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Published: 4 June 2021
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1

Mafiri, Matseko Nkele. "Effect of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of ross 308 broiler chickens." Thesis, University of Limpopo, 2014. http://hdl.handle.net/10386/1390.

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Thesis (M.Sc. (Animal Production)) -- University of Limpopo, 2014
Two experiments were conducted to determine the effects of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of supplementing diets with effective microorganisms on performance of unsexed Ross 308 broiler chickens aged one to three weeks. Two hundred unsexed day-old chicks were randomly assigned to five treatments with four replications, each replication having ten birds. A complete randomized design was used. The chickens were fed a grower diet supplemented with 0 (EM0), 30 (EM30), 50 (EM50), 70 (EM70) or 100 (EM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) diet and metabolisable energy intakes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate and live weight of the chickens. Poorer (P<0.05) feed conversion ratios were observed in chickens supplemented with effective microorganisms. However, effective microorganism supplementation improved (P<0.05) crude protein retention of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality rate of the chickens from 10 to 0 %. The second experiment determined the effect of supplementing diets with effective microorganisms on performance of male Ross 308 broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with four replications, each replication having 10 birds. The chickens aged 21 days, weighing 474 ± 2g, were allocated to the treatments in a complete randomized design. The chickens were fed a grower diet supplemented with 0 (EMM0), 30 (EMM30), 50 (EMM50, 70 (EMM70) or 100 (EMM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) intake, DM digestibility, metabolisable energy, feed conversion ratio, fat pad weight and meat sensory attributes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate, live weight and carcass weight of the chickens. However, effective microorganism supplementation improved (P<0.05) crude protein retention and crude protein content of meat of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality of the chickens from 5 to 0 %. v It is concluded that effective microorganism supplementation to the diets of Ross 308 broiler chickens reduced growth rate and live weight of the chickens. However, effective microorganism supplementation improved crude protein retention and crude protein content of the meat of broiler chickens. Supplementation with effective microorganisms reduced mortality of the chickens to zero.
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2

Sumadja, Wiwaha Anas. "Wheat starch digestibility in broiler chickens." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289079.

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3

Kafri, Ilan. "Skin breaking strength in broiler chickens." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54306.

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A procedure was developed to examine factors contributing to skin strength of meat-type chickens. Skin breaking strength was initially measured in lines of chickens divergently selected for high (H) and low (L) juvenile body weight, their reciprocal crosses (HL and LH), and an F₂ generation derived from HL and LH matings. Skin of chicks from the LL line was weakest, that from the HH and LH matings strongest, and that from HL and F₂ matings was intermediate. Percentage heterosis for breaking strength was significantly positive while percentage recombination was not significant. Skin breaking strength and protein, fat, moisture, and total collagen concentrations of skin from the breast, thigh, and back of male and female commercial broilers were then examined in response to diets containing relatively wide or narrow ratios of calories to protein (C:P). Comparisons were made at 28, 42, and 56 days of age. Chickens fed diets containing wider C:P ratios had weaker skin than those fed diets with narrower C:P ratios, with the differences being greater at older than at younger ages. Males had stronger skin than females. Among body sites, breast skin was stronger than thigh skin with that from the back being intermediate in strength. Skin breaking strength did not appear to be consistently associated with either the protein, fat, or collagen concentrations in the skin. Skin from broiler chicks fed diets with differing C:P ratios was also examined histologically. Males had stronger and thinner skin than females, with the differences in thickness due primarily to differences in the thickness of the hypodermis. Regardless of sex, feeding diets containing wider C:P ratios resulted in weaker and thicker skin. The thicker skin was associated with an increase in the thickness of the hypodermis and a decrease in the thickness of the dermis and epidermis. With the exception of differences between back and thigh skin, increases in breaking strength occurring between skin from different sites were associated with a reduction in total skin thickness and in the thickness of the hypodermis. It was concluded that increased hypodermis thickness and/or decreased thickness of the dermis and epidermis reduced skin strength. Two experiments were conducted in which skin strength was examined in relation to heat stress and supplemental ascorbic acid. In the first experiment, chicks fed diets containing 0 or 100 mg of ascorbic acid per kg of diet were subjected to either a constant ambient temperature of 23C, a constant ambient temperature of 32C, or a treatment consisting of 32C from 1600 to 1200 hr and 400 from 1200 to 1600 hr (32/400). Both heat stress and supplemental ascorbic acid tended to increase collagen concentrations in the skin, but differences in breaking strength were inconsistent in response to these treatments. Supplemental ascorbic acid, however, partially alleviated reductions in body weight due to heat stress but did not decrease body temperatures of heat-stressed chicks. In the final experiment, diets containing either 0, 200, or 400 mg/kg of supplemental ascorbic acid were fed to chicks maintained at ambient temperatures of 23 and 34C. Contrary to previous observations, ascorbic acid failed to ameliorate the depressive effect of heat stress on body weight. Supplemental ascorbic acid tended to reduce adrenal, bursa of Fabricius, and spleen weights but had no effect on heterophil and lymphocyte numbers or ratios. Adrenal ascorbic acid concentrations were not significantly affected by supplemental ascorbic acid and plasma ascorbic acid levels were inconsistent among treatment groups. Neither supplemental ascorbic acid nor heat stress significantly influenced skin strength. It was concluded that supplemental ascorbic acid was not beneficial in improving skin strength in commercial broiler chicks.
Ph. D.
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4

Dunaway, Andrew E. "METABOLIZABLE ENERGY DETERMINATION IN BROILER CHICKENS." UKnowledge, 2019. https://uknowledge.uky.edu/animalsci_etds/105.

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Feed accounts for the highest cost associated in poultry production, with energy-containing feedstuffs being the most expensive portion of the cost of feeding. The increasing demand for poultry meat gives reason to determine accurate apparent metabolizable energy (AME) values for various feedstuff through measuring energy utilization in the birds. The adaptation length of birds fed an experimental diet may affect the determined AME value due to the diet matrix and physiochemical properties of the feedstuff. Therefore, the objective of this thesis was to evaluate a select group of energy-containing feedstuff with different diets and with factors such as coccidia challenge and exogenous enzyme supplementation that may influence the determined AME values in broiler chickens.
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5

Nasril. "Continuous multi-phase feeding of broiler chickens." Texas A&M University, 2003. http://hdl.handle.net/1969.1/1640.

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Continuous multi-phase feeding of broiler chickens was evaluated to optimize broiler nutrition and minimize environmental impact related to excess nitrogen in poultry manure. Four experiments were conducted. Experiments 1 and 2 studied effects of continuous multi-phase feeding during a 3-week starting period using battery brooders while experiments 3 and 4 evaluated multi-phase feeding during a traditional 7-week growing period using both battery brooders and floor pens. In the first and second experiments, the nutrient content of the multi-phase diets was changed every 24 hours in comparison to single-phase feeding. Results indicated that during the starter period, continuous multi-phase feeding had no significant influence on feed consumption, daily gain, feed to gain ratio or fecal nitrogen. In the third and fourth experiments, a four phase industry type broiler feeding program was compared to intensive multi-phase feeding programs created by linearly blending three different diets based on typical industry nutrient values and a commercial nutrient modeling computer program (EFG Natal®). In both intensive multi-phase feeding programs, the diets were changed every three days over a 7-week growth period. Broilers in experiment 3 were raised in Petersime battery brooders to primarily access nitrogen balance while birds in experiment 4 were raised in a floor pen on pine shaving litter to resemble commercial broiler production. The results indicated that intensive multi-phase feeding improved body weight gain and feed to gain ratio only in weeks 5 and 6 but not during the overall 7-week period. Nitrogen excretion and nitrogen retention were unaffected by the intensive multi-phase feeding systems. Economic analysis indicated that intensive multi-phase feeding programs could potentially lower feed costs per kilogram of gain. However, the high cost of implementing a continuous multi-phase feeding system may not justify the relatively small gain in lower feed cost per kilogram of gain. In conclusion, continuous multi-phase feeding of broiler chickens using corn-soy diets does not appear to be justified by either increased performance or reduced nitrogen excretion.
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6

Van, Niekerk S. J. (Sarel Johannes). "Actual and predicted performance of broiler chickens." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49817.

