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Kumalo, Molefi Petrus. "Characterization of sheep and goat production systems amongst small-scale farmers in the Southern Free State." Thesis, Bloemfontein : Central University of Technology, Free State, 2014. http://hdl.handle.net/11462/266.
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Vos, Pieter Johannes Andreas. "The effect of supplementary light on the productive performmance of dorper lambs fed intensively." Thesis, Bloemfontein : Central University of Technology, Free State, 2010. http://hdl.handle.net/11462/25.
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Thesis (M. Tech.) - Central University of Technology, Free State, 2010The objective of this research study was to quantify the differences in average daily gain (ADG), back fat thickness (BFT), eye muscle area (EMA), fat thickness (FT) on different body parts, the feed conversion ratio (FCR) and body dimensions (by means of body measurements) of Dorper lambs exposed to supplemented light. For this study 120 Dorper lambs (115 ± 10 days old) weighing (29.76 ± 5.01kg) were used. The lambs were randomly divided into three homogeneous groups (20 castrated and 20 intact males). The three groups were then exposed to different levels of supplemented light at 145 lux (16h, 24h and normal photoperiod). The animals were fed ad libitum with pellets containing 9.5 MJ ME/kg DM and 12% CP in open pens. The animals were weighed every 7 days while ultrasound scanning of the EMA and the BFT was done at the beginning and the end of the 35 day trial. The ADG, FCR and feed intake (FI) were calculated at the end of the trial. Linear body measurements including shoulder height, body length and heart girth were taken at day 1 and day 35 respectively. All the animals were slaughtered at the end of the trail. The carcasses were then weighed, graded and the FT was measured with a caliper. The final results of the study showed that no significant differences between the three treatment groups (consisting of wethers and rams) in terms of body measurements, ultrasound scanning ADG and FCR could be detected. However, a significant difference was found between the wethers and the rams in the whole trial for ADG. The ADG of the rams exposed to 16 hours of supplemented light was significantly better than the normal photoperiod and the 24 hour light supplementation group.
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Tománek, Jiří. "Výroba součásti "Táhlo zadní"." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228385.
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The aim of this diploma thesis is to propose a production technology of a given part based on technological and economic factors. At first it is found, if the part is producible by fineblanking. The theoretical part of the diploma thesis is concerned with the description of the conventional sheet metal cutting theory, fineblanking theory and bending theory. In the practical part of the diploma thesis, four variants of cut-in plan are dealt with including the selection of the optimal one based on technological and economic calculations. It is the production of a PULL REAR iron made of the steel sheet 11 320.21, thickness of 3 mm and a production run of 75 000 pieces per year.
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Nääs, Julia, and Michaela Martinez. "Svensk ull i textilproduktion. : En studie om vilka för- och nackdelar svenska textilföretag stött på i produktion med svensk ull." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-23502.
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Majoriteten av den ull som produceras av svenska får har under flera år slängts eller bränts upp. Samtidigt importerar svenska textilföretag tonvis med ull för miljoner kronor varje år. Detta problem uppmärksammades för några år sedan och ett antal svenska företag har sedandess börjat producera produkter av den svenska ullen. I denna kvalitativa studie har en undersökning gjorts för att sammanställa för- och nackdelar med att producera textilprodukter i svensk ull. Semistrukturerade intervjuer har genomförts med tio olika företag som idag jobbar med materialet. Resultatet av studien visar att det största problemet med ullproduktion inom Sverige är bristen på en strukturerad infrastruktur inom inköp och produktion. Fördelar med att producera textila produkter i svensk ull är att det är ett materialmed goda egenskaper för flera användningsområden. Det är ett hållbart materialval då ullen annars går till spillo. Närheten till materialet underlättar även kontrollen över att helavärdekedjan sköts på ett etiskt och hållbart sätt.The majority of the wool produced by Swedish sheep has been discarded or burned for several years. At the same time, Swedish textile companies import tons of wool for millions of swedish crowns each year. This problem was brought to attention a few years ago and a number of Swedish companies have since started to produce products from the Swedish wool. In this qualitative study, an investigation was conducted to compile the pros and cons of producing textile products in Swedish wool. Semi-structured interviews have been conducted with ten different companies that are currently working with the material. The results of the study show that the biggest problem with wool production in Sweden is the lack of an organized infrastructure in purchasing and production. The advantage of producing textile products in Swedish wool is that it is a material with good properties for several applications. It is a sustainable choice of material as the wool is otherwise wasted. The proximity to the material also facilitates the control of the entire value chain being managed in an ethical and sustainable way.
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Muzikant, Miroslav. "Výroba součásti z plechu - "Vanečka"." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229404.
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The aim of this diploma thesis is processing the new technology of production single parts from metal plate „ Vanečka", which produced is yearly set 50000 pieces. Component of made in steel S235JRG1 (ČSN 41 1373) thickness 3 and 5 mm. Based on literary search rolling cutting and bending are designed two variants of production. Both variants use for cut - out cloak and face rolling cutting close - set on press LEN 63C. Different operation is bending. First variant includes bending in the bending tool, the other on press brake. Both variants is processed economics revaluation and consequently intended transition points.
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Glorieux, Emile. "Constructive cooperative coevolution for optimising interacting production stations." Licentiate thesis, Högskolan Väst, Avd för automationssystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-7685.
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Engineering problems have characteristics such as a large number of variables, non-linear, computationally expensive, complex and black-box (i.e. unknown internal structure). These characteristics prompt difficulties for existing optimisation techniques. A consequence of this is that the required optimisation time rapidly increases beyond what is practical. There is a needfor dedicated techniques to exploit the power of mathematical optimisation tosolve engineering problems. The objective of this thesis is to investigate thisneed within the field of automation, specifically for control optimisation ofautomated systems.The thesis proposes an optimisation algorithm for optimising the controlof automated interacting production stations (i.e. independent stations thatinteract by for example material handling robots). The objective of the optimisation is to increase the production rate of such systems. The non-separable nature of these problems due to the interactions, makes them hard to optimise.The proposed algorithm is called the Constructive Cooperative CoevolutionAlgorithm (C3). The thesis presents the experimental evaluation of C3, bothon theoretical and real-world problems. For the theoretical problems, C3 istested on a set of standard benchmark functions. The performance, robustness and convergence speed of C3 is compared with the algorithms. This shows that C3 is a competitive optimisation algorithm for large-scale non-separable problems.C3 is also evaluated on real-world industrial problems, concerning thecontrol of interacting production stations, and compared with other optimisation algorithms on these problems. This shows that C3 is very well-suited for these problems. The importance of considering the energy consumption and equipment wear, next to the production rate, in the objective function is also investigated. This shows that it is crucial that these are considered to optimise the overall performance of interacting production stations.
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Chadwick, Megan. "Fetal programming of sheep for production on saltbush." University of Western Australia. School of Animal Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0033.
