feed density on the share of drumsticks and thighs was not determined. Higher share of drumsticks was determined in male chicken while in female, the share of thighs was higher.Relative values of conformation measures were not influenced by the light programs and feed density, except that in lower stocking density the relative value of the breast depth was higher (P<0.05). Effect of light and feed density on feet pads damage was not determined, but chicken in higher stocking density, as of 28th day, had significantly higher feet pad damage than those in lower stocking density.Light program and stocking density did not have an effect on physical properties of femur: cross-sectional area, breaking force and specific breaking force. Male chicken had larger cross-sectional area and femur breaking force, differences in cross-sectional area were statistically significant, but this was not the case with the breaking force.Percentage of fat in dark meat was higher and that of proteins lower under ORS than under KS. Other parameters of the chemical analysis of dark and white meat were not under the influence of the light programs. Feed density had no effect on chemical composition of breasts and thighs meat.Based on all stated above, it can be concluded that all three factors (light program, feed density and stocking density) as well as their interactions had effect on numerous production parameters and quality of broiler meat, including on their welfare in different fattening phases. Taking into account enormous differences in effects that may be achieved in different combinations of these factors, the results of these and similar researches should make easier the selection of the technology that would yield the best economic effects in chicken fattening. Furthermore, where results are unclear or contradictory, further research should be conducted on a larger number of animals and focus on economically more significant production and slaughterhouse characteristics of chicken.

Made available in DSpace on 2016-06-02T19:29:53Z (GMT). No. of bitstreams: 1 4559.pdf: 2430892 bytes, checksum: d154b35d326d05be2db06928cf07eaa6 (MD5) Previous issue date: 2012-05-30
Financiadora de Estudos e Projetos
As well as being popular and growing worldwide, sport fisheries are considered an important recreational, economic and social activity that propels a wide production chain and generates employment and income. The major species of marine shrimp used as live bait in the Brazilian coast used as live bait in sport fishing are: white shrimp Litopenaeus schmitti and pink shrimp Farfantepenaeus brasiliensis and Farfantepenaeus paulensis, all of them included in the list of overexploited species. Although the shrimp are caught in estuaries throughout the year, the main period of capture occurs in the summer months. This fact produces significant fluctuations in the catch throughout the year, occurring in situations that greatly reduced catches. In view of these facts, the cultivation of shrimps for bait production could become an important tool for conservation and regulation of the market for live bait. Thus, the studies that comprise this thesis were directed to the production of pink shrimp F. brasiliensis in biofloc system and management studies related to transportation of shrimp as live bait. From the results observed in thesis, it was observed that there is already a well established method for the production of post-larvae of F. brasiliensis this phase is not an obstacle for the production of live bait. Furthermore, the results show that F. brasiliensis has a potential for the cultivation in biofloc system and can be reared in a stocking density of up to 100 shrimp/m² during the nursery stage and in a density of up to 75 shrimp/m² during the grow-out phase. Finally, it was observed that for the transport of F. brasiliensis the water temperature should be between 16 and 19 °C and stocking density should not exceed 3 shrimp / L or (16.5 g / L), the transport is recommended for a maximum of 10 hours to prevent mortality. Therefore, according to all data obtained in this thesis, post-larvae production, cultivation in biofloc system and transportation of F. brasiliensis to be used as live bait proved to be technically viable solutions to meet the needs of sport fisheries.
Além de popular e crescente no mundo todo, a pesca amadora é considerada uma importante atividade recreativa, econômica e social que movimenta uma ampla cadeia produtiva gerando emprego e renda. As principais espécies de camarões marinhos nativos da costa brasileira utilizados como isca viva na pesca amadora são: o camarão-branco Litopenaeus schmitti e os camarões-rosa Farfantepenaeus brasiliensis e Farfantepenaeus paulensis, todas incluídas na lista de espécies sobre-explotadas. Embora os camarões sejam capturados em estuários ao longo de todo o ano, o principal período de captura ocorre nos meses de verão. Este fato produz flutuações significativas na captura ao longo do ano, ocorrendo situações em que as capturas diminuem muito. Em vista destes fatos, o cultivo de camarões para produção de iscas vivas pode vir a ser um importante instrumento para a conservação e para regulação do mercado de isca viva. Portanto, os estudos que compõem esta tese foram direcionados para a produção do camarão-rosa F. brasiliensis em sistema de bioflocos e para estudos de manejo relacionados ao transporte destes camarões como isca viva. A partir dos resultados observados na tese, pode se verificar que já existe uma metodologia bem estabelecida para a produção de pós-larvas de F. brasiliensis não sendo esta fase um obstáculo para a produção de isca viva. Além disso, os resultados mostraram que F. brasiliensis apresenta um potencial para o cultivo em sistema de bioflocos podendo ser cultivado na densidade de estocagem de até 100 camarões/m2 durante a fase de berçário e até 75 camarões/m2 durante a fase de engorda. Por último, observou-se que para o transporte de F. brasiliensis a temperatura da água deve estar entre 16 e 19 °C e a densidade de estocagem não deve ultrapassar os 3 camarões/L ou (16,5 g/L), sendo recomendado o transporte por no máximo 10 horas para evitar mortalidades. Portanto, de acordo com os dados obtidos na presente tese, a produção de pós-larvas, o cultivo em sistema de bioflocos e o transporte de F. brasiliensis para a comercialização na forma de isca viva para suprir as necessidades da pesca amadora demonstrou ser tecnicamente viável.