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Assignment (MPhil)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: The aim of this study was to evaluate the performance and profitability of different dietary specifications for broiler chickens slaughtered at 35 days of age. Two trials were performed to evaluate different production parameters. The results of these trials were compared to the predicted results of the EFG broiler model. No carcass data were available for the two trials mentioned above. Therefore, in order to evaluate the accuracy of the broiler model when predicting carcass characteristics, two published data sets (Leeson et al., 1996a) were used. Predicted and actual values were compared, evaluated and discussed. Two broiler trials were performed. In Trial One the amino acid density decreased throughout the range of three treatments from prestarter to finisher diets. In Trial Two the amino acid density decreased only in the four finisher diets. The main difference between predicted and actual results was the response to body weight. The model predicted a steady increase in feed intake to compensate for the lower dietary specifications while body weight did not change significantly. This increase in feed intake seems to be enough to maintain body weight. Trial birds also increased their feed intake as dietary amino acid density decreased, but this compensation seemed to be too low to maintain body weight compared to the control diet. The birds may find it easier to compensate when they have time to adapt to the specification. There is evidence in the literature that birds need seven days to adapt their feed intake to a lower feed specification (Leeson et al., 1996a). It can be speculated that the trial birds started to loose body weight due to a lower amino acid intake in this period. The model seems to adapt feed intake immediately after a change in diet specification. The simulation on literature data lead to the following conclusions: 1) Broilers posses the capacity to increase their feed intake with at least 65% should finisher diets with lower amino acid and energy concentrations be supplied. If only the energy concentration of finisher diets were decreased, the increase in feed intake will be around 30%. (see Table 16 and 23) 2) The accurate prediction of feed intake from the given dietary specification has a major influence on the accuracy of the prediction of broiler performance. 3) Amino acid density and DLys:ME ratio plays a significant role in the control and prediction of feed intake. The EFG broiler model is based on sound scientific principles. The model is comprehensive and can be used for a wide range of environmental and management conditions as well as dietary conditions. The nutritionist can use the model with confidence to assist in practical feed formulation. The actual strength of the model lies in the time and money being saved compared to practical trials.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie is om die prestasie en winsgewendheid van braaikuikens te bepaal wanneer voere met verskillende digthede tot op 35 dae gevoer word. Twee eksperimente is uitgevoer om produksieresultate te evalueer. Die resultate van hierdie eksperimente is met die voorspelde waardes uit die EFG simulasie-model vergelyk. Aangesien geen karkasdata vir bogenoemde eksperimente beskikbaar was nie, is twee gepubliseerde datastelle gebruik om hierdie deel van die model te evalueer (Leeson et al., 1996a). Twee braaikuiken eksperimente is uitgevoer. Eksperiment Een het uit drie behandelings bestaan waarvan die aminosuur-konsentrasie vanaf dag een tussen behandelings verskil het. In Eksperiment Twee het die aminosuur-konsentrasie net in die vier afrondingsdiëte verskil. Liggaamsmassa op 35 dae het die grooste verskil tussen voorspelde- en werklike waardes getoon. Beide voorspelde en werklike innames het in albei eksperimente verhoog soos wat aminosuur-konsentrasie afgeneem het. Voorspelde liggaamsmassa het egter konstant gebly terwyl werklike data 'n afname in liggaamsmassa getoon het. Dit bleik dat die voorspelde toename in innames voldoende was om massa te onderhou terwyl die voëls in werklikheid nie genoeg gekompenseer het nie. Leeson et al., 1996a het tot die gevolgtrekking gekom dat braaikuikens minstens sewe dae benodig om hul voeriname by 'n nuwe spesifikasie aan te pas. So 'n stadige aanpassing kan daartoe lei dat energie- en aminosuur-inname daal indien 'n dieet met laer spesifikasie gevoer. Dit sal daartoe lei dat die kuikens liggaamsmassa verloor. Uit die literatuur simulasies is die volgende afleidings gemaak: 1) Braaikuikens besit die vermoeë om voerinname in die afrondingstyd met minstens 65% te verhoog indien 'n afrondingvoer met laer amiosuur- asook energiekonsentrasie gevoer word. Indien net die energiekonsentrasie verlaag word, sal die inname met sowat 30% verhoog. 2) Die akkurate voorspelling van inname is krities vir die akkurate voorspelling van produksieparameters. 3) Aminosuur-digtheid en DLys:ME speel 'n belangrike rol in die beheer en voorspelling van voerinname by braaikuikens. Die EFG braaikuikenmodel is op suiwer wetenskaplike beginsels geskoei. Die model is omvattend en kan vir 'n wye reeks van omgewings- en bestuurstoestande asook dieet-spesifikasies gebruik word. Die voedingkundige kan die model met vertroue gebruik om met praktiese voerformulering by te staan. Die model kan die formuleerder baie tyd spaar aangesien praktiese eksperimente ingeperk kan word.
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7

Molepo, Lephai Sarah. "Effect of moringa seed meal supplementation on productivity and carcass characteristics of ross 308 broiler chickens." Thesis, University of Limpopo, Turfloop Campus, 2014. http://hdl.handle.net/10386/1340.

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Thesis (MSc. Agriculture (Animal Production)) -- University of Limpopo, 2014
Two experiments were conducted to determine the effect of moringa seed meal supplementation on productivity and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of moringa seed meal supplementation on productivity of Ross 308 broiler chickens aged one to 21 days. Two hundred and fifty unsexed day-old Ross 308 broiler chicks were randomly allocated to five dietary treatments, replicated five times, and each replication having 10 chickens. A completely randomized design was used. The chickens were fed on a grower diet supplemented with 0 (M0), 5 (M5), 10 (M10), 15 (M15) and 20 (M20) g of moringa seed meal/bird/day. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, metabolisable energy intake, nitrogen retention, feed conversion ratio and live weight of unsexed Ross 308 broiler chickens. Moringa seed meal supplementation improved (P<0.05) growth rates of unsexed Ross 308 broiler chickens aged one to 21 days. A moringa seed meal supplementation level of 13.3 g/kg DM feed optimized growth rate of Ross 308 broiler chickens aged one to 21 days. The second experiment determined the effect of moringa seed meal supplementation on productivity and carcass characteristics of female Ross 308 broiler chickens aged 22 to 42 days. The chickens weighing 558 ± 10 g/bird were randomly allocated to five treatments with five replications having 10 birds. The chickens, aged 21 days, were allocated to the treatments in a completely randomized design. The chickens were fed on a grower diet supplemented with 0 (FM0), 5 (FM5), 10 (FM10), 15 (FM15) and 20 (FM20) g of moringa seed meal per kg DM. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake, carcass weight, breast meat weight, abdominal fat pad weight, liver weight, heart weight, thigh weight, meat flavour, juiciness and tenderness of female Ross 308 broiler chickens. However, moringa seed meal supplementation improved (P<0.05) nitrogen retention and gizzard weights of female Ross 308 broiler chickens. vi It was concluded that moringa seed meal supplementation improved growth rate of unsexed Ross 308 broiler chickens aged one to 21 days. Similarly, moringa seed meal supplementation increased nitrogen retention and gizzard weights of female Ross 308 broiler chickens aged 22 to 42 days.
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8

Nagaraj, Manonmani. "Evaluation of nutrition and management factors in the etiology of pododermatitis in broiler chickens." Auburn, Ala., 2006. http://repo.lib.auburn.edu/Send%206-15-07/NAGARAJ_MANONMANI_39.pdf.