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[Truncated abstract] Saltbush is one of the few types of forage that will grow on salt affected land but, sheep struggle to maintain weight when grazing saltbush mainly because of its high salt content. Therefore, a strategy to improve salt tolerance of sheep would be beneficial to the profitable use of revegetated saline land. This could be done by manipulating the dietary salt load of pregnant or lactating ewes which could 'program', or permanently alter the physiology of their offspring to allow them to cope better with a high-salt diet as adults. When rat dams consume a high amount of salt during pregnancy, the salt balance mechanisms of their offspring are 'programmed' due to suppression of the offspring's renin-angiotensin system in early development. If this occurs in offspring from ewes grazing saltbush, beneficial adaptations may be programmed in these offspring which could allow them to better cope with the high-salt content of saltbush. I tested the general hypothesis that offspring born to ewes that consumed a high-salt or saltbush diet from mid-pregnancy to early lactation would have an increased capacity to cope with salt that would allow them gain weight when grazing saltbush in later life. To test this hypothesis, I pair-fed ewes either a high-salt diet (14% NaCl) or control diet (2% NaCl) in an animal house from day 60 of gestation until day 21 of lactation. During the same period, I also conducted a field experiment where ewes grazed on saltbush (supplemented with barley) or on pasture (supplemented with lupins). ... This led to the high-salt offspring retaining more salt than control animals. In contrast, the renin activity of saltbush was consistently lower than pasture offspring which allowed them to excrete salt more rapidly. In experiment three, the saltbush offspring gained tissue weight after grazing saltbush for 8 weeks, whereas the offspring in the other three treatments lost weight. High-salt and saltbush offspring also had higher greasy fleece weights at 22 months of age than their respective control groups. Feeding saltbush to ewes from mid-pregnancy to early lactation induces physiological adaptations in their offspring that allow them to cope better with salt and gain weight when grazing saltbush as adults, supporting my hypothesis. However, contrary to expectations, the high-salt offspring did not gain weight when grazing saltbush because their physiological adaptations, such as salt retention, did not allow them to cope better with a salt load. The reason that saltbush offspring showed different adaptations to highsalt offspring is likely to be because saltbush contains not only NaCl but also high amounts of other minerals such as potassium, and other plant compounds, which may influence the adaptive responses of the offspring. This research has direct implications for farmers because it shows they could utilize otherwise unproductive saltland by grazing pregnant ewes on saltbush to 'program' their offspring to gain weight when they graze saltbush later in life.
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Fannon-Osborne, Amy Gail. "Hair Sheep Production in Temperate, Deciduous Appalachian Silvopastures." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/76825.
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Silvopastoral management has potential to diversify and increase the output from livestock production systems. Silvopasture production offers solutions to many management issues associated with grazing systems in the Appalachian region. Several tree species have been proposed for silvopastures in humid temperate regions, but little data comparing animal performance from systems with different deciduous tree species are available. Forage and animal performance was compared from open systems (i.e., no trees) with that from silvopastures containing 13-yr-old honeylocust (Gleditsia triacanthos) or black walnut (Juglans nigra) trees. Cool-season grass-legume pastures were rotationally stocked with hair sheep crosses from mid-June through September. The objective of this project was to determine carcass characteristics and meat quality of hair sheep crosses grazing honey locust or black walnut silvopastures in comparison with traditional pasture systems.
Forage production varied by year with black walnut having lower production, especially in the 2009 season with black walnut producing less forage compared to open pastures and honeylocust silvopastures (P=0.0008). Only small differences in forage nutritive value were observed. Total gains and average daily gains (ADG) did not differ by treatment in 2008, but during the 2009 season black walnut silvopastures produced half the total gains (P=0.0427) and ADG (P=0.0513) of open pastures and honeylocust silvopastures.
Carcass characteristics evaluated did not vary among treatments except hot carcass weight with black walnut having lower weights (P=.0045). Meat quality characteristics did not vary among treatments (P>0.1). Shear force and fat content showed great differences and varied by year (P<0.05). Overall, carcass and meat quality was similar for all treatments showing great promise for silvopastures.Master of Science
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Campbell, Angus John Dugald. "The effect of time of shearing on wool production and management of a spring-lambing merino flock /." Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/00003254.
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Saatchi, Mustafa. "Genetic parameters of production traits in Welsh mountain sheep." Thesis, Bangor University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263274.
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Rorrer, Rebecca Kathleen. "Veterinary Therapeutic and Biologic Agents in Virginia Sheep Production." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34574.
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Biological and therapeutic agents are used in food animal production to maintain animal health and well being, prevent and treat disease, and to maintain or enhance production. Concerns about the use of pharmaceutical agents in food animal production have been raised, especially in relation to food quality and safety. This study addressed the scarcity of information concerning the quantity of pharmaceuticals being used and the reasons for their use in sheep production. Additional goals included determining the sources of information used by shepherds in making treatment decisions and evaluating the economic impact that pharmaceutical usage has on sheep production. Thirty-nine Virginia sheep producers participated in this study of four months duration from March through September. After completing an initial questionnaire to determine flock and management characteristics, participants were asked to record all treatments with biological and therapeutic agents that occurred within their sheep flocks. A total of 14,310 treatments were recorded for a median of 1.5 treatments per sheep per month. Parasite control and vaccination were the most frequent reasons for treatment (64.9% and 15.2%, respectively) with vitamin/mineral supplementation being the next most common (8.8%). Price information was collected for 13,912 treatment events. An estimated total of $7,523.78 was spent on pharmaceutical treatment over the course of the study. This amounts to a cost of $0.63 per sheep per month of observation. Results of this study will enhance the ability of producers to evaluate treatment decisions, allow comparisons to be made between operations and provide a base of information for future research.Master of Science
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Moss, Angela R. "The effect of diet composition on methane production by sheep." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243640.
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Stevenson, Anne Graham. "Some effects of trichostrongylidosis on metabolism and production of sheep." Thesis, University of Glasgow, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292577.
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Ward, Samantha. "The welfare and production implications of fostering methods in sheep." Thesis, University of Northampton, 2013. http://nectar.northampton.ac.uk/7050/.
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Fostering is a method used by shepherds that allows the successful rearing of abandoned lambs onto other ewes, or the ability to provide surplus lambs a new mother in the case of triplets. Past research has focused on the success rates of the varying methods available, however, more research is needed to increase the knowledge about commonly selected fostering methods and the behaviour, welfare and production implications of the different methods used. Questionnaires were distributed at national farming events targeting registered sheep farms around the UK to establish which foster methods were currently in use and to collate the farmers opinions of their usage in modern day sheep farming. An experimental study was carried out to assess the welfare and production implications of the use of these methods. 84 ewes were allocated to one of the three experimental foster methods or the control group (twin lambing). They were also classified according to their lambing experience (multiparous or primiparous). Behavioural observations were conducted post-foster on the ewes and their lambs. The ewes’ salivary cortisol concentration and heart rate frequency were also monitored at 0, 30, 60, 90 and 180 minutes post-foster. To assess the production implications of the different foster methods, lamb weights and body measurements were taken at 0, 7, 30, 90 and 180 days of age to asses growth rates. Lambs were weaned at 3 months of age and remained at pasture until slaughter, at approximately 6 months of age. The lambs’ carcass quality was assessed by means of weights, zoometric measurements and conformation scores and some meat quality parameters (ultimate pH, water holding capacity and colour) were also investigated. 93% of farmers used fostering, preferring to foster rather than artificially rear lambs. Almost two-thirds favoured birth fluids (64%) and 19% of farmers used restraint crates, The most popular combination of foster methods was cervical stimulation plus birth fluids (CSBF). Exploratory factor analysis showed two main components helping farmers to decide which foster method to use, the ewes’ health and welfare and the farmers previous knowledge and success of a foster method. Birth fluids, restraint and CSBF were methods selected for behavioural data, showing that negative behaviours were significantly higher for restrained ewes compared to other treatments. Restrained ewes also showed significantly higher heart rates and salivary cortisol concentrations. Production data showed that ewe reared lambs gained significantly more weight than artificially reared lambs up to 90 days of age. However, there was no difference from that time until slaughter. Conformation and chest roundness scores were significantly better for ewe reared lambs compared to artificially reared ones. Foster methods did not have any significant effect on the growth rates, carcass or meat quality measurements for the lambs studied. The majority of farmers selected to use birth fluids, seen as a welfare friendly and less-invasive method of fostering. However, some farmers selected the restraint method based on the urgency of the lambs to receive milk and to avoid artificial rearing. The restraint crates caused significant changes to the ewes’ behaviour and increased their heart rates and cortisol concentrations, indicating a higher level of distress that could be compromising the ewes welfare. Lamb growth rates, carcass and meat quality were not affected by the different foster methods, proved that successfully established foster methods of any kind have no differential implications for the farms productivity (under UK commercial practices). Artificially reared lambs did show worse carcass conformation, suggesting that ewe rearing, and therefore fostering, offers advantages for the productivity of sheep farmers.