Inovação em produção animal tem sido cada vez mais exigido pelos consumidores. No ambito de produção de postura, a maior demanda é por ovos provenientes de sistemas alternativos às gaiolas tradicionais, majoritariamente pelas tendencias observadas na Europa, e dessa forma, pesquisas ressaltando a realidade brasileira estão sendo realizadas. O objetivo deste estudo foi avaliar parametros produtivos e de bem-estar em dois contextos de sistemas produtivos, sob variadas densidades de alojamento. Para isso 250 aves Lohmann Brown® foram distribuídas em delineamento inteiramente casualizado (DIC) com os tratamentos organizados em esquema fatorial 2 x 4, sendo 2 sistemas de alojamento (convencional e cage-free) e 4 densidades (375,00; 450,00; 562,50 e 750,00 cm2/ave), com 6 repetições. O período experimental foi de 21 a 36 semanas de idade das poedeiras, totalizando 4 ciclos de 28 dias cada. Foram avaliados desempenho produtivo (produção de ovos, consumo de ração, conversão alimentar por kg de ovos), qualidade de ovos (peso, coloração de gema, índice gema, % de gema, % albumen, % casca, espessura e resistência a quebra, e unidade Haugh) e indicadores de bem-estar (frequência respiratória e cardíaca, temperatura clocal, escore de lesão corporal, concentração d eIgY na gema) Observou-se interação entre sistema de produção e densidade de alojamento para: % postura, consumo de ração, conversão alimentar por kg de ovos, peso do ovo, % de gema, % albúmen, espessura de casca. O aumento de densidade promoveu efeito significativo para % postura, consumo de ração, temperatura cloacal, lesão em quilha e em pés. O tipo de sistema de produção afetou consumo de ração, conversão alimentar por kg de ovos, peso do ovo, coloração de gema, índice gema, resistência à quebra, frequência cardíaca temperatura cloacal, lesões de quilha e pés e concentração de IgY na gema. Os resultados deste estudo demonstram que tanto o sistema de produção quanto a densidade de alojamento estão ligados a efeitos produtivos, de qualidade de ovos, e de bem-estar animal.
Innovation in animal production has been increasingly demanded by consumers. In the field of egg production, the greatest demand is for eggs coming from alternative systems to traditional cages, mostly from the trends observed in Europe, and thus, research highlighting the Brazilian reality is being carried out. The objective of this study was to evaluate productive and welfare parameters in two contexts of productive systems, under different stocking densities. For this purpose, 250 Lohmann Brown® birds were distributed in a completely randomized design with treatments arranged in a 2 x 4 factorial scheme, with 2 housing systems (conventional and cage-free) and 4 densities (375.00; 450.00, 562.50 and 750.00 cm2 / bird), with 6 replicates. The experimental period was 21 to 36 weeks of age, totalling 4 cycles of 28 days each. (Egg weight, feed intake, feed conversion per kg of egg), egg quality (weight, yolk color, yolk index, % yolk,% albumen,% shell, shell thickness and resistance to breakage, and Haugh unit) and indicators of welfare (respiratory rate and heart rate, body temperature, body lesion score, IgY concentration in the yolk). The interaction between production system and housing density was observed for: % laying, feed intake , feed conversion per kg of eggs, egg weight, % yolk, % albumen, shell thickness. The increase in density had a significant effect on % laying, feed intake, cloacal temperature, keel and foot injury. The type of production system affected feed intake, feed conversion per kg of egg, egg weight, yolk color, yolk index, breaking strength, cloacal temperature, keel and foot lesions, and IgY concentration in the yolk. The results of this study demonstrate that both the production system and housing density are linked to productive effects, egg quality, and animal welfare.