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9

Huang, Huajin Kim. "Amino acid digestibility and performance of broiler chickens /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18475.pdf.

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10

Ngomani, Delisile. "Effect of dietary threonine level on productivity and carcass characteristics of Ross 308 broiler chickens." Thesis, University of Limpopo, 2019. http://hdl.handle.net/10386/3052.

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Thesis (M.Sc. (Animal Production)) --University of Limpopo, 2019
Two experiments were conducted to determine the effect of dietary threonine level on production performance and carcass characteristics of Ross 308 broiler chickens. In each experiment the diets were isocaloric and isonitrogenous but with different dietary threonine levels.The first part of the study determined the effect of dietary threonine level on feed intake, growth rate, mortality and carcass characteristics of Ross 308 broiler chickens aged between Day 1-21. A total of 150 unsexed day-old chicks were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having ten chickens per replicate. The second part of the study determined the effect of dietary threonine level on feed intake, digestibility, growth rate, mortality and carcass characteristics of male Ross 308 broiler chickens aged between Day 22-42. Seventy-five male chickens were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having five chickens per replicate. A quadratic regression model was used to determine the optimal productivity of the chickens while a General Linear Model (GLM) procedures for the statistical analysis of variance was used to detect dietary treatment effects. Where there were significant differences (P<0.05), Turkey’s honestly significant difference test (HSD) was used for mean separation. The chickens were slaughtered at the ages of 21 and 42 days for Experiments 1 and 2, respectively, following ethical standards as recommended by the University of Limpopo Animal Research Ethics Committee (AREC/12/2017: PG). Two chickens per replicate for both studies were slaughtered for the determination of carcass characteristics (carcass and organ weights, gut organ digesta pH and gastro-intestinal length measurements). Dietary threonine levels used in this experiment affected (P<0.05) feed intake, growth rate, live weight, metabolisable energy (ME) intake, nitrogen retention, feed conversion ratio and gut organ weights and lengths of unsexed Ross 308 broiler chickens aged 21 days. Dietary threonine level did not affect (P>0.05) diet digestibility. Feed conversion ratio, pH of the proventriculus digesta, gut intestine length and caecum length of unsexed broiler chickens were optimized at different dietary threonine levels of 9.6, 8.5, 6.6 and 8.4 g/kg DM, respectively. Dietary threonine levels had an effect (P<0.05) on feed intake, diet digestibility, metabolizable energy, live weight, proventriculus pH values, GIT length, gut organ and carcass organ weights of male Ross 308 broiler chickens between 22 to 42 days of age. Proventriculus and large intestine weights were optimized at different dietary threonine levels of 7.5 and 9.1 g/kg DM feed, respectively. Dietary threonine level did not affect (P>0.05) growth rate, feed conversion ratio of male Ross 308 broiler chickens between 22 to 42 days of age. It is concluded that dietary threonine levels used in this study affected production performance of younger broilers (Day 1-21) more than that of older birds (Day 22-42). However, production variables were optimized at different dietary threonine levels. This has implication on diet formulation for the chickens and no linear response could be established
National Research Foundation (NRF), and the Department of Agriculture, Forestry and Fisheries (DAFF)
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11

Desjardins, Paule. "Characterization of adipocyte adrenergic receptors in broiler chickens." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69595.

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Radioreceptor binding studies were carried out in broiler chickens in order to characterize adrenergic receptors on their abdominal fat adipocytes. The radioligands ($ sp3$H) DHA and ($ sp3$H) YOH were used to identify $ beta$- and $ alpha sb2$-adrenoceptors respectively. The determination of receptor criteria indicated that the optimal protein concentration for the simultaneous binding of both receptor types was between 0.35 and 1.0 mg/ml. Pharmacological specificity for both $ beta$- and $ alpha sb2$-adrenoceptors was demonstrated using receptor specific antagonists and an agonist. Saturation isotherms indicated that ($ sp3$H) DHA and ($ sp3$H) YOH labelled with high affinity, a homogenous population of non interacting $ beta$- and $ alpha sb2$-binding sites respectively. Scatchard analysis of the saturation data for ($ sp3$H) DHA revealed a Kd value of 8.1 nM and a Bmax value of 420 fmol/mg protein, while ($ sp3$H) YOH binding had a Kd value of 7.0 nM and a Bmax value of 68 fmol/mg protein. The variation in $ beta$- and $ alpha sb2$-adrenoceptor binding parameters was then investigated on the abdominal fat pad adipocytes of male and female broiler chickens at 4, 6 and 9 weeks of age. Scatchard analysis of the binding data for $ beta$-adrenoceptors indicated that Bmax values were greater in male and female broilers at 9 weeks of age (p $<$ 0.05) and that overall Bmax values were greater in females than in males (p $<$ 0.05). Scatchard analysis of $ alpha sb2$-adrenoceptor binding revealed that in females Bmax values remained constant but differed at all ages in males. The $ beta$-adrenoceptor Bmax values were always significantly greater (p $<$ 0.05) than the corresponding $ alpha sb2$-adrenoceptor Bmax values.
These results established for the first time the existence of adrenergic receptors on broiler chicken adipocytes using a radioreceptor binding assay. Although the physiological implication of these receptors is not known, it is a critical step toward the understanding of the influence of the adrenergic system on adipose tissue metabolism in avian species.
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Collins, Lisa M. "Non-intrusive social preference assessment in broiler chickens." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427885.

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13

Duggan, Jane A. "Aversion of broiler chickens to whole-body vibration." Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243677.

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14

Aitchison, Mia. "Energy efficiency and nutrient partitioning in the modern broiler chicken." Thesis, University of Aberdeen, 2014. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225709.

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15

Mokgope, Precious Kgomotso. "Effect of dietry carrot meal supplementation on productivity and carcass characteristics of arbor acre broiler chickens." Thesis, University of Limpopo, Turfloop Campus, 2014. http://hdl.handle.net/10386/1103.

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Thesis (MA. Agric. (Animal Production)) -- University of Limpopo, 2014
This study determined the effect of carrot meal supplementation on productivity and carcass characteristics of Arbor acres broiler chickens aged one to six weeks. Experiment I determined the effect of carrot meal supplementation on productivity of Arbor acre broiler chicks aged one to 21 days. Two hundred unsexed Arbor acre broiler chickens were randomly assigned to five treatments with five replicates, each replicate having ten birds. A completely randomized design was used in the first experiment. The treatments were 0 (UA0), 20 (AU20), 50 (AU50), 75 (AU75) or 100 (AU100) g of carrot meal supplementation per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged one to 21 days. Linear equations were used to determine relationships between carrot meal supplementation and productivity variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation, however, improved (P<0.05) metabolisable energy intake and nitrogen retention of the chickens. Dietary metabolisable energy intake and nitrogen retention of the chickens were optimized at different carrot meal supplementation levels of 40.5 and 53.57 g/kg DM feed, respectively. No chicken deaths were recorded. Experiment II determined the effect of carrot meal supplementation on productivity and carcass characteristics of female Arbor acre broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with five replicates, each having 10 birds, in a completely randomized design. The supplementation levels were 0 (FA0), 20 (FA20), 50 (FA50), 75 (FA75), or 100 (FA100) g of carrot meal per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention of broiler chickens aged 22 to 42 days. Linear equations were used to determine relationships between carrot meal supplementation and production variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and carcass parts of female Arbor acre broiler chickens aged 22 to 42 days. Carrot meal supplementation improved (P<0.05) feed intake, feed conversion ratio, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged vi 22 to 42 days. Dietary feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention were optimized at different dietary carrot meal supplementation levels of 52.8, 63.8, 38.0, 42.0 and 44.3 g/kg DM feed, respectively. Dietary carrot meal supplementation had no effect (P>0.05) on tenderness and flavour of female Arbor acre broiler meat. Broiler chickens on diets supplemented with 20, 50 or 100 g of carrot meal per kg DM feed produced meat with better (P<0.05) juiciness values than those of meat from chickens not supplemented with dietary carrot meal and those supplemented with 75 g/kg DM feed. There was a positive relationship between carrot meal supplementation and chicken meat juiciness. It is concluded that carrot meal supplementation improved (P<0.05) metabolisable energy intake and nitrogen retention of unsexed Arbor acre broiler chickens aged one to 21 days. However, carrot meal supplementation had no effect (P>0.05) on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation improved (P<0.05) intake, feed conversion ratio, metabolisable energy and nitrogen retention of female Arbor acre broiler chickens aged 22 to 42 days. However, carrot meal supplementation did not (P>0.05) improve growth rate and live weights of the chickens.
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Amwele, Hilma Rantilla. "The effect of ozone on the production of broiler." Thesis, Nelson Mandela Metropolitan University, 2004. http://hdl.handle.net/10948/226.