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Weaver, Andrew Ryan. "Evaluation of terminal sire breeds for hair sheep production systems." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/80300.
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Terminal sire crossbreeding systems which improve growth performance while maintaining parasite resistance have the potential to enhance the profitability of hair sheep enterprises. Katahdin (KT, n = 4), Suffolk (SU, n = 3), and Texel (TX, n = 3) rams were randomly mated to KT ewes over two years (Y1, Y2) at the Virginia Tech Southwest Agricultural Research and Extension Center. Post-lambing until weaning (80 d), pairs were managed on fescue pasture. At weaning, lambs (n = 192) were moved to an ungrazed pasture and provided a concentrate pellet daily for a 90 d grazing trial. During this time, BW, strongylid egg count (FEC), FAMACHA score and packed cell volume (PCV) were collected every 14 d. FAMACHA score - 3 was utilized as the basis for anthelmintic treatment. Post-grazing, lambs were fed to approximately 50 kg BW. Lambs were harvested at the Virginia Tech Meat Center and carcass evaluation performed 1 d post-harvest. Statistical analyses were conducted using SAS (SAS Institute Inc., Cary, NC) with Proc MIXED for repeated measures analysis and Proc GLM with Tukey?s test for mean separation. No differences existed between sire breeds for adjusted number of lambs born or number of lambs weaned. Adjusted birth BW was greater for SU-sired lambs than KT-sired and TX-sired (P < 0.05) in Y2. Adjusted weaning BW was smallest for KT-sired lambs compared to SU- and TX-sired lambs (P < 0.05) in both years. During the grazing trials, BW, ADG, lnFEC, FAMACHA and PCV varied over time (P < 0.001) with lower FAMACHA scores for KT-sired lambs than SU- and TX-sired lambs in Y1 (P < 0.05). A greater proportion of SU-sired lambs tended to require deworming than KT-sired lambs (P = 0.08). Adjusted BW post weaning was greater for TX-sired lambs than KT-sired lambs (P < 0.05) in Y1. Post-grazing, BW and ADG varied over time (P < 0.01) with no sire breed differences for ADG. At harvest, SU-sired lambs were heavier than KT-sired lambs (P < 0.05). TX-sired lambs had greater LM area than KT-sired lambs (P = 0.05). KT-sired lambs had the smallest leg scores (P < 0.05). These results indicate the potential of terminal sires (SU- and TX-sires) to improve lamb growth and carcass merit. TX-sired lambs had more similar parasite resistance characteristics to KT-sired Iambs and may have potential as terminal sires in forage based hair sheep production systems.Master of Science
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Sweeny, Joshua. "Associations between worm egg count and production in Dorper sheep." Thesis, Sweeny, Joshua (2008) Associations between worm egg count and production in Dorper sheep. Honours thesis, Murdoch University, 2008. https://researchrepository.murdoch.edu.au/id/eprint/13509/.
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With changes to the Australian sheep industry, breeds that have a meat emphasis are becoming increasingly adopted by farmers. One such breed is the Dorper sheep, which was used in this study to investigate the relationship between worm egg count and production attributes. Gastrointestinal worm burden was measured by worm egg counts (WECs) and production attributes that were examined included liveweight, body condition score (BCS), c-site fat depth and eye muscle depth. Two flocks of Dorper lambs (two-hundred and eighty nine Dorper ewe lambs, and two-hundred and thirty four entire Dorper ram lambs), were weaned onto two separate paddocks for grazing and natural worm challenge on a Kojonup property. At post weaning (approximately 10 months of age), each flock had their production attributes measured, along with individual WECs. Each flock was drenched at weaning and not drenched again until after individual WECs were measured. The measured flock WEC frequency distribution reinforced the concept that high flock WECs are influenced by a small percentage of the sheep within the flock and that Dorper sheep are similar to other breeds with respect to parasite population dynamics.
The relationships found between WEC and production attributes of both liveweight and eye muscle depth were positive, contradicting the hypothesis of that a negative relationship exists between WEC and production in the Dorper. Although this relationship between WEC and liveweight was weak and unexpected, the relationship was still significant (P<0.05). With an increasing WEC, BCS fell by 56.6% and 37.7% of average ram BCSs in twin and single born rams respectively (P<0.05), while an 18.6% decrease of average ewe BCS was observed in twin born ewes (P<0.05). The drop in body condition score and c-site fat depth may have contributed to overall leaner and lighter carcases (particularly in the ram flock). Given that the liveweights were actually higher in these same animals, this suggests a reduced dressing percentage due to increased non-carcase components, possibly gastrointestinal tissue mass.
With increasing WEC the association of liveweight increase and BCS decline indicated that sheep with a higher worm burden may have heavier intestines, when compared to sheep with a low worm challenge. By using liveweight change to assess GIN impact on productivity, production losses linked to gastrointestinal parasite infection may be underestimated. Instead of using liveweight change in assessing the effect of a worm challenge, measurements of the carcass yield may be a more reliable measure in revealing the real economic impact of gastrointestinal worms on sheep meat production systems.
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Rude, Mark Edward. "Estimating spotted knapweed intake of sheep using NIRS technology." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/rude/RudeM0810.pdf.
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Targeted grazing is proving to be effective in controling spotted knapweed infestations. Maximizing the potential of targeted grazing requires a method to determine the botanical composition of individual diets of grazing animals over time Fecal near infrared reflectance spectroscopy (NIRS) has been used to estimate the botanical composition of sheep consuming, leafy spurge, mountain big sage brush, and juniper, but has not been used to estimate dietary composition of sheep consuming spotted knapweed. Fecal NIRS spectra collected from three feeding trials were used to develop modified partial least squares regression equations to predict percent spotted knapweed in sheep diets. Independent validation of individualy developed equations resulted in R² values of .22 - .72. An equation developed by combining data from all three trials resulted in acceptable levels of precision (R²= .96) and was used to analyze data collected from range fecal sampling trials conducted in 2006. Two fecal sampling trials were conducted in 2006 to determine NIR's ability to detect differences in dietary composition of sheep grazing spotted knapweed infested range over time. Approximately 90 fecal samples were collected on July 13 and again on August 15 from a band of 900 ewes grazing spotted knapweed infested range to determine changes in diet over time. Fecal samples from five randomly selected ewes in the same band were collected weekly (June 22 - August 17) to detect variation in indiviudal intake over time On July 13, 55% of ewes from had 0-5% spotted knapweed in their diets while 44% had 5-20% spotted knapweed in their diets. On August 15, 1% of ewes, had <10% spotted knapweed in their diets and 44% had 20-25% spotted knapweed in their diets. With the exception of July 6, individual intake of spotted knapweed was similar (P > .05) from June 22, through July 20, but was greater (P > .05)from July 27 through August 17 than from June 22 through July 20. These results suggest that the appropriate time to apply grazing for spotted knapweed control is later in the growing season when sheep are including more of the target plant in their diet.