Made available in DSpace on 2014-06-11T19:28:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-26Bitstream added on 2014-06-13T19:36:49Z : No. of bitstreams: 1 silva_wl_me_jabo.pdf: 738598 bytes, checksum: 3bab2246fd6bc478a66e3929f5f28058 (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
A produção de forragem é influenciada pelas estratégias de manejo impostas a ela, desta maneira, as técnicas para identificação do melhor momento para início e término do pastejo, aliadas aos estudos das características morfogênicas e estruturais das plantas, tornam-se úteis para direcionamento do manejo, pois buscam auxiliar no melhor entendimento do crescimento vegetal, e por conseqüência, da produção forrageira. O experimento foi realizado no setor de Forragicultura, em área pertencente à FCAV da UNESP – Jaboticabal no período de dezembro de 2008 a abril de 2009, com o objetivo de avaliar o efeito de índices de área foliar residual (IAFr) sobre as características morfogênicas e estruturais, além do acúmulo de forragem em pastos de Cynodon spp cv Tifton-85 sob regime de lotação rotacionada com ovinos. Os tratamentos foram constituídos por três IAFr, 2,4, 1,6 e 0,8, mantidos por regime de lotação rotacionada com ovinos. O delineamento experimental utilizado foi o de blocos completos casualizados em arranjo de parcelas subdivididas no tempo com sete repetições, totalizando 21 unidades experimentais. Foram avaliadas nas condições de pré e pós-pastejo, as alturas do dossel, os IAF e a massa de forragem, além da taxa de acúmulo de forragem e as características morfogênicas e estruturais dos pastos. No pré e pós-pastejo as alturas médias e o IAF do dossel se comportaram de forma análoga, decrescendo com a diminuição dos IAFr. O maior valor de interceptação luminosa no pós-pastejo (68,19%), foi verificado para o IAFr 2,4 e o menor valor (35,57%) para o IAFr 0,8. A taxa de aparecimento de folhas foi maior para o dossel mantido sob IAFr 0,8 em função da sua menor taxa de alongamento de colmos (0,51 cm/perfilho.dia). Os pastos mantidos sob IAFr 0,8 apresentaram maior densidade populacional de perfilhos. A massa de forragem seca...
The production of forage is influenced by handling strategies imposed on the techniques to identify the best moment for the beginning and ending of grazing, linked to the studies of morphogenetic and structural characteristics of plants, become useful tools for the directing of management for they aim to aid the best understanding of vegetal growth, and as consequence, forage plants. The experiment was conducted at Setor de Forragicultura at Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, at UNESP – Jaboticabal from December 2008 to April 2009, and aimed to evaluate the effect of residual leaf area index (LAIr) about the morphogenical and structural characteristics, and forage accumulation in pastures of Cynodon spp cv Tifton-85 in a rotational stocking system with sheep. The treatments were constituted by three LAIr, 2,4, 1,6 e 0,8, maintained by rotational stocking with sheep. A complete randomized block design was used arranged in sub-divided parcels with seven replications, totaling 21 experimental units. They were evaluated in pre and post-grazing conditions, the height of the sward, LAI and forage mass, besides the accumulation of forage rate and the morphogenetic and structural characteristics. In the pre and post-grazing, the average height and the LAI of sward, decreasing with the diminishing of LAIr. The biggest value of light interception in post-grazing (68,19%), was verified by LAIr 2,4 and the smallest value (35,57%) for LAIr 0,8. The stem elongation rate (0,51 cm/tiller.day). The grazing maintained by LAIr 0,8 had higher tiller population density. The total dry forage mass was 27,1% superior for LAIr 2,4 regarding to LAIr 0,8 in pre-grazing conditions, being this total production, 72,0% was composed by stem fractions and dead material. The biggest rates of dry matter accumulation were observed with LAIr 2.4, in the second and third grazing cycles... (Complete abstract click electronic access below)

Det kommer ske en stor utbyggnad av elektrolys för produktion av vätgas i Sverigeoch övriga världen. För att sänka produktionskostnaden och därmed göra vätgasenbilligare analyserar denna rapport vilket behov av syrgas och värme som en landbaserad fiskodling har, samt hur mycket syrgas och värme fiskodlingen skulle behövaköpa från en elektrolysör. Analysen visar att de arter som används i studien - tilapia(Oreochromis, Oreochromis,. Alcolapia), regnbåge (Oncorhynchus mykiss) och lax(Salmo salar) - i en odling som producerar 40 ton fisk om året skulle förbruka cirka1,16 procent av syrgasen och cirka 0,35 procent av värmen från en 3 MW PEMelektrolysör. Försäljningsvärdet av syrgasen och värmen från en 3 MW elektrolysörberäknas till cirka 695 000 SEK/år för syrgasen och cirka 1 830 000 SEK/år för värmen. Den genomsnittliga kostnaden för syrgas och värme för arterna i studien i enodling på 40 ton/år beräknas till 8900 SEK/år för syrgasen och 6400 SEK/år förvärmen i en landbaserad fiskodling.
There will be a major expansion of electrolysis for production of hydrogen in Sweden and the rest of the world. To reduce production costs and thus make hydrogencheaper, this report analyzes how much oxygen and heat a fish farm consumes andtherefore would need to buy from an electrolyser. The analysis shows that the species used in the study - tilapia (Oreochromis, Oreochromis, Alcolapia), rainbow(Oncorhynchus mykiss) and salmon (Salmo salar) - in a farm that produces 40 tonsof fish per year would consume 1.16 percent of the oxygen and 0,35 percent of theheat produced from a 3 MW PEM electrolyzer. The value of the oxygen and theheat from a 3 MW electrolyser is calculated at SEK 694,939/year for the oxygenand SEK 1,829,813/year for the heat. The average cost for the species in the studyin a 40 tonne/year fish farm is calculated at SEK 8,900/year for the oxygen and SEK6,400/year for the heat in a land-based fish farm.