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The aim of the study was to evaluate the effect of ozone (O3) on mature body weight (MBW), feed conversion rate (FCR), mortality rate (MR) and ammonia (NH3) production of broiler chickens (referred to as “broilers” in this thesis) under controlled conditions. Ozone was used for the purifying of air and water in order to eliminate harmful microorganisms. Two trials were conducted over a twelve week production period. In experiment 1, day old broiler chicks were randomly allocated to a control (n=130) and treatment (n=130) group. The treatment groups were exposed to ozone continuously for the entire period of the trial. Both air and water were ozonated on a 24 hours daily basis, while the control group was reared under normal commercial conditions. In experiment 2: day old broiler chicks were randomly allocated to a control (n=123) and a treatment (n=123) group. The treatment group was exposed to ozone for 3 hours per day for the entire period of the trial. Both air and water were ozonated, where the air was treated for 3 hours/day and the water for 1 hour/day during the entire production period. The control group was reared under normal commercial conditions. The results indicate that broilers exposed to continuous O3 (0.1 ppm) conditions had significantly higher (P< 0.001) mortality rates than the control group. The treatment group had a mortality rate of 55.38% compared to the 5.38% for the control group. No significant difference (P= 0. 2468) for MBW was found between the broilers that were reared in the O3 environment compared to the control iii group. Although the control group were on average 200g heavier at the end of the trial. No significant difference (p = 0. 6143) was recorded in FCR between the O3 and control groups. However the FCR of the broilers treated with O3 was lower by 100g than that of the control group. The O3 significantly (P< 0. 0001) reduced the NH3 in the treatment group. When the trial was repeated with limited exposure to an O3 environment there was no significant difference in MBW (P = 0. 0979), FCR (P = 0. 8913) and MR (P = 0. 1108) between the treatment and control groups. However, ammonia levels were lower in the treatment group compared to the control group. When the data was further analyzed comparing the two trials, the results indicated that there was no significant difference (P = 0. 4112) in the MBW for the broilers reared under normal conditions (control group) from experiment 1 and experiment 2, while a significant difference (P = 0. 0002) was recorded between the broilers reared under continuous O3 and regulated O3 conditions from experiment 1 and experiment 2 respectively. When the FCR data was analyzed using the Gompertz equation a significant difference (P = 0.0403) in the FCR of broilers reared in the control group between experiment 1 and experiment 2 was recorded (Table 8). No significant difference (P = 0.3226) in the FCR of broilers raised under O3 conditions of continuous and regulated O3 production were reported between experiment 1 and experiment 2. A highly significant difference (P = 0. 0001) in the MR of broilers reared under ozone conditions was recorded between experiment 1 and experiment 2. In experiment 1, the MR was 55.38% while in experiment 2 the MR was only 8.78%. A significant difference (P = 0.0355) was also recorded in the MR of broilers that iv were raised in the control groups between experiment 1 and experiment 2. The MR for broilers in the control group was 5.38% in experiment 1 and for experiment 2 it was 9.74%. The mortality rate of broilers raised in the control groups conditions increased by approximately 4% points or 81% between experiment 1 and experiment 2. The level (0.1 ppm) of ozone production had a limited effect on the MBW and FCR of broilers, however it is evident that ozone is toxic to broilers when they are exposed to a continuous ozonated environment. Ozone was however effective in controlling ammonia levels.
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Albin, Gräns. "Feto-Maternal : Communication in Broiler Chickens (Gallus gallus domesticus)." Thesis, Linköping University, Department of Physics, Chemistry and Biology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-53989.

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Bird incubation is a natural phenomenon that balances the needs of the parents for nourishment with the needs of the fetus for heat provision and protection. In this context, any means of communication between the fetus and the parents would have an adaptive value. The aim of the study was to investigate whether putative means of fetomaternal communication would correlate to physiological changes caused by environmental alterations. Oxygen consumption was used to measure fetal well being and six independent variables associated with fetal vocalizations and fetal movements were used to evaluate their potential for communicating the fetus statu quo. Broiler fetuses (Gallus gallus domesticus) of three developmental stages (day 18, internally pipped and externally pipped) were challenged by a stepwise reduction in ambient temperature down to 30ºC. A linear drop in oxygen consumption in response to lowered temperatures was found in all three developmental stages indicating that the fetus was affected by the temperature changes. No differences correlating with temperature variations were found in any of the variables associated with fetal vocalization. Fetal vocalizations are consequently not used to communicate the thermal status of the fetus. Movement occurrence, movement intensity and ventilation frequency, however, followed a “maximum peak” trend, with a highest response at the third temperature interval (35.0-35.5ºC). Considering that the lower limit of optimal development is between 35-36ºC, the results suggest that fetal movements can be of potential use to the incubating parent to assess the well-being of the fetus.

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Wang, Pixian. "Assessment of factors influencing body composition of broiler chickens." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0020/NQ56640.pdf.

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19

Hall, Abigail. "The welfare of broiler chickens reared under commercial conditions." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249531.

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20

McNamee, Perpetua Therese. "Investigation of bacterial chondronecrosis with ostemyelitis in broiler chickens." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284361.

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21

Hilario, Reginaldo Francisco. "Statistical modelling of data from performance of broiler chickens." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11134/tde-18012019-165449/.

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Experiments with broiler chickens are common today, because due to the great market demand for chicken meat, the need to improve the factors related to the production of broiler chicken has arisen. Many studies have been done to improve handling techniques. In these studies statistical analysis methods and techniques are employed. In studies with comparisons between treatments, it is not uncommon to observe a lack of significant effect even when there is evidence to indicate the significance of the effects. In order to avoid such eventualities it is fundamental to carry out a good planning before conducting the experiment. In this context, a study of the power of the F test was made emphasizing the relationships between test power, sample size, mean difference to be detected and variance for chicken weights data. In the analysis of data from experiments with broilers with mixed sexes and that the experimental unit is the box, generally the models used do not take into account the variability between the sexes of the birds, this affects the precision of the inference on the population of interest . We propose a model for the total weight per box that takes into account the sex information of the broiler chickens.
Experimentos com frangos de corte são comuns atualmente, pois devido à grande demanda de mercado da carne de frango surgiu a necessidade de melhorar os fatores ligados à produção do frango de corte. Muitos estudos têm sido feitos para aprimorar as técnicas de manejo. Nesses estudos os métodos e técnicas estatísticas de análise são empregados. Em estudos com comparações entre tratamentos, não é incomum observar falta de efeito significativo mesmo quando existem evidências que apontam a significância dos efeitos. Para evitar tais eventualidades é fundamental realizar um bom planejamento antes da condução do experimento. Nesse contexto, foi feito um estudo do poder do teste F enfatizando as relações entre o poder do teste, tamanho da amostra, diferença média a ser detectada e variância para dados de pesos de frangos. Na análise de dados provenientes de experimentos com frangos de corte com ambos os sexos e que a unidade experimental é o boxe, geralmente os modelos utilizados não levam em conta a variabilidade entre os sexos das aves, isso afeta a precisão da inferência sobre a população de interesse. Foi proposto um modelo para o peso total por boxe que leva em conta a informação do sexo dos frangos.
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22

Molepo, Lephai Sarah. "Effect of moringa seed meal supplementation on productivity and carcass characterictics of ross 308 broiler chickens." Thesis, University of Limpopo, 2014. http://hdl.handle.net/10386/1363.