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Tadros, Kamal I. "Effects of Grazing Intensity by Sheep on the Production of Atiplex nummularia and Sheep Live Weight in Jordan." DigitalCommons@USU, 1987. https://digitalcommons.usu.edu/etd/3585.
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Rangelands in Jordan are deteriorated due to a combination of harsh environmental conditions and human misuse. Jordan is importing increasingly large quantities of meat and animal products to meet the demand from its growing population. Sheep are supplementaQ ly fed during the dry season and large quantities of grain supplements are imported every year.
Significant success has been attained in the establishment of Atriplex nummularia lindl. (ATNU) in Jordan. There is, however, a general lack of adequate research to determine if ATNU is effectively utilized by local sheep, to what extent it is utilized and to what extent it tolerates grazing. The objectives of this research were to determine the effects of grazing ATNU at two intensities (moderate and heavy) on subsequent production of ATNU browse, and on sheep live weight.
Results of this research showed that HNU shrubs are grazing tolerant, they are stimulated by grazing to produce more forage than the non-grazed shrubs. When heavily grazed in the fall, they showed greater compensatory growth than moderately grazed shrubs, but the moderately grazed shrubs gave sustained production better than those heavily grazed in both good and bad years.
Sheep grazing ATNU shrubs with native forage (grasses and forbs) in the fall gained more weight at the moderately grazed treatments. The amount of sheep-live-weight gain was positively affected by the amount of food intake per sheep metabolic body weight and inversely affected by the percentage of ATNU browse in the diet. ATNU although less preferred by sheep than grasses and forbs, could probably be used up to 40% of the diet and still maintain sheep live weight.
ATNU is a good source of forage especially during the dry season, it provides (with native grasses and forbs) a high-quality forage and may considerably reduce the amount of costly supplements imported to Jordan.
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Tuke, Amanda. "Grass production and sheep grazing on the island of Hirta, Scotland." Thesis, Imperial College London, 2001. http://hdl.handle.net/10044/1/11938.
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Beard, Andrew J. "Regulation of pituitary gonadotrophin production by inhibin in cattle and sheep." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277110.
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Luo, Qiu Jiang. "IGF-1 production by primary cultured hepatocytes from rats and sheep." Thesis, University of Aberdeen, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314610.
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Methods were established for the serum-free primary culture of rat and sheep hepatocytes. These were used to study the IGF-1 production by the cells. IGF-1 in media was separated by acid gel filtration or HPLC prior to RIA. IGF-1 production by both rat and sheep hepatocytes were time-dependent over 30 hours of culture. Production rates by rat cells in modified Eagle's medium, sheep cells modified Eagle's medium and Waymouth's medium were 13.1, 4.4 and 6.4 pmol/mg cell DNA/10 hours respectively. IGF-1 production by rat cells was very sensitive to altering concentrations of amino acids, glucose and both in the medium. IGF-1 production by sheep cells was also controlled by nutrients in modified Eagle's medium, but was not as sensitive as in rat cells. Growth hormone (GH), unlike insulin and T3, had no effect on hepatic IGF-1 production in rat cells. In contrast, omitting GH from the medium for sheep cells decreased IGF-1 production by 20-60% in sheep cells. Insulin also controlled hepatic IGF-1 production in sheep. The results show the species difference in the hepatice IGF-1 production and control between rats and sheep. Data in this thesis are thought to provide the first published evidence of a direct nutritional control over IGF-1 production in rat hepatocytes and to give the first direct evidence that sheep hepatocytes produce IGF-1 and this is directly controlled by GH.
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Sart, Sarula. "Temperament and milk quality in sheep and cattle." University of Western Australia. School of Animal Biology, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0030.
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[Truncated abstract] It is well known that cows produce more milk if they are comfortable at milking, because stress from milking may cause them milk ejection problems. Temperament is an intrinsic characteristic of the animals so may affect the level of comfort at milking, and stress from the milking process itself may have a greater impact on animals with nervous temperament than on those of nervous temperament. When the milking becomes a stressor, it may affect secretion of milk ejection hormones that, in turn, may affect milk yield and composition. There is little evidence for how animal temperament affects milk quality in different farm animals. In this thesis, I have examined the effects of temperament on quantity and quality of the milk from Merino ewes and Holstein cows. I also tested whether temperament affected the processing performance (clotting properties) of the milk from Merino ewes. The general hypotheses tested were: 1. Calm ewes would produce more milk of better quality than nervous ewes, and, consequently, the clotting properties would be better in the milk from calm ewes than from nervous ewes. 2. Calm cows would produce more milk of better quality than nervous cows.
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Cameron, Neil Donald. "Genetic improvement of lean meat production in terminal sire breeds of sheep." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/12147.
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Jin, Songqing. "Production technology and technology production : the economics of crop breeding in China /." 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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Claasen, Claasen. "The effect of agricultural production system on the meat quality of Dorper lambs." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/19896.
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Thesis (MScAgric)--Stellenbosch University, 2008.ENGLISH ABSTRACT: The aim of this study was to investigate the effect of South African production system (feedlot {FL-} or free-range {FR-}) and gender (ewes, rams or castrates) on growth and carcass characteristics of Dorper sheep. Male lambs (castrates and rams) grew twice as fast as ewes (P<0.05) under FL-conditions while much smaller differences were observed between gender groups in FR-lambs. FL-lambs produced heavier carcasses (P=0.0003) with higher dressing percentages (P<0.05) and greater carcass fatness levels (P<0.052) than FR- lambs. No differences attributable to production system were found on meat tenderness (as indicated by Warner Bratzler shear force strength) and on the intramuscular lipid concentration. In contrast, sensory evaluation results suggested that meat from FL-lambs was juicier and more tender than meat from FR-lambs. The sensory panel could not distinguish between FL and FR meat as far as the attributes of aroma and flavour were concerned. Cholesterol results indicated that for intermuscular fat, higher cholesterol levels were observed for FL-lambs than for FR-lambs. The level of palmitic acid (C16:0) was significantly higher (P=0.0375) in the Longissimus dorsi (LD) muscles of FL-lambs. For intramuscular fat from the Biceps femoris (BF) muscle, g-linolenic acid (C18:3n-6) was higher (P<0.0001) in FL- lambs. Results for intramuscular BF further indicated that ram lambs had the highest (P=0.0019) palmitic acid (C16:0) and sum of TUFA (P=0.0014), castrates had the highest (P=0.0260) α-linolenic acid (C18:3n-3) and g-linolenic acid (C18:3n-6), while ewe lambs had the highest (P=0.0014) SFA concentrations. Linoleic acid (C18:2n-6c) was significantly higher (P=0.0067) in the subcutaneous fat of FL-lambs while FR-lambs had more linolenic acid (C18:3n-3). For the kidney fat, FR-feeding increased (P < 0.05) stearic (C18:0), linolelaidic (C18:2n-6t), α-linolenic (C18:3n-3) and homo-g-linolenic acid (C20:3n-6) percentages. Conversely, linoleic acid (C18:2n-6c) was increased (P=0.0372) by FL-feeding. For the intermuscular fat, FR-lambs had higher linolenic acid (C18:3n-3) and SFA (P=0.0113 and P=0.0341) compared to FL-lambs. On the other hand, the sum of TUFA for the intermuscular fat was higher (P=0.0341) in FL-lambs compared to FR-lambs. Results from the study imply that the consumer may not necessarily be able to discern between meat from FR- or FL-lambs, although they may possibly discriminate against the increase in visible fatness of FL-lambs. No clear advantage of production system in terms of human health could be demonstrated as far as the proximate chemical composition and the fatty acid composition of the meat was concerned. The faster growth and the associated shorter production cycle of FL-lambs could be an advantage under certain production systems. However, it needs to be weighed against the cost of concentrate feeding and the preference consumers are likely to develop for lamb produced in natural environments.