Made available in DSpace on 2014-12-17T14:10:18Z (GMT). No. of bitstreams: 1 LigiaGR.pdf: 427991 bytes, checksum: fd90b864e24611c634c5ec114b00d8f7 (MD5) Previous issue date: 2008-08-29
The main problem faced by the shrimp industry are the infectious diseases. The hypodermal and hematopoietic necrosis infection (IHHN) is one of the major cause of disease in the cultured shrimp, Litopenaeus vannamei. Environmental changes involving water quality, oxygen concentration, salinity, temperature, stocking density, presence of pathogens, among others, triggering a stressing condition for the cultured shrimp, weakening them and allowing the outbreak of diseases. The stress on the animal leads to a change in the molecules immune response components, which can be used as indicators of shrimp health. Thus, the objective of the present study was to evaluate the effect of salinity, stocking density and IHHNV infection on the L. vannamei shrimp. The immune parameters used to check the shrimp health were the total hemocytes counts (THC), the agglutinating activity (AA) and the clotting time (CT) of the serum of shrimp. These parameters were analyzed in healthy and IHHNV-infected shrimp, grown in low (0-0.5 ), medium (19-24 ) and high (> 38 ) salinity, and extensive (7-12 cam.m-2), semi-intensive (15-25 cam.m-2) and intensive (33-45 cam.m -2) stocking density. The IHHNV infection rate was significantly higher in low salinity (P<0.005) and intensive density (P<0.005), both stressful conditions for L. vannamei. Low salinity significantly increased THC (P<0.05) and decreased and CT (P<0.05) in healthy and infected shrimp, but AA (P<0.05) significantly decreased in healthy shrimp at medium salinity. Culture intensification did not affect the THC, AA and CT of healthy and infected shrimp (P>0.05). The IHHNV infection did not affect any immune parameters of shrimp cultured at different salinities and stocking densities. It is necessary to emphasize that this study was conducted in shrimp grown in ponds, where several environmental factors are acting simultaneously. Thus, further studies are needed about the influence of other environmental factors on the immune parameters of shrimp cultured in pond
O principal problema enfrentado pela ind?stria do camar?o s?o as enfermidades de origem infecciosa. A Infec??o Hipodermal e Necrose Hematopoi?tica (IHHN) ? uma das principais causas de doen?as no camar?o de cultivo Litopenaeus vannamei. Altera??es do ambiente de cultivo envolvendo qualidade da ?gua, concentra??o de oxig?nio, salinidade, temperatura, densidade de estocagem, presen?a de pat?genos, entre outros, desencadeiam uma situa??o de estresse nos camar?es cultivados, debilitando-os e permitindo a instala??o de enfermidades. O estresse desencadeia no animal a altera??o de mol?culas componentes da resposta imune, que podem ser usadas como indicadores de sa?de do camar?o. Desta forma, o objetivo do presente trabalho foi avaliar o efeito da salinidade, densidade de estocagem e infec??o pelo IHHNV na imunidade do camar?o de cultivo L. vannamei. Os par?metros imunes utilizados para monitorar as condi??es de sa?de dos camar?es foram o n?mero total de hem?citos (THC), a atividade aglutinante (AA) e o tempo de coagula??o (TC) dos soros dos camar?es. Estes par?metros foram analisados em camar?es saud?veis e infectados pelo IHHNV, cultivados em baixa (0-0,5 ), m?dia (19-24 ) e alta (>38 ) salinidades e em extensiva (7-12 cam.m-2 ), semi-intensiva (15-25 cam.m-2) e intensiva (33-45 cam.m-2) densidades de estocagem. A taxa de infec??o pelo IHHNV foi significativamente maior em baixa salinidade (P<0,005) e na densidade intensiva (P<0,005), ambas condi??es estressantes para o L. vannamei. Baixa salinidade significativamente aumentou THC (P<0,05) e diminuiu TC (P<0,05) de camar?es saud?veis e infectados, mas AA (P<0,05) de camar?es saud?veis diminui significativamente na m?dia salinidade. A intensifica??o do cultivo n?o afetou THC, AA e TC de camar?es saud?veis e infectados (P>0,05). A infec??o pelo IHHNV n?o afetou nenhum dos par?metros imunes dos camar?es cultivados nas diferentes salinidades e densidades de estocagem. ? necess?rio enfatizar que o presente estudo foi realizado em camar?es cultivados em viveiros, onde v?rios fatores ambientais est?o atuando simultaneamente. Desta forma, s?o necess?rios estudos adicionais sobre a influ?ncia de outros fatores ambientais nos par?metros imunes de camar?es nas condi??es de cultivo