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Thesis (MSC. Agriculture (Animal Production)) --University of Limpopo, 2014
Two experiments were conducted to determine the effect of moringa seed meal supplementation on productivity and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of moringa seed meal supplementation on productivity of Ross 308 broiler chickens aged one to 21 days. Two hundred and fifty unsexed day-old Ross 308 broiler chicks were randomly allocated to five dietary treatments, replicated five times, and each replication having 10 chickens. A completely randomized design was used. The chickens were fed on a grower diet supplemented with 0 (M0), 5 (M5), 10 (M10), 15 (M15) and 20 (M20) g of moringa seed meal/bird/day. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, metabolisable energy intake, nitrogen retention, feed conversion ratio and live weight of unsexed Ross 308 broiler chickens. Moringa seed meal supplementation improved (P<0.05) growth rates of unsexed Ross 308 broiler chickens aged one to 21 days. A moringa seed meal supplementation level of 13.3 g/kg DM feed optimized growth rate of Ross 308 broiler chickens aged one to 21 days. The second experiment determined the effect of moringa seed meal supplementation on productivity and carcass characteristics of female Ross 308 broiler chickens aged 22 to 42 days. The chickens weighing 558 ± 10 g/bird were randomly allocated to five treatments with five replications having 10 birds. The chickens, aged 21 days, were allocated to the treatments in a completely randomized design. The chickens were fed on a grower diet supplemented with 0 (FM0), 5 (FM5), 10 (FM10), 15 (FM15) and 20 (FM20) g of moringa seed meal per kg DM. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake, carcass weight, breast meat weight, abdominal fat pad weight, liver weight, heart weight, thigh weight, meat flavour, juiciness and tenderness of female Ross 308 broiler chickens. However, moringa seed meal supplementation improved (P<0.05) nitrogen retention and gizzard weights of female Ross 308 broiler chickens. vi It was concluded that moringa seed meal supplementation improved growth rate of unsexed Ross 308 broiler chickens aged one to 21 days. Similarly, moringa seed meal supplementation increased nitrogen retention and gizzard weights of female Ross 308 broiler chickens aged 22 to 42 days.
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23

Prince, Siliga Hulisani. "Modelling the broiler performance under small-scales and semi commercial management condition." Thesis, Port Elizabeth Technikon, 2002. http://hdl.handle.net/10948/110.

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Introduction : World poultry meat consumption consists of three major segments: broilers, turkeys, and other poultry which includes spent egg layers, spent breeder hens/males, ducks, geese, guinea-fowl, pheasants, quail, ratites, ostriches and emus. Broilers clearly dominate the world poultry consumption contributing about 70 percent to the world poultry market. Turkeys account for about eight percent while other poultry provides the balance of 22 percent (Roenick, 1998). The world broiler industry has been, and continues to be a very dynamic industry. It has been typified with unprecedented growth in terms of production. In 1961, the world produced 6.5 billion broilers. By 1990, the total annual production was a little over 27 billion broilers and by 1996, total world production had grown to 35.3 billion (Van der Sluis., 1999). This represents a fivefold increase in 35 years, and it has not stopped growing since, with world production surpassed 38 billion in 1998 (Van der Sluis., 1999). In Africa the human population was estimated to be 819.9 million, while the total poultry population of the continent was estimated as 1.133 million chickens, 15 million ducks and seven million turkeys in 1998. Production scale being 1.781701 metric tones (MT) of hen eggs, 2.269000 MT of chickens’ meat, 32.824MT of turkey meat and 52.989MT of duck meat (Gueye, 2000). Commercial poultry products are also imported and exported. For example, 12.000 metric tons of poultry meat was estimated to have been exported from South Africa in 1999, whereas 87.000 and 10.000 metric tons of poultry meat was imported into South Africa and Egypt, respectively (Gueye, 2000). In South Africa poultry production is moving toward the 21st century with the potential for increased development being greater than any other sector of the agricultural industry. The small-scale to medium-scale or semi-commercial farmer is becoming a role-player that needs to be serviced by the poultry industry (Fourie, 2000). The industry will have to take up the challenges that are facing an entrepreneur starting with a poultry venture. The poultry industry has developed from a humble beginning at the turn of the century into a multi-million Rand enterprise where protein is provided through the commercial and small marketing sector (Fourie, 2000). Some of the larger commercial companies market three million birds per week. It is estimated that the commercial company sector is responsible for 75 to 85 percent of production and marketing of white meat in this country whereas the small-scale and medium-scale or semi commercial poultry production enterprises provide 20 to 25 percent of the white meat through the sales of slaughtered and live poultry sale to rural, peri-urban and urban settlements (Fourie., 2000). Small-scale and semi-commercial broiler production is developed by entrepreneurs who buy day-old chicks from the big commercial hatcheries, rear them to the age of five to eight weeks and sell them through a marketing network or small outlets. The small-scale consist of farmers who reared 100 t0 1000 chickens per batch and semi-commercial consist of farmers who reared 1000 to 5000 chickens per batch. These types of farmers acquire very little technical backup in terms of a training and services center where assistance is available every day of the week. The broiler industry requires birds that are of commercial crosses selected for their ability to grow very fast and produce a good quality carcass in the shortest time frame. The small farmers purchase broiler stock, as the day-old chicks from commercial hatcheries and reared them up to six to eight weeks before slaughtered or sold as live chickens. The selling of live chickens through a network outlets system is becoming an industry that is growing at a steady pace, as household food security is becoming important to communities (Fourie, 2000). The price of feed is the single most expensive item on the list of expenses of a farmer because of their financial constraints. The small-scale and semicommercial broiler farmer is faced with the problem of buying small quantities of feed at an inflated price. The problem can be alleviated by groups of small farmers joining co-operative and buying feeds in bulk from suppliers and redistributing to small farmers. The community co-operative can once again play a major role in the distribution of small amounts of feed to its member. The biggest challenge is to provide training with a “hands on” approach. It will be ideal to have a training center where small farmers can be trained in all aspects of poultry production. The training facility will have to operate as a fully operational poultry unit with no risks to bio-security of a commercial enterprise. Training will have to be provided in aspects like hatchery, housing, broilers and record management depending on the farmer’s needs. There is also a need for the research on broiler performance under small-scale and semi commercial farming. Research in this sector of poultry production should look in appropriate feeds, feeding, technology, genotype and performance of genotypes under the system. Emphasis in this study will be on growth patterns and performance of the Ross hybrids as a modern broiler under small-scale and semi commercial management condition. Aspect of the environment such as age, type of feeds and feeding methods, housing, seasons, lighting and genotype will be taken into consideration. The result of the study will provide a realistic database for mathematical modeling of production response and guideline for management planning in small-scale and semi-commercial management condition. Also this result will be important to broiler breeders, to determine the suitability of the modern broiler to small-scale and semi commercial management conditions. The objective of the study was to evaluate the mathematical model that could describe the performance of broilers under the small-scale and semi-commercial management conditions.
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24

Sherlock, Louise. "Gene expression and behavioural responses of broiler chickens to production-based stressors." Thesis, Royal Veterinary College (University of London), 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558989.

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25

Cruickshank, John Johnston. "Morphometric and radiographic characterization of leg disorders in broiler chickens." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24601.