AFRIKAANSE OPSOMMING: Die doel van die studie was om Suid Afrikaanse produksiestelsel (voerkraal {VK-} of veld {VD}) en geslag (ooie, hamels of ramme) op die groeivermoë en karkaseienskappe van die Dorperskape te bepaal. Manlike lammers (ramme and hamels) het twee keer vinniger (P<0.05) as ooilammers onder VK-toestande gegroei, terwyl kleiner verskille tussen geslagsgroepe by VD-diere waargeneem is. VK-lammers het swaarder karkasse (P=0.0003), hoër uitslagpersentasies (P<0.05) en meer karkas vet (P<0.052) as VD -lammers vertoon. Geen verskille as gevolg van produksiestelsel is op die sagtheid van vleis (soos aangedui deur Warner-Bratzler skeurkragwaardes) en die binnespierse vetinhoud gevind nie. Daarenteen het sensoriese analises aangedui dat vleis van VK-lammers sappiger en sagter as vleis van VD- lammers was. Die sensoriese paneel kon nie verskille aangaande die aroma en geur van vleis tussen VK- en VD-vleis onderskei nie. Cholesterolvlakke was hoër vir VK-lammers as by VD-lammers. Die vlak van palmitiese suur (C16:0) was hoër (P=0.0375) in die Longissimus dorsi (LD) spier van VK-lammers. Vir binnespierse vet van die Biceps femoris (BF) spier was g-linoleniese suur (C18:3n-6) hoër (P<0.0001) in VK-lammers. Resultate vir binnespierse vet van die BF spier het verder bewys dat ramlammers die hoogste (P=0.0019) palmitiese suur (C16:0) and totale onversadigde vetsure (P = 0.0014) getoon het, hamels die hoogste (P=0.0260) α-linoleniese suur (C18:3n-3) en g-linolenese suur (C18:3n-6) getoon het terwyl ooilammers die hoogste (P=0.0014) versadigde vetsuurvlakke getoon het. Linoliese suur (C18:2n-6c) was hoër (P=0.0067) in die onderhuidse vet van VK-lammers terwyl VD-lammers meer linoliese suur (C18:3n-3) gehad het. Resultate vir niervet het getoon dat VD-voeding die persentasies van steariese (C18:0), linoleladiese (C18:2n-6t), α-linoleniese (C18:3n-3) and homo-g-linoleniese suur (C20:3n-6) verhoog (P<0.05) het relatief tot VK-voeding. Linoliese suur (C18:2n-6c) is deur VK-voeding verhoog (P=0.0372). Vir intermuskulêre vet het VD-lammers hoër linoleniese suur (C18:3n-3) en versadigde vetsure (P=0.0113 en P=0.0341) as VK-lammers gehad. Die totale onversadigde vetsure vir tussenspiere vet was hoër (P=0.0341) in VK-lammers in vergelyking met VD-lammers. Resultate van hierdie studie dui daarop dat verbruikers nie noodwendig tussen vleis van VD- en VK-lammers sal onderskei nie, alhoewel hulle dalk teen die sigbaar vetter vleis van VK-lammers kan diskrimineer. Geen definitiewe voordeel in terme van menslike gesondheid kon op grond van die chemiese samestelling van die vleis bevestig word nie. Vinniger groei van VK-lammers, en die korter produksiesiklus wat daarmee verband hou, mag onder sekere produksie stelsels ʼn voordeel wees. Die voordeel moet teen die hoër koste van VK-voeding en die voorkeur van verbruikers vir lam produksie in natuurlike omgewing opgeweeg word.
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Gulbenkian, Marcos. "The potentials for improvement of traditional sheep cheese production systems in Portugal." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333431.
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Neto, Jaime Martins de Sousa. "Characterization of sheep and goat farming production systems in the brazilian northeasth." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16345.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoThe research aims to characterize this the creation of small ruminants in northeastern Brazil. To this end, initially we aimed to analyze the importance of cluster analysis for characterization of small ruminant production systems, using as a methodological tool to literature. Thus, it was observed that the cluster analysis methodology to characterize the animal production systems, is a technique used worldwide to identify the successful cases, advantageous aspects and obstacles in order to support programs that facilitate the leverage of farming. Subsequently, based on data collected from field research through interviews with 224 farmers in four northeastern states, it used the cluster analysis technique called cluster analysis, aimed specifically identify the homogeneous groups and check leveraging factors and restrictors groups in relation to the general characteristics of the producer and his property, the composition of herds, the socioeconomic aspects of producer and practices related to reproductive management, food and health. Thus, five homogeneous groups have been identified (or clusters) of small ruminant producers in northeastern Brazil. Group I represents 25% of the producers examined, where farms have little area, however, high stocking density, highlighting the presence of cattle more quantitative in that group, characterized as "small farms focused on milk production ". Group II contains 20% of analyzed producers, with the quantitative smaller herds among the groups, lower adoption of management practices and a higher frequency of exclusive breeders of goats and sheep, being defined as "small flocks not technified". Group III is the largest group, comprising 28% of respondents creators, where the goat herd significantly exceeds the sheep flock, being named as "traditional goat farmers". Group IV absorbs 16% of the most experienced producers, with the largest areas of observed properties, showing also a larger quantity of animals and a higher percentage of adoption of management practices, which are defined as "large farms technicality". Group V covers 11% of the youngest producers, the lowest group analyzed where mixed farms of sheep, goats and cattle are most frequent, representing 33% of producers in that group, named "emerging mixed farms." There was generally an increase in all groups regarding the feeding management used by Northeastern producers caused by the promotion of the development of the rural sector policies. They identified some obstacles to be overcome, especially with regard to reproductive health and herd management.