Dissertação de Mestrado, Aquacultura e Pescas, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2009
A nutrição é um elemento chave na larvicultura marinha e pesquisas recentes têm demonstrado as vantagens do uso de copépodes como alimento vivo. Acartia tonsa é uma espécie de copépode calanóide com elevado potencial de cultivo, mas cuja densidade de cultivo permanece como uma das principais restrições à sua futura produção comercial. Como tal, este estudo recorreu a uma abordagem integrada com vista a avaliar os efeitos da densidade de cultivo no crescimento, produção de ovos e sucesso de eclosão em A. tonsa. Verificou-se que o uso de densidades elevadas (6000 cop l-1) não apresenta efeitos deletérios no crescimento e desenvolvimento de copépodes, embora a mortalidade aumente significativamente, de ≤2.5 % d-1 a densidades de ≤1000 cop l-1 para 3.5-4.0 % d-1 a 3000-6000 cop l-1. A produção individual de ovos também diminuiu com o aumento da densidade, registando-se uma produção de 28.4±1.43 ovos fêmea-1 d-1 a densidades de 100 cop l-1 e de 7.13±0.61 ovos fêmea-1 d-1 a 2500 cop l-1. Para mais, registou-se um atraso na eclosão de ovos produzidos por adultos criados em culturas densas (500-2500 cop l-1), bem como ovos incubados a densidades elevadas (1.000.000 eggs l-1). Apesar dos efeitos negativos da densidade na sobrevivência, produção de ovos e sucesso de eclosão, a magnitude destes efeitos não compromete a produção a altas densidades. Pesquisas futuras deverão focar-se no melhoramento de sistemas de produção e metodologia de armazenamento de ovos, bem como nos processos que controlam a diapausa, já que a capacidade de produzir copépodes calanóides em larga escala representaria um avanço significativo no cultivo larvar de espécies marinhas.
Nutrition is a key element in marine larviculture and the use of copepods as live feed for marine fish larvae has been shown to have several advantages over traditional live preys. Acartia tonsa is a calanoid copepod with high culture potential, although culture stocking density remains a bottleneck to its future commercial production. Considering this, the present study took an integrated approach to provide further insight on the effects of A. tonsa stocking density on growth, egg production and hatching success. Increased stocking densities (6000 cop l-1) were shown to have no unfavorable effect on copepod growth and development. Nevertheless copepod mortality significantly increased with density, from ≤2.5 % d-1 at densities of ≤1000 cop l-1 to 3.5-4.0 % d-1 at 3000-6000 cop l-1. Individual egg production rate also decreased at higher stocking densities, with an egg production of 28.4±1.43 eggs female-1 d-1 at 100 cop l-1 and of 7.13±0.61 eggs female-1 d-1 at 2500 cop l-1. Delayed hatching was observed for eggs produced by adults grown in dense cultures (500-2500 cop l-1) and for eggs incubated at increased hatching densities (1.000.000 eggs l-1). In spite of the negative effect of stocking density on survival, egg production and hatching success, the magnitude of these effects does not compromise the profitable use of high density cultures. Future research should focus on the improvement of production systems and egg storage, as well as investigating the processes controlling egg diapause, since the ability to rear calanoid copepod species at large scale would present a major advancement in larviculture of marine fish species.

碩士
國立臺灣海洋大學
水產養殖學系
105
This research will focus on the Chinese Mitten Crab industry in Taiwan and take a closer look at the issues to search the key factor of the development. As a reference for industry development. Study the biological and economic information for the farming process by questionnaire survey, and apply a statistical theory to analysis. The results show that the average stocking density of the Chinese mitten crabs in Taiwan was 1,996 crabs/ha. The average culture cycle was 7.9 month and the average surival rate was 28.2％. According to the view of productice economics, the average cost about NTD 145,529 per ha, and NTD 208,495 per ha in stocking density≧2,500 crabs per ha as the cost highest and stocking density ＜1,500 crabs per ha as the cost lowest about NTD 107,931 per ha. The labor costs( NTD 92,279 per ha) was the major production in the unit costs of input and the feed cost( NTD 26,407 per ha) followed. Based on the profitability, the average total revenue was NTD 233,526 per ha, and NTD 87,997 per ha in net revenue. The benefit-cost ratio was 2.00. Overall, the profitability was highest at the stocking density 1,500～2,499 per ha (2.40) and the stocking density≧2,500 per ha 1.72 was lowest. The Chinese Mitten Crab industry in Taiwan development main problem is poor survival rate and poor management of farming costs. Decision on optimal stocking densities, improvements in farming technology, effective management of farming costs and establishmet of standard operating procedures for the Chinese mitten crabs farming. As the development to enhance the competitiveness of the Chinese Mitten Crab industry in Taiwan.