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The objective of this study was to investigate the effects of cage density and excess vitamin D₃ on the incidence and severity of leg abnormalities in broiler chickens. In addition, sequential morphometric and radiographic characteristics of leg bone development were described in normal and abnormal broilers in an attempt to develop a pattern recognition for leg abnormalities in poultry. Twisted leg, characterized by a progressive medial (varus) or lateral (valgus) deviation of the distal tibiae was the predominant leg abnormality observed. Lateral deviations were more common than medial deviations (92% and 8%, repectively) and it occurred equally on the right and left leg. The incidence of twisted leg was considerably higher in cages than on litter (21% vs 4%, respectively). High density and excess dietary vitamin D₃ resulted in a significant increase in the incidence of twisted leg. Differences in incidence could not be explained through differences in body weight or feed consumption. However, broilers fed the excess vitamin D₃ consumed more but gained less body weight, suggesting a metabolic stress may have been involved. High density appeared to increase the severity of the disorders, while excess vitamin D₃ had no effect on severity. Morphometric and radiographic comparisons of tibiae from normal broilers and those with twisted leg suggested that the development of twisted leg may be related to a structural abnormality in the distal tibiae; namely shallow distal condyle grooves. Changes in tibiae morphology associated with the progression of the disorder appeared as functional adaptations to the deformation rather than the primary cause of the bone deviations themselves. Sequential radiography of tibae from clinically normal broilers revealed a high incidence of tibial dyschondro-plasia in the proximal metaphyses at 3, 4 and 5 weeks (60%, 20% and 20%, respectively). It was concluded that tibial dyschondroplasia may be more common than it is realized.
Land and Food Systems, Faculty of
Graduate
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26

Boychuk, Janet Lee Lynn. "Evaluation of micronized dehulled barley for pigs and broiler chickens." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23232.pdf.

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27

Drakley, Catherine. "The dietary energy value of wheat for young broiler chickens." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391650.

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28

Petersen, Suzanne Tove. "The implications of cereal non-starch polysaccharides for broiler chickens." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339600.

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29

Waldron, Lucy Anne. "The nutritive value of different wheat varieties for broiler chickens." Thesis, Open University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338547.

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30

Bailey, Richard. "Intestinal microbiota and the pathogenesis of dysbacteriosis in broiler chickens." Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/33034/.

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31

Queiroz, MarÃlia Lessa de Vasconcelos. "Thermal comfort of broiler chickens in sheds with misting system." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12708.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
Para os animais expressarem melhor suas caracterÃsticas genÃticas à necessÃrio que estejam em um ambiente favorÃvel para isso. Apesar de no Estado do Cearà haver condiÃÃes ambientais favorÃveis à produÃÃo de frangos de corte, as temperaturas elevadas predominam durante todo o ano. O mecanismo de controle da temperatura corporal das aves sà à eficiente quando a temperatura do ambiente se encontra dentro de certos limites. A combinaÃÃo de elevadas temperaturas e elevada umidade relativa do ar pode afetar o bem-estar das aves e se tornar um fator limitante para a produÃÃo. Sendo assim, o objetivo deste trabalho foi avaliar o ambiente de galpÃes avÃcolas, medindo temperatura e umidade relativa do ar para o cÃlculo do Ãndice Entalpia de Conforto, assim tambÃm como a mediÃÃo da temperatura da cama das aves, luminosidade e velocidade do vento para elaboraÃÃo de mapas de krigagem, assim tambÃm como monitorar variÃveis fisiolÃgicas (temperatura retal e frequÃncia respiratÃria), o comportamento das aves e o ganho de peso. As avaliaÃÃes foram feitas durante a Ãpoca seca, no perÃodo da manhà e da tarde, em dois galpÃes idÃnticos, atravÃs de ferramentas da zootecnia de precisÃo. Os dados de temperatura da cama, luminosidade e velocidade do vento foram analisados atravÃs da geoestatÃstica e, posteriormente, foram elaborados mapas com os perfis da distribuiÃÃo espacial destas variÃveis ao longo dos galpÃes. Com os mapas foi possÃvel observar que em alguns locais a temperatura da cama das aves apresentou valores muito elevados, chegando a 33,8 oC aos 42 dias de uso do galpÃo, temperatura considerada elevada e que pode gerar desconforto tÃrmico Ãs aves e prejudicar as trocas tÃrmicas por conduÃÃo. Os mapas de krigagem tambÃm mostraram que o sistema de ventilaÃÃo nÃo distribuiu a ventilaÃÃo de forma homogÃnea. A maior mÃdia da velocidade do vento foi 2,6 m.s-1. As medidas da temperatura retal e da frequÃncia respiratÃria das aves na 5 e 6 semana foram consideradas elevadas e indicaram uma condiÃÃo de estresse tÃrmico. A avaliaÃÃo do etograma demonstrou que as aves diminuÃram o tempo gasto na alimentaÃÃo e aumentaram o tempo de Ãcio, da 5 para a 6 semana. Esta queda no consumo provavelmente aconteceu devido à condiÃÃo de estresse tÃrmico a que as aves estavam submetidas. Todos esses fatores avaliados refletiram negativamente no ganho de peso dos animais, que tiveram o peso abaixo do esperado para a linhagem estudada.
For animals express their best genetic traits, they need to be in a favorable environment. The state of the Cearà has favorable environmental conditions for the production of broilers, but high temperatures prevail throughout the year. The mechanism control of the temperature of the body of birds is only effective when the ambient temperature is within limits. The combination of high temperatures and high relative humidity can affect the welfare of the birds and become a limiting factor for production. Thus, the aim of this study was to evaluate the environment in shed of the birds, realize measuring of the temperature and relative humidity for the calculate the Enthalpy Comfort Index (IEC), also measure the temperature of the Litter, wind speed and luminosity for drafting of kriging maps, also monitor physiological variables (rectal temperature and respiratory rate), the birds' behavior and weight gain. Evaluations were made during the dry season, during the morning and afternoon, in two similar shed of the birds, through tools of animal precision. The temperature data of Litter, wind speed and luminosity were analyzed using geostatistics and subsequently maps with profiles of the spatial distribution of these variables over the sheds were prepared. With the maps it was observed that in some places the temperature of the Litter showed very high values, reaching 33.8 ÂC after 42 days. This temperature was considered high and can cause thermal discomfort to birds and harm the exchanges thermal by conduction. The kriging maps also showed that the ventilation system not distributed homogeneously the ventilation. The highest average wind speed was 2.6 ms -1. Measurements of rectal temperature and respiratory rate of birds in the 5th and 6th week were considered high and indicated a heat stress condition. The evaluation of the ethogram showed that the birds reduced the time spent feeding and increased leisure time, between the 5th to 6th week. This fall in consumption probably happened due to condition of heat stress that birds were submitted. All these factors evaluated negative ly reflected in weight gain of the animals, which had the weight lower than expected.
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32

Pisula, Anneka. "Detecting a Probiotic Product Within the Gut of Broiler Chickens." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1921.