A pesquisa realizada neste pretendeu caracterizar a criaÃÃo de pequenos ruminantes na RegiÃo Nordeste do Brasil. Para tanto, inicialmente, teve como objetivo analisar a importÃncia da anÃlise de clusters para caracterizaÃÃo de sistemas de produÃÃo de pequenos ruminantes, utilizando-se como ferramenta metodolÃgica a pesquisa bibliogrÃfica. Dessa forma, observou- se que a metodologia de anÃlise de clusters, visando à caracterizaÃÃo dos sistemas de produÃÃo animal, à uma tÃcnica utilizada no mundo todo, visando identificar os casos exitosos, aspectos vantajosos e impedimentos, de forma a subsidiar aÃÃes que propiciem a alavancagem da atividade agropecuÃria. Posteriormente, a partir de dados coletados de uma pesquisa de campo, por meio de entrevistas com 224 produtores de quatro estados nordestinos, utilizou-se a tÃcnica de anÃlise de agrupamento denominada de anÃlise de clusters, visando, especificamente, identificar os grupos homogÃneos existentes e verificar os fatores alavancadores e restritores dos grupos em relaÃÃo Ãs caracterÃsticas gerais do produtor e de sua propriedade, à composiÃÃo dos rebanhos, aos aspectos socioeconÃmicos dos produtores e Ãs prÃticas relativas ao manejo reprodutivo, alimentar e sanitÃrio. Dessa forma, foram identificados cinco grupos homogÃneos (ou clusters) de produtores de pequenos ruminantes na RegiÃo Nordeste do Brasil. O grupo I representa 25% dos produtores analisados, onde as fazendas tÃm pouca Ãrea, no entanto, elevada densidade animal, destacando-se a presenÃa do rebanho bovino com maior quantitativo nesse agrupamento, caracterizando-se como âpequenas fazendas centradas na produÃÃo de leiteâ. O grupo II contÃm 20% dos produtores analisados, apresentando os menores quantitativos de rebanhos dentre os grupos, menor adoÃÃo de prÃticas de manejo e a maior frequÃncia de criatÃrios exclusivos de caprinos e ovinos, sendo definido como âpequenos rebanhos nÃo tecnificadosâ. O grupo III à o maior grupo, contendo 28% dos criadores entrevistados, onde o rebanho caprino supera sensivelmente o rebanho ovino, sendo nomeado como âcaprinocultores tradicionaisâ. O grupo IV absorve 16% dos produtores mais experientes, com as maiores Ãreas de propriedades observadas, apresentando, tambÃm, um maior quantitativo de animais e um maior percentual de adoÃÃo de prÃticas de manejo, sendo definidos como âgrandes fazendas tecnificadasâ. O grupo V abrange 11% dos produtores mais jovens, sendo o menor grupo analisado, onde os criatÃrios mistos de ovinos, caprinos e bovinos sÃo de maior frequÃncia, representando 33% dos produtores desse grupo, nomeado de âcriatÃrios mistos emergentesâ. Verificou-se, em geral, uma evoluÃÃo em todos os grupos no tocante ao manejo alimentar utilizado pelos produtores nordestinos, provocada por polÃticas de promoÃÃo do desenvolvimento do setor rural. Identificaram-se alguns entraves a serem superados, em especial no tocante ao manejo reprodutivo e sanitÃrio dos rebanhos.
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Seymour, Deborah. "The Antibody Production by Swine in Response to Sheep Red Blood Cells." TopSCHOLAR®, 1985. https://digitalcommons.wku.edu/theses/2847.
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Two experiments were conducted to study the antibody response of pigs challenged with the general antigen sheep red blood cells (SRBC).
In one experiment SRBC's were injected at one of four sties: intramuscularly into the neck, intramuscularly into the ham, subcutaneously into the fore flank or rear flank. These treatments were repeated four weeks later. The antibody responses to the four treatments were determined by microtiter and analyzed statistically. No significant (P> 0. 10) differences were found among responses to the four treatments during the fourth and eighth weeks after injections, but a significant (P<0.05) difference was found during the fifth week among all four groups. Coefficients of correlation showed highly significant (P<.0.01) relationships between SRBC antibody titer during the fourth week after injections and increase in weight of test animals from the beginning of the study until slaughter.
In a second experiment pigs were given intramuscularly either 2 milliliters of a 5% or 4 milliliters of a 10% SRBC suspension to determine the optimum dosage level. The difference between the antibody responses to these two treatments was not significant (P)0.10).
Results of this study indicate that when challenging hogs with SRBC, any of the commonly used sites for injection is acceptable. The injection of 2 milliliters of a 5% SRBC suspension is sufficient to obtain antibody titers which differentiate among individuals. Coefficients of correlation indicate a relationship may exist between SRBC antibody titer and some economically important traits.
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Midwood, Andrew J. "Application of the doubly labelled water technique for measuring CO2 production in sheep." Thesis, University of Aberdeen, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277286.
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The doubly labelled water technique (DLW) allows the estimation of the carbon dioxide production (rco2) of a free-living animal from which, with knowledge of the respiratory quotient (RQ), energy expenditure may be predicted. The aim of this project was to assess the performance of this technique in ruminant animals using sheep as a model. In a series of preliminary experiments physiological processes which may affect this technique were examined. It was found the administered isotopes equilibrated throughout the body water after 6 hours following either an oral or intravenous dosing. 2H lost in the form of methane was estimated to lead to errors in rco2 of between -3.27 and -6.54% and may be corrected for by use of a methane to urine enrichment ratio of 0.6536. Losses of 2H in exchangeable sites in faeces were estimated to lead to errors in rco2 of between -5.35 to -6.54%, again corrections factors were proposed. Sequestration of 2H into carcase fat was also quantified, a maximum error of 0.67% was estimated on rco2, although more 2H was detected in the fat free carcase this was assumed to be exchangeable 2H. A maximum error of -2.39% on water turnover (rH20) was estimated to arise from the recycling of 2H due to the catabolism of labelled body solids, although this was probably an overestimate. No convincing evidence was found to suggest the fractionation factors applied to human subjects are not equally applicable to ruminant animals. The baseline body water enrichment was altered by a change in diet from synthetic concentrates to fresh chopped grass. Isotopic estimates of rco2 were compared with respiration chamber measurements of rco2. A number of curve fitting procedures were considered together with three multi-point, three ratio plot and three two-point estimations of rco2. Using a multi-point calculation and after making corrections for fractional water loss, loss of 2H in methane and faecal solids, rH20 was underestimated by 16.24%. The isotopic rco2 estimates were on average 1.52% (SD 15.31) lower than the chamber measurements, although one animal was markedly different from the others, omitting this animal led to an average error of + 5.95% (SD 4.34). In applying this technique to animals in the field the influence of a free-living existence on the performance of the method was assessed. A number of rco2 calculation procedures were again considered. Preliminary chamber measurements were used to estimate methane production and faecal dry matter output in the field. Estimates of rH2O in the field (mean 7.218.1. day-1) were lower than those measured in the chambers (mean 9.812 1.day-1). From predictions of dry matter intake in the field RQ was estimated (mean 1.067), using the isotopic rco2 estimates (mean 590 1.day-1) energy expenditure was then predicted (mean 11586 kJ.day-1). In the light of this work it was concluded the DLW technique may be usefully applied to ruminant animals and a number of practical suggestions were made.
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Kassem, Riad. "Reproduction in the Awassi ewe particular reference to increasing efficiency under semi-arid conditions." Thesis, Bangor University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328270.
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Richmond, Susan Emily. "Assessing the welfare of extensively managed sheep : an evaluation of animal-based welfare indicators." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/28677.