碩士
國立高雄海洋科技大學
水產養殖研究所
106
The study aims to develop the techniques for larvae rearing of Brindle Grouper (Epinephelus lanceolatus × Epinephelus fuscoguttatus) and investigate the effects of stocking density and feeding frequency on cannibalism. In experiment one, the effects of stocking density on survival, percent weight gain, feed intake, size heterogeity and cannibalism were examined. Six experiment groups were cultured for one week at different densities: 5 fish/L, 10 fish/L, 20 fish/L, 30 fish/L, 40 fish/L and 50 fish/L. The fishes were fed four times daily (6:00,10:00,15:00,19:00) to satiation. In experiment two, the effects of feeding frequency on survival, percent weight gain, feed intake, size heterogeity and cannibalism were examined. Four experiment groups were cultured for one week at same 40 fish/L density and were fed at different frequencies to satiation: 2 meals per day (6:00, 15:00), 4 meals per day (6:00,10:00,15:00,19:00), 6 meals per day (6:00, 9:00, 12:00, 15:00, 18:00, 21:00) and 8 meals per day (6:00, 8:00, 10:00, 12:00, 14:00, 16:00, 18:00, 20:00). The result suggests that rearing the larvae at 40 fish/L stocking density and 4~6 meals feeding frequency with a standard rearing operating procedure will reduce the cannibalism and increase the survival. It could improve the operating efficiency and facilitate the long term sustainability of the industry.

碩士
國立臺灣海洋大學
環境生物與漁業科學學系
101
In this study, two data-collection methods were used to examine the effects of different stocking density and feeding pattern on the growth and survival rate of the hard clam, Meretrix lusoria. The first method is artificial feeding, and the second is questionnaire. Two artificial feeding experiments were conducted. Experiment one is to examine the effects of three different stocking densities (80, 120 and 200 clam/m2) and two different feeding methods (artificial feed and algae water). Experiment two is to examine the effect of five different stocking densities (80,120, 200, 280 and 360 clam/m2) in fed water algae. The questionnaire was divided into three parts. The first part contains the farming experience, breeding pool age, breeding pool size, stocking size, sediment concentration, stocking density, feeding time, and the bottom sand layers drainage system. The second part contains the mixed breeding species and density mixed breeding. The third part contains the feeding category and feeding amount. The Multiple Regression Model was used to examine the effects of various factors on the growth and survival of the hard clam. According to the experimental results of artificial feeding, stocking density effect on growth rates was not significant (p>0.05). The first experimental results of two feeding modes, the AGR (shell length and weight) and the survival rate has significant difference, showed a better effect of feeding algae water for the hard clams. The results of multiple regression analyses indicated that the feeding with algae water, bottom sand layers drainage system were positively correlated to the growth rate. While, farming experience was negatively correlated to the growth rate. The species mixed breeding had no significant effect on growth. In addition, the pond size was positively correlated to the mortality rate but feeding with algal water was negatively correlated to the mortality rate. Both experiments and questionnaire indicated that stocking density had no significant effect on the growth rate of the hard clams, but feeding with algae water can promote the growth of the hard clams.

In land-based integrated aquaculture of marine finfish and macroalgae, rearing space is a large expense. Increasing algal stocking density can increase efficiency, but this may require greater irradiance because of self-shading. To determine the irradiance needed, experiments were conducted in one-litre flasks with enriched seawater under natural and artificial illumination. Under natural illumination, a Daily Photon Dose of 17 mol m-2 d-1 at 10 and 14 ºC, Palmaria palmata cultured at 10 g L-1 grew 100 % faster and absorbed 20 % more nutrients than Chondrus crispus. However, Atlantic halibut farm effluent can reach up to 19 ºC in summer, too high for P. palmata. Under artificial illumination, C. crispus performed better than under natural illumination. Light saturation curves indicated nutrient uptake by C. crispus at 10 g L-1 and 10 ºC was highest at 23 mol m-2 d-1 irradiance, equivalent to 400 µmol m-2 s-1 for 16 hours

Marketplace volatility in the pork industry demands that producers re-evaluate production practices in order to remain profitable. Stocking density and dietary energy concentration independently affect performance and economic returns of growing finishing pigs. However, there is limited information on whether the interaction between these two factors is important for optimizing productivity and maximizing economic returns. The objective of this study was to determine if the dietary energy concentration that maximizes performance and economic returns varies with stocking density. Treatments were arranged as a 2 × 3 × 3 factorial included; sex (barrows and gilts), dietary energy (2.15, 2.30 and 2.45 Mcal NE/kg) and stocking density (14, 17 or 20 pigs per pen providing 0.92, 0.76 and 0.65 m2 per pig, respectively). A total of 932 pigs were used with three replications of 18 treatments. Pigs were randomly assigned to pens within sex to achieve an average initial BW of 75 kg. Wheat and barley based diets were formulated to meet or exceed the pigs’ nutrient requirements (National Research Council, 2012) and were fed in three phases within sex at each energy concentration. Overall (75 to 118 kg BW), as dietary energy increased from 2.15 to 2.45 Mcal NE/kg, ADG increased from 1.17 to 1.23 kg/d, ADFI decreased from 4.09 to 3.77 kg/d, G:F improved from 0.29 to 0.33 and caloric intake increased from 8.81 to 9.29 Mcal NE/d (P < 0.05). When stocking density was increased from 14 to 20 pigs per pen, ADG (1.21 to 1.17 kg/d), ADFI (4.00 to 3.82 kg/d) and caloric intake (9.19 to 8.12 Mcal NE/d) decreased (P < 0.05). Neither dietary energy concentration nor stocking density had a significant effect on the utilization of calories for growth (Gain:Mcal). Feeder visits per pig and time at the feeder per pig were decreased when stocking density increased from 14 to 20 pigs per pen (P < 0.01). Total time at the feeder and time at the feeder per pig were increased when dietary energy decreased from 2.45 to 2.15 Mcal of NE/kg. Per pen, aggressive incidents at the feeder increased (P < 0.05) and there was a tendency for increased aggressive incidents per pig (P = 0.09) when stocking density was increased. There was a linear increase (P < 0.01) in income over feed cost (IOFC) with increased stocking density, and there was a tendency (P = 0.08) for a linear increase in IOFC when dietary energy was increased. The dietary energy which maximized the IOFC did not vary with stocking density. Dietary energy and stocking density independently affect pig performance, behavior, and economic returns and the optimal dietary energy does not depend on stocking density (dietary energy by stocking density interaction).