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As of January 2017, the U.S. poultry industry banned the use of antibiotics and now relies on alternatives such as probiotics to help protect animal health. Although probiotic use is not a new concept in the poultry industry, identifying the best combination of bacterial strains to generate an effective probiotic formula requires further investigation. This study aimed to detect a probiotic product of four bacterial strains (Pedioccoccus acidilactici, Pediococcus pentosaceus, Lactobacillus plantarum, and Bacillus subtilis) in a feeding trial with broiler chickens. Birds given the probiotic were predicted to show an improved growth performance with the probiotics colonizing the gut. Ninety-six broiler chickens were equally divided into 3 treatment and 3 control pens. During the 25-day experiment, birds were fed a starter diet (days 0-11) and a grower diet (days 12-25). Experimental birds were administered the probiotic product via the drinking water at a concentration of 3.1×104 CFU/ml. Control birds had an equivalent amount of dextrose filler added to their water supply. Feces were collected hourly on day one and daily thereafter. On days 1, 22, and 25 of the experiment, 2 birds from each pen were euthanized for gut sampling. Lumen and mucosa samples were collected from the duodenum, jejunum, ileum, and ceca. Species-specific and strain specific PCR primers were employed for probiotic detection. Wild strains of P. acidilactici, P. pentosaceus, and L. plantarum were detected in the feeds, inhibiting detection of the probiotic strains when using species-specific PCR primers. Strain-specific primers were used to detect the probiotic Pedioccoccus acidilactici and Lactobacillus plantarum strains. B. subtilis was detected in feces within one hour of probiotic administration and was predominantly detected in experimental birds only. Both P. acidilactici and L. plantarum probiotic strains were initially detected in the feces of treated birds within two hours of probiotic administration and again ten days later. Both L. plantarum and B. subtilis were seen only in treated bird gut samples. L. plantarum was predominantly detected in the ceca near the end of the small intestine. P. pentosaceus was observed more often in treated gut samples and P. acidilactici was the least commonly detected probiotic strain. All administered bacteria were rarely seen in mucosa samples. Feed-endogenous P. acidilactici and L. plantarum strains became progressively more detectable in the mucosa along the gastrointestinal tract suggesting gut colonization, however, probiotic strains did not appear to colonize the mucosa of treated birds. Although probiotic strains were no longer detected after product removal, all probiotic strains were detected in feces and gut samples during probiotic administration, suggesting the bacteria can colonize the gut. Probiotic supplementation did not result in significant differences in body weight gain, feed intake, or feed conversion ratio. However, birds growing in a more stressful environment than the carefully controlled experimental set up used here may show probiotic-related effects. This study identified that the probiotic bacteria appeared to survive the gastrointestinal tract, exhibited a transit time of 1-2 hours, could possibly colonize chickens, and localized near the end of the chicken gut.
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33

Law, Bibiana Felicity. "Assessment of the pathogenicity of Campylobacter jejuni from broiler chickens." Diss., The University of Arizona, 2005. http://hdl.handle.net/10150/282899.

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Sixty-three of 435 (14.5%) samples collected from broiler chickens were positive for C. jejuni. Twenty-two of 55 samples were from organic chickens (40%) and 41 of 380 samples were from conventional chickens (10.8%). Isolates were subjected to macrorestriction profiling using SmaI and analyzed for their ability to survive in macrophage cells and invade in epithelial cells. Antibiotic testing to cefaclor, ciprofloxacin, tetracycline, erythromycin, gentamicin, trimethroprim/sulfamethoxazole, and ampicillin were performed. Finally, 5 isolates of varying putative in vitro virulence traits were chosen for experimental inoculation of newborn piglets. Five piglets per isolate were tested and examined macroscopically and microscopically upon necropsy. Genotyping of isolates indicated 1 to 3 profiles per flock. Of the 22 organic isolates from chickens, only 3 (13.6%) were able to survive within macrophages. For the conventional isolates, 21 out of 41 (51.2%) were able to survive. However, the majority of isolates (90.5%) from both organic and conventional isolates were not capable of invading epithelial cells. No isolates exhibited resistance to ciprofloxacin or gentamicin. One isolate out of 63 (1.6%) was resistant to erythromycin, 52 (82.5%) to tetracycline, 28 (44.4%) to trimethroprim/sulfamethoxazole, and 6 (9.5%) to cefaclor. In terms of the piglet studies, regardless of the combination of in vitro invasion or survival results or type of flock, most piglets (16/25) in all groups exhibited hyperemia, edema, and hemorrhage in the small intestine or colon upon gross examination. Microscopic examination revealed congested mucosa and erosion of the epithelium in 10 of the 25 piglets from 4 of the 5 groups. In conclusion, this study suggests that C. jejuni isolated from broiler chickens are virulent in piglets and are probably capable of causing disease in humans. Furthermore, the results of the survival and invasion assays did not correlate with the results of the piglet studies and cannot be relied upon to predict degree of virulence. Therefore, another virulence factor is responsible for the pathogenesis, such as a toxin(s). As this is the first study to confirm putative in vitro virulence traits with an animal model, further research is recommended with the piglet model to assess pathogenicity.
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Nembilwi, Daniel. "Evaluation of broiler performance under small-scale and semi-commercial farming conditions in the Northern Province." Thesis, Port Elizabeth Technikon, 2002. http://hdl.handle.net/10948/92.

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Introduction: In the Northern region of the Northern Province, there is an increase in the number of small-scale and semi-commercial farms in all sectors of agriculture. This includes the production of grains, vegetables, fruits and livestock. Broiler production seemed to be a much-preferred alternative of development in community based projects and emerging farmers have shown keen interest. This is because broiler production requires less space than ruminants and is ready for human consumption within a very short period of time. Poultry production provides a constant source of income and protein with a big customer demand. By the year 2000, broiler production is expected to reach 4000 million and 7.5 million tons of poultry feeds in the world. Many countries have initiated programs aimed at improving small-scale poultry as a means of helping to bring socio- economic benefits to rural communities (Panda, 1989). In order to feed the ever rising population of 4.9 million in the Northern Province (1996 Census), there must be an increase in the production of broilers as a primary source of top quality animal protein. With the high unemployment rate (46%) in the Northern Province, self- employment projects are needed which comply with agro- processing. More than 90 community projects based on poultry production in the Northern region of the Northern Province had been established in order to reduce the high rate of unemployment. Today more people have engaged themselves in community projects especially in poultry production than ever before. Some of the constrains of broiler production at both small-scale and semi-commercial farming condition includes inadequate ventilation system. Lack of suitable health care facilities and frequently the absence of efficient marketing structures form part of the obstacles to the rapid development of poultry production. Feed costs which remain the highest input cost in the production of broilers represent between 60 to 70% or more of the total costs of broiler productions (Benyi and Habi, 1998). Lack of management skills and training for small and semi-commercial farmers makes it difficult to obtain optimum performance. The objective of this study is to evaluate the performance of broilers as influenced by environmental factors under small.
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35

Mohlapo, Teboho Daniel. "Effect of Hoodia Gordonii meal supplementation at finisher stage on productivity and carcass characteristics of Ross 308 broiler chickens." Thesis, University of Limpopo, 2009. http://hdl.handle.net/10386/496.

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Thesis (Bsc. (Animal production)) --University of Limpopo, 2009.
Two experiments were conducted to evaluate the effect of Hoodia gordonii meal supplementation at finisher stage on productivity and carcass characteristics of Ross 308 broiler chickens. Experiment 1 examined the effect of levels of Hoodia gordonii meal supplementation of grower diet fed to Ross 308 broiler chickens at the finisher stage (30 – 42 days of age) on productivity and carcass characteristics in a 12 day experimental period. The experiment was a completely randomized design with a 2 (two sexes of chickens) x 6 (levels of Hoodia gordonii meal [0, 100, 200, 300, 400 or 500 mg]) factorial arrangement of treatments in which three hundred and sixty broiler chickens at finisher stage were randomly allocated to twelve treatments with three replicates of ten birds each. Level of Hoodia gordonii meal supplementation had no effect (P>0.05) on diet intake, intake as percentage of live weight, growth rate, feed conversion ratio, live weight at 42 days of age and mortality of broiler chickens at finisher stage. All carcass characteristics were not affected (P>0.05) by the treatments except fat pads. Chickens given a daily dose of 300 mg of Hoodia gordonii meal had lower (P<0.05) fat pad weights than unsupplemented ones. Male broiler chickens had higher (P<0.05) feed intake and heavier drum sticks than female broiler chickens. Experiment 2 examined the effect of Hoodia gordonii meal dose interval at finisher stage in a 2 (two sexes of chickens) x 3 (dosage intervals) factorial, complete randomized design that involved three hundred and sixty chickens that were randomly allocated to six treatments with six replicates of ten birds each. Broiler chickens were fed either a grower diet without Hoodia gordonii meal; grower diet with 300 mg of Hoodia gordonii meal/ bird supplemented everyday for 12 days; or grower diet with 300 mg of Hoodia gordonii meal/ bird supplemented twice, on 30th and 36th days of age. Hoodia gordonii meal dose interval had no effect (P>0.05) on dry matter feed intake, intake as percentage of live weight, growth rate, live weight at 42 days of age, feed conversion ratio, mortality and all carcass characteristics except fat pad of broiler chickens. Daily dosing with 300 mg of Hoodia gordonii meal/ bird reduced (P<0.05) fat pad weights of broiler chickens by 18 percentage points. Male broiler chickens had higher (P<0.05) feed intake, nitrogen digestibility, nitrogen retention and live weight than female broiler chickens. It is concluded that chickens given a daily supplement of 300 mg of Hoodia gordonii meal had lower fat pad weights than unsupplemented ones. This could not be explained in terms of differences in feed intake, digestibility, or growth rate.
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36

Stringfellow, Kendre Duaron. "Evaluation of agricultural disinfectants and necrotic enteritis preventatives in broiler chickens." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3237.