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The increased public interest in the welfare of animals used in food production has led to the emergence of welfare assessment schemes for a range of livestock species. There are currently over 100 million sheep in the EU which are primarily bred for milk, meat and wool production and the majority of these animals are managed extensively. The general perception of sheep in extensive systems living “natural lives” with few welfare compromises, along with the practical challenges of adequately assessing their welfare, has caused them to be largely ignored in comparison to other species. It was only relatively recently that the lack of animalbased welfare assessments for extensively kept small ruminants was recognised. Thus, the aim of this project was to evaluate potential animal-based welfare indicators for use during on-farm welfare assessments of extensively managed sheep. The current project used the Welfare Quality® 4 principles and 12 criteria as a foundation for selecting indicators for the assessment of extensively managed sheep. Following a comprehensive review of the scientific literature and a meeting attended by experts from across the EU, 16 indicators were selected for evaluation. Each principle and criteria were covered by at least one of these 16 indicators ensuring the main aspects of sheep welfare were addressed. The indicators selected for investigation could either be applied without handling or gathering the animals during an 'Assessment in the Field', or during a more thorough hands-on 'Assessment at Gather'. The reliability, feasibility and validity of some indicators (e.g. body condition scoring) are already established. However for others (e.g. Qualitative Behavioural Assessment approach), at least one of these criteria required further investigation before the indicator could be accepted. The reliability of selected measures was evaluated by assessing their repeatability and inter-observer agreement. Face validity was assumed for the indicators selected during the expert meeting, and further cross validation was performed when appropriate using additional information collected on the animal’s physical health status. During the Assessments at Gather blood samples were collected for the assessment of metabolic profiles, and faecal samples provided gastro-intestinal parasite counts. The Assessments at Gather were performed on the same 100-135 Scottish Blackface ewes across a two year period (2011-2013) on a Scottish hill farm. The Assessments at Gather occurred five times a year coinciding with key points in the ewes’ reproductive cycle: pre-mating, mid-pregnancy, late pregnancy, mid lactation and weaning. During the assessments data were collected on the ewe’s body condition, coat cleanliness, faecal soiling score, respiratory conditions, anaemia, lameness and udder condition (udders assessed during lactation only). Current stage in the reproductive cycle and seasonality were found to have significant impacts upon the long-term reliability of the following measures: body condition score, tooth loss, nasal discharge and anaemia scores (P < 0.001) with variation both within, and between years. On commercial farms older and less productive ewes tend to be removed from the flock once a year prior to mating. Of the indicators applied to the ewes during the Assessments at Gathers, tooth loss and body condition score were the best predictors for the ewe’s exclusion from the flock, predicting the future removal of a ewe from the flock 12 months in advance of the shepherd’s decision. For the Assessments in the Field, indicators which did not necessitate close contact were required. A whole-animal method (Qualitative Behavioural Assessment (QBA) was therefore particularly useful as it can be performed with minimal disturbance. Rather than quantitatively scoring the behaviour patterns of an animal the assessor focusses on how the animal interacts with their environment. This information is translated in to qualitative descriptors such as “calm” or “agitated”. Good interobserver reliability was found when three observers assessed 49 individual ewes on two occasions (W=0.77, P < 0.001). When QBA was applied 13 times to 50 individual ewes over a six-month time period (spanning late pregnancy to post-weaning) four meaningful Principal Components were identified; the first two accounted for more than half of the explained variation between sheep. The two main components were ‘General Mood’ (PC1), describing the overall affective state of the ewe, and ‘Arousal’ (PC2) reflecting energy levels. General Mood scores significantly increased in the post-lambing period compared to pre-lambing observations, and significantly increased again post-weaning (P < 0.001). Ewes were significantly experiencing significantly higher Arousal in post-lambing and post-weaning conditions compared to pre-lambing (P < 0.001), but there was no difference between post-lambing and post-weaning. During the Assessments in the Field data were also collected on: the ewe’s response to human approach, a surprise test, the ewe’s social group size, group demographics and behavioural synchrony. Ewes with lower mood scores tended to have larger distances between them and other ewes (P=0.023). The distance to which a human could approach before the ewe fled was significantly related to Arousal (P=0.05), as ewes in a higher energy state fled from the approaching human sooner than those who were in lower Arousal states. Ewes in social groups with higher numbers of ewe and lamb vocalisations tended to have lower General Mood scores (P=0.014), and lower Arousal scores (P < 0.001) than those in smaller groups. Indicators which met the conditions of feasibility, reliability and validity (for example, those reported above) proved to be suitable for use when assessing the welfare of extensively managed sheep. The effect of time on the reliability of the indicators applied during the assessments have important implications for understanding temporary fluctuations in the animal’s welfare caused by either internal (reproductive state) or external (environmental) factors. These fluctuations may not be representative of a farm’s overall welfare levels in the long term and therefore further careful consideration of the most appropriate time to apply the selected indicators is required.
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Colombo, Luca. "Technology adoption with production externalities." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973252863.
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Ludemann, M. R. "Development of an experimental approach to measure vitamin B12 production and absorption in sheep." Lincoln University, 2009. http://hdl.handle.net/10182/1424.
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Clinical diagnosis of vitamin B12/cobalt (Co) deficiency is difficult due to the unspecific nature of the clinical symptoms. The apparent increase in vitamin B12 deficiency in New Zealand in the late 1990’s made it clear that health providers were very reliant on plasma reference ranges to diagnose deficiency. However, the lack of quantitative data of what these reference ranges represent in terms of supply of vitamin B12, has prevented a better understanding of the metabolism of vitamin B12 within sheep. This thesis describes the development of an experimental approach to measure vitamin B12 production and absorption in sheep. The model was then used to investigate whether the type of carbohydrate source affects vitamin B12 production and/or absorption. In the first trial (Chapter 4), an adaptation of the repletion technique of Suttle (1974) for copper was used. Previously vitamin B12 depleted sheep were maintained on a diet of 400 g DM meadow hay and 250 g DM crushed barley and which provided a daily intake of 0.03 mg Co. Sheep were intravenously infused with known quantities of vitamin B12 (0 – 200 nmol hydroxycobalamin/d) to determine whether a relationship exists between plasma vitamin B12 concentration and rate of entry of the vitamin into the bloodstream and to quantify the relationship. Eight ewes fitted with rumen and abomasal cannulae were used in a paired 4x4 Latin square design. Four levels of vitamin B12 were infused into the jugular vein for 4 d followed by recovery period of 17 d and the plasma responses measured during this period. Control animals maintained relatively stable plasma levels while levels in treated animals rose sharply within 4 h after the start of infusion. The responses were proportional to infusion rate with a highly significant difference in concentrations observed between treatments (P<0.001). Appearance of vitamin B12 in the plasma was quantified by the relationship Y(pmol/l) = 238 + 102x0.74 where x = infusion rate(nmol B12/d), R² = 0.945. Plasma levels declined rapidly on cessation of infusion and had returned to original pre-treatment levels by the end of the recovery period. The second trial (Chapter 5) quantified plasma responses in relation to dietary Co supply to the rumen. The same eight rumen and abomasal cannulated ewes were used in a paired 4x4 Latin square with 4 levels of intra-ruminal Co infusion in amounts ranging from 0 – 1 mg Co/d as CoSO₄, infused for 4 d followed by a 19 d recovery period. Plasma vitamin B12 response was measured as were concentration of vitamin B12 in abomasal digesta supernatant and digesta liquid flow, the latter using polyethylene glycol as liquid phase marker. Plasma concentration increased from approximately 300 pmol/l to 750 – 800 pmol/l, peaking at day 5 after commencement of infusions. Control animals infused with water maintained base-line plasma vitamin B12 levels around 250 pmol/l. Digesta liquid flow was estimated at 14.6 l/d. The results from Chapters 4 and 5 allowed estimates of vitamin B12 production and absorption. These results are discussed and efficiency of capture of Co into vitamin B12 from dietary Co intake was estimated to decrease from 8.4% to 0.74% as Co intake increased from 0.03 to 1.11 mg Co/d. Absorption coefficient was estimated from the relationships between abomasal vitamin B12 flow and plasma response. The absorption coefficient was calculated to increase from 7 to 10% as abomasal vitamin B12 flow increased from 108 to 142 nmol/d. The current animal model was subsequently used in the final trial (Chapter 6) to investigate whether the type of carbohydrate supplied in the diet influences vitamin B12 production and absorption. The same eight ewes fitted with rumen and abomasal cannulae were used in a 2x4 cross-over design. Half of the ewes were maintained on the basal diet and crushed barley while, for the remainder, the barley was replaced by 250 g of fructose:sucrose in a 80:20 mix during a 7 d period of adaptation. While on their respective diets, both groups were then infused with 0.3 mg Co/d for 6 d, a level chosen to optimise plasma vitamin B12 response. All ewes were then returned to the basal diet and barley for a 15 d recovery period after which treatments were reversed and the procedure repeated. Rumen pH, valeric, propionic, butyric, succinic, and acetic acid and ammonia concentrations were not significantly affected by diet. Digesta flow was 30% greater on a diet enriched with starch compared to sugar-enriched diet. There was an observed difference in vitamin B12 production. However there was no significant diet x time effect on plasma vitamin B12 concentration so any difference in production was negated by a difference in absorption. Carbohydrate supplied as water soluble carbohydrate or starch does not appear to influence plasma vitamin B12 concentration.
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Tanner, Jonathan Christian. "Cut-and-carry feeding indigenous forage for sheep and manure-compost production on Java." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262639.
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Muttukrishna, Shanthi. "In vitro effects of ovarian peptides and steroids on pituitary gonadotrophin production in sheep." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315435.
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Yaqoob, Muhammad. "Comparison of three terminal sire breeds for lamb production under upland grassland conditions in the North East of England." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313239.
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Pereira, Igor Daniell Costa. "Economic values for production traits of Morada Nova meat sheep in a pasture based production system in semi-arid Brazil." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16343.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃThe economic values for traits of a meet sheep production system were calculated using Morada Nova hair sheep, raised under the conditions of native pasture in the Brazilian semi-arid region, as model. These economic weights were estimated using the equation of profit, profit = revenue â costs, after increase by one unit and 1% for each trait, evaluated on the average of the others. Whereas 1% increase in the trait, the economic values for lambing percentage (LP), litter size (LS), lambs mortality (LM), yearling mortality (YM), ewes and rams mortality (AM), female slaughter weight (FSW), male slaughter weight (MSW), ewe adult weight (EAW), ram adult weight (RW), carcass yield (CY), number of lambings per year (NLY), age at first lambing (AFL) and number of anthelminthic doses used per year (AC) were 1,439, 1,439, -0,254, -0,110, -0,054, 0,487, 0,767, -0,172, 0,005, 1,523, 1,439, -0,258 and -0,025, respectively, expressed in Brazilian currency (R$) per ewe per year. The traits that showed greater economic importance were CY, NLY, LP and LS. The traits that showed lower economic values were: RW, AC and AM. The production system with Morada Nova sheep grazing native âcaatingaâ pasture in Brazilian Northeast, exclusively for meat production, is profitable when taking into account all costs of production, including that of family labour. Carcass yield was shown to be an important selection objective. As it is expressed when the animal is slaughtered, further studies need to be carried out with this population to aid in the choice of appropriate selection criteria for the improvement of this trait.
Os valores econÃmicos para caracterÃsticas de produÃÃo de carne de ovinos foram calculados considerando-se como modelo o sistema de produÃÃo com a raÃa Morada Nova, criada sob as condiÃÃes de pastagem nativa do semi-Ãrido brasileiro. Os ponderadores econÃmicos foram estimados utilizando a equaÃÃo de lucro, lucro = receita - custos, para aumento de uma unidade e de 1 % em cada caracterÃstica, avaliada no valor mÃdio das demais. Com o aumento de 1% nas caracterÃsticas (R$ por ovelha ano) os valores econÃmicos para fertilidade ao parto (FP), prolificidade (PRO), mortalidade de cordeiros (MC), mortalidade de borregos (MB), mortalidade de ovelhas e carneiros (MA), peso de fÃmeas ao abate (PAF), peso de machos ao abate (PAM), peso maduro das matrizes (PM), peso dos reprodutores (PR), nÃmero de partos/ano (NPA), idade ao primeiro parto (IPP), rendimento de carcaÃa (RC) e nÃmero de tratamentos parasitÃrios/ano (TP) foram 1,439, 1,439, -0,254, -0,110, -0,054, 0,487, 0,767, -0,172, 0,005, 1,523, 1,439, -0,258 e -0,025, respectivamente. As caracterÃsticas que apresentaram maior importÃncia econÃmica foram RC, NPA, FP e PRO. As caracterÃsticas que apresentaram menor peso econÃmico foram: PR, TP e MA. O sistema de produÃÃo com ovinos Morados Nova em pastagem nativa (caatinga) no Nordeste brasileiro, exclusivamente para a produÃÃo de carne, Ã rentÃvel quando se toma em conta todos os custos de produÃÃo, incluindo o de mÃo de obra familiar. O rendimento de carcaÃa foi mostrado a ser um objetivo importante seleÃÃo. Como ela se expressa quando o animal for abatido, estudos adicionais necessitam de ser realizadas com esta populaÃÃo para ajudar na escolha adequada de critÃrios de seleÃÃo para a melhoria desta caracterÃstica.
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Leask, Rhoda. "The effect of application of the FAMACHA© system on selected production parameters in sheep." Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/30511.
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A trial was conducted on a farm comprising a flock of approximately 300 Mutton Merinos on which the FAMACHA© system was in use. Seventy five maiden and multiparous ewes were blocked by class before being ranked by weight and then
randomly allocated using block randomization, with due regard to approximately equal apportioning of the two classes of ewes, to the following three trial groups:
(i) FAMACHA© (FMCH) group, in which only animals evaluated to be in FAMACHA©
categories 4 and 5 (overtly anaemic) were treated with levamisole HCl 2,5%
(Nemasol NF, Intervet)
(ii) Strategically dosed (STRAT) group, blanket treated every six weeks with levamisole HCl 2,5% (Nemasol NF, Intervet)
(iii) Suppressively dosed (SUPPR) group, blanket treated at the same intervals with injectable moxidectin 1% (Cydectin, Bayer AH) The trial was set to take place during the period of high haemonchosis risk (December to April) but data was recorded from November 2006 to July 2007. However, the deworming schedule of the trial only commenced in February 2007, due to Cydectin being out of stock until that time. All the trial animals were evaluated once weekly according to the FAMACHA© system, and Faecal Egg Counts (FECs) were performed on
all groups prior to commencement of the trial, as well as during the trial period. Initial analysis of the results of all ewes, regardless of class, appeared to show that the
FAMACHA© group gained, on average, 3-4 kg less (P<0.05) than the other two groups. However, these results compared groups which contained both pregnant and nonpregnant
ewes. Within each treatment regimen the multiparous ewes, which accounted for most of the pregnancies, were responsible for the largest difference in weight gains. Data from ewes
that became pregnant during the trial period was separated from the data of non-pregnant ewes, and analysed because the pregnant ewes did not lamb down in the same week and
cannot therefore be used as an accurate comparison as they were in different stages of pregnancy at any given time. The pregnant ewes’ data was then ranked according to
weeks before lambing and re-analysed. When the data was analysed separately for ewes that conceived during the trial and ewes that did not conceive, the results showed that
there was no significant difference in weight gains amongst the three treatment regimens (Figure 4.2).
There were no significant differences in lamb weights (Table 4.3.3) nor average daily gains (ADG), as can be seen from Tables 4.4.1 to 4.4.3. Wool production was not analysed in this trial due to faulty sample collection at shearing, but ideally it should have
been included. Economic evaluation of the data initially showed that there appeared to be a benefit to dosing more frequently. During the trial period the total cost of deworming the SUPPR
group was R163.51 and the liveweight gain gave an additional income of approximately R2758.00 resulting in a calculated financial gain of R2594.49 for 25 ewes when compared to the FMCH group. The cost of deworming the STRAT group for the trial
period was R 104.65 and the liveweight gain gave an additional income of approximately R2261.00 which resulted in a financial gain of R2156.35 in comparison to the FMCH group for 25 ewes. The cost for deworming the FMCH group was R10.96 for the
duration of the trial. However, these calculations were based on both pregnant and nonpregnant ewe data combined and therefore do not accurately reflect the