碩士
國立臺灣海洋大學
水產養殖學系
93
The experiment was undertaken to study the effect of body size and stocking density on ammonia excretion rate and oxygen consumption rate for Haliotis diversicolor supertexta. Three size of abalone (mean shell lengths: 3.5、5、7 cm) combined with different stocking density were reared in a small recirculating culture system maintained at 24-25℃. Ammonia excretion rate (MB (NH4)) and oxygen consumption rate (MB(DO)) were measured for three days continuously in order to found the relationship between specific ammonia excretion rate (S(TAN)), specific oxygen consumption rate (S(OUR)), BW (g) and D (abalone/m3). Abalone showed a diurnal cycle regular pattern in S(TAN) and S(OUR). Ammonia-N concentration was found varied in a range of 1.3~34.8 μg/L. S(TAN) of diurnal change varied in a range of 136.3~567.1 %. The oxygen concentration ranged 4.35~6.13 mg/L and S(OUR) of diurnal change ranged 128.0~363.5 %. Average S(TAN) by shell lengths (3.5、5、7 cm) were 4.16±0.8、2.7±0.3 and 2.4±0.3 mg/kg/hr. Means of S(OUR) were 284.5±55.4、247.8±14.7 and 212.0±8.9 mg/Kg/hr. The result concluded that the highest S (OUR) (S (H-OUR)) (mg/kg/hr), lowest S (OUR) (S (L-OUR)), means of S (OUR) (S (M-OUR)), density (D) (abalone/m3) and BW (g) is as following : S (H-OUR)= 624.9671-0.7503D-10.8926BW+0.0201BW×D R2 = 0.9177 S (L-OUR) =140.8128+0.0057BW×D R2 = 0.3504 S (M-OUR)= 415.9542-0.5095D-7.0676BW+0.0189BW×D R2 = 0.7214 On the other hand, the highest S (TAN) (S (H- TAN) ) (mg/kg/hr), the lowest S (TAN) (S (L-TAN)), the means of S (TAN) (S (M- TAN)), density (D) (abalone/m3) and BW (g) is as following : S (H-TAN)= 7.9748-0.000016D2-0.2814BW +0.0028BW2+0.0003BW×D R2= 0.8217 S (L-TAN4)= 1.2507+0.0272D-0.00008D2-0.1822BW+0.0006BW×D R2= 0.5781 S (M-TAN)= 5.5495-0.00002D2-0.1841BW+0.0004BW×D R2= 0.7114

碩士
國立臺灣海洋大學
水產養殖學系
94
Abstract This study investigated the effects of different stocking density and dietary seaweed sources on the growth and survival of juvenile Litopeaneus vannamei. Experiment I was conducted to evaluate the effects of stocking density on the growth and survival of juvenile Litopeaneus vannamei. Six different stocking densities (27.77 PL/m2 、55.55 PL/m2、88.33 PL/m2、111.11 PL/m2、138.88 PL/m2 and 166.66 PL/m2) of white shrimp were fed semi-purified diet (35% C.P and 6% crude lipid) for six weeks and detected ammonia every other day. After six weeks, the weight gain of white shrimps stocked with 27.77 PL/m2 was significantly higher than those of stocked with other densities. Survival of all treatments were above 80%. Experiment II was conducted to evaluate the effects of sources and levels of seaweed meal of hot-water extract on the dietary water stability and growth and survival of juvenile Litopeaneus vannamei. The semi-purified diets contained 3%、6% and 9% hot-water extract of dry powder of Ulva and Gracilaria, respectively. Diet, without hot water extract of dry powder of Ulva and Gracilaria was used as control. White shrimp fed control diet had the highest weight gain (805.6±48.7%), followed by shrimp fed with diet containg 6% Gracilaria (798.6±176.6%), and the lower weight gain of shrimp fed diet with 3% Ulva (721.9±99.2%). Survival of all treatments were above 93%. After four hours of water stability test, the control diet had the highest water stability 89.0% and diet with 6% Ulva had the lowest water stability. Experiment III was conducted to evaluate the effects of dietary seaweed on the dietary water stability and growth and survival of juvenile Litopeaneus vannamei. The semi-purified diet (35% C.P and 6% crude lipid) contained 6% of Ulva meal、Gracilaria meal、alginate、agar and carrageenan, respectively. The shrimps fed diets containing alginate and Ulva meal had the highest weight gain and those fed diet containg agar had the lowest weight gain. The diet containing Gracilaria meal had lower survival 50%. The water stabilities of diets containg agar and alginate were 92.6% and 92.2%, respectively.

There has been a continuous decline in both the production and general performance of the SRO in NSW estuaries over the past three decades. The relationship of this decline to both environmental and oyster-density related factors are assessed in this thesis. This question has been examined at different scales: a large scale that compares two different estuaries (Clyde and Shoalhaven Rivers, southern NSW); a regional scale that encompasses variations within an estuary and, at a lease scale that examines processes pertaining to individual or small groups of oysters. ... A set of environmental indices were used to complement the model and to assess the sustainability of the culture system. The combined indices indicated that while the ecological carrying capacity of the Clyde was exceeded the production capacity at an estuarine scale was not. On the lease scale, density experiments showed that while growth was not reduced as a result of current stocking densities, the condition index was significantly affected.

碩士
國立臺灣海洋大學
水產養殖學系
93
Two experiments were conducted on juvenile grouper Epinephelus coioides. Experiment 1 deal with the effects of feeding frequency, stocking density and fish size on growth and feeding behavior. The effect of feeding frequency, stocking density and fish size on body composition, growth, ammonia excretion, digestibility and feeding behavior were examined in experiment 2. Feeding frequency had positive effects on food consumption, growth and final size variation. Fish fed three times per day in both experiments showed better food consumption, but fed one meal per day in the 2nd experiment had better food conversion rate. In both experiments, fish size variation decreased with increasing feeding frequency and fish fed fewer meals per day tend to eat more per meal. Fish fed once daily had heavier stomach than from other groups. Fish fed three times daily had the highest body lipid content. Feeding frequency had no effect on apparent digestibility coefficient on grouper. Our result showed that a peak of ammonia excretion occurs 4 hours after the first feeding session. Increased feeding frequency to two or three lead to a cumulative effect of ammonia excretion. The low-density group had the highest food consumption as compared to medium and high densities in experiment 1. Fish stocked at high density had higher moisture content, stomachosomatic index, gut relative weight and condition factor. In experiment 1, the small size fish had higher size variation index compared to big size fish and had lower survival rate than medium and big fish. Our result indicated that fed three-time/ day for grouper grown from 10 to 30 g and one meal a day for the fish grown from 31 to 88 g, respectively and stocked at high density is recommended. Keywords: feeding frequency; stocking density; fish size; growth; body composition; feeding behavior; grouper.

碩士
國立東華大學
海洋生物多樣性及演化研究所
100
Macrobrachium rosenbergiis the world's breeding the highest amount of one of three prawns, but still need to improve the environment in shrimp nurturing and strengthening the management. To determine the optimal condition for larval culture of this speices, the effects of stocking density, water exchange rate, photosynthetic bacteria and algal addition on growth, survival and water guality of juveniles were assessed. Photosynthetic strains used the 16SrDNA sequence analysis and results confirm for Rhodobium sp. First, the effects of the photosynthetic bacteria (Rhodobium sp.) at concentrations of 0, 103, 104, 105, 106and 107cells mL-1 on the M. rosenbergii juvenile survival rate is recorded using a control tank with unchanged water and lacking photosynthetic bacteria and algae. The effect on the juvenile freshwater prawn is then calculated with variables such as density of prawn present at 7, 10, 13 and 16 juveniles L-1 and variations of photosynthetic bacteria. 0 juveniles L-1 is control. The effect on the juvenile freshwater prawn is calculated with different treatments are zero-exchange ,change water and gain photosynthetic bacteria. The results indicate that Rhodobium sp. had significantly higher survival rates in tanks with concentrations the other groups than those in the 0 and 103 cells mL-1 tanks (p＜0.05); the growth rates in the103 cells mL-1 tanks had significant (p＜0.05). The seven groups in NH3-N, NO2-N, NO3 -N, PO4-P had no significant differences (p＞0.05). The 7 juveniles L-1 also had significantly higher survival rates in the tanks with 13 and 16 juveniles L-1 tanks (p＜0.05); the growth rates had no significant differences (p＞0.05). The water quality present in the 0 tanks had lower levels of NH3-N, NO2-N, NO3 –N and PO4-P (p＜0.05). The survival rates in the zero-exchange and change water were not significant (p＞0.05); the growth rates in the treatments had no significant differences (p＞0.05). The water quality present in the NH3-N had no significant differences (p＞0.05); PO4-P and NO3 －N in the change water had lower significant(p＜0.05)and NO2 －N in the zero-exchange had higher significant(p＜0.05). This report indicates that the tanks prosper best with a concentration of R. orientis at 104 ~ 107 cells mL-1and juvenile prawns densities of 7 juveniles L-1; zero water exchange in the tank with photosynthetic bacteria and algal can maintain a stable.