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37

Waldenstedt, Lotta. "Coccidial and clostridial infections in broiler chickens : influence of diet composition /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1998. http://epsilon.slu.se/avh/1998/91-576-5536-7.gif.

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38

Ziaei, Nemat. "Optimisation of diet composition for phytase application strategies in broiler chickens." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505837.

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39

Koerhuis, Alphonsus Nicolaas Maria. "Quantitative genetic studies on growth and reproductive traits in broiler chickens." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/11003.

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This thesis considers three major quantitative genetic topics characteristic of growth and reproductive traits in broiler breeding, i.e. (1) the estimation of maternal effects in juvenile body weight (JBWT), (2) selection for food conversion into growth defined as a ratio (FCR), and (3) non-normality and curvilinearity of heritability of egg production distributions and the genetic relationships of those reproductive traits with juvenile growth. Restricted maximum likelihood (REML) methods based on the individual animal model were utilised in the estimation of variance components to make optimum use of the data and take account of selection. Estimates of the maternal additive genetic variation were small relative to the direct additive genetic variation of JBWT for two broiler populations investigated. The negative estimates of the direct-maternal genetic correlation (rAM) were unexpected and prompted the investigation of more appropriate and detailed statistical models taking account of direct-maternal environmental covariation, estimated either as the covariance between the environmental maternal and the environmental residual effects or as a maternal phenotypic effect through regression on the mother's phenotype. Whilst the goodness-of-fit of these alternative models was superior, the estimates of rAM were not much affected. The choice of the fixed effect structure was shown to be paramount in the estimation of maternal effects. Thus far, maternal effects were lumped together into a single component. Next, the results were described of an experiment conducted to identify individual pathways related to the egg causing maternal variation in JBWT and to establish their effect on offspring-parental regressions. Antagonistic maternal pathways of egg weight at the start and at the 18th day of incubation were observed. Their effects largely offset each other and hence biased the offspring-dam regression only slightly. A high loss in egg weight during incubation, indicative of poor egg shell quality, was identified as the likely cause for the negative estimates of rAM.
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40

Griffin, Jacqueline Reedy. "Growth and Development of Modern Commercial Broiler Chickens Under Nutritional Influences." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1503308489014284.

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41

Ross, Lauren S. "The effect of Woody Breast Disease on behavior in broiler chickens." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1565906339720286.

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42

Shields, Sara J. "Dustbathing by broiler chickens : characteristics, substrate preference, and implications for welfare /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.

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43

Cooper, Kerry Kevin. "Necrotic Enteritis in Broiler Chickens: Studies in Disease Reproduction and Pathogenesis." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/195545.

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Necrotic enteritis in poultry is caused by Clostridium perfringens type A, and is estimated to cost the worldwide poultry industry approximately $2 billion dollars a year, due to increased mortality and decreased feed conversion and weight gain. Very little is known about the pathogenesis of this disease due to the lack of a consistently reproducible experimental model. This dissertation outlines the development of an effective and consistent experimental model for necrotic enteritis in broiler chickens. It was also found that in vivo passage through the chicken's intestinal tract let to increased virulence; we increased the proportion of birds developing disease from 34.6% to 81.4%. Researchers have proposed that alpha toxin (CPA) is believed to be the critical virulence factor of the disease. All type A isolates have the potential to produce CPA, thus we challenged birds with numerous type A isolates that are virulent in other animal hosts. However, we found that they did not produce necrotic enteritis in broiler chickens. In addition, challenge with culture supernatant alone failed to produce gross lesions in the birds, although challenging with washed whole cell cultures did do so. Vaccinating birds with HIS-tagged recombinant CPA provided partial protection against disease; there was a 42.0% decrease in lesion development. The conclusion of this doctoral research is that CPA does have a role in the pathogenesis of necrotic enteritis in broiler chickens, but there are apparently other critical virulence factors involved in the development of disease.
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44

Iji, Paul Ade. "Natural development and dietary regulation of body and intestinal growth in broiler chickens." Title page, contents and summary only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phi25.pdf.

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Corrigenda inserted behind title page. Bibliography: leaves 275-306. The pattern of body growth and intestinal development of an Australian strain of broiler chicken, the Steggles x Ross (F1) in response to different diets was studied. Five experiments were designed to examine the pattern of growth and mechanisms involved. In four other experiments, the mechanisms underlying the gross response of the broiler chicks to dietary ingredients, anti-nutritive factors and growth enhancers were examined. Results indicated that a rapid development of the small intestine preceded significant overall body growth. Body growth would, however, depend more on the various physiological events such as those related to mucosal growth and renewal, digestive enzyme function, and nutrient transport. Some of the differences observed in productivity of broiler chickens on different diets were traced to events at the intestinal level.
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45

Abdel-Muttalab, Salah Ahmed. "Nutritional value of rapeseed and faba bean for poultry." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283076.

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46

Anderson, Mallory Grace. "Chicken or fish? Do environmental complexity and stocking density impact affective states of broiler chickens and rainbow trout?" Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/105133.

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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.
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47

Sebastian, Sylvester. "The effects of supplemental microbial phytase on nutrient utilization in broiler chickens." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0012/NQ30380.pdf.

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48

McLaren, Paul Edward. "The identification of factors causing low fertility and hatchability in broiler chickens /." Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09AB/09abm161.pdf.

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49

Sebastian, Sylvester. "The effects of supplemental microbial phytase on nutrient utilization in broiler chickens /." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34448.

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The influence of microbial phytase on growth performance, availability of macro and trace minerals, apparent ileal digestibility (AID) and apparent "fecal" digestibility (AFD) of amino acids (AA) and CP were investigated. The optimum level of dietary Ca and P for the maximum efficacy of supplemental phytase in broiler chickens was also studied. Phytase supplementation (600 U/kg) to a low P diet increased $(P 0.05)$ on feed efficiency in broiler chickens at 21 d. The efficacy of phytase, particularly in stimulating growth, was higher in male than female chickens. The relative retention of Ca, P, Cu, Zn and N increased by addition of phytase to a low P diet but phytase had no effect $(P >0.05)$ on the retention of Mg, Mn and Fe. Phytase supplementation increased $(P 0.05)$ on plasma Zn, Cu, and Mg. Phytase increased $(P 0.05)$ on mineral proportions in the tibia ash; however, it increased $(P 0.05)$ on AID of any of the AA in male chickens. Addition of phytase did not have any effect $(P > 0.05)$ on AFD of any of the AA in male chickens but increased $(P 0.05)$ on either AID or AFD of CP and AA at 21-d. In summary, phytase supplementation increased the growth performance, availability of P, Ca, Cu, Zn and N, plasma P, and tibia ash and reduced plasma Ca; it also increased the AID and AFD of most of the AA, particularly in female chickens at 28-d. The efficacy of microbial phytase was high when dietary P and Ca levels were low.
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50

Ibrir, Fathia. "The use of plant extracts as anticoccidial feed additives in broiler chickens." Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411151.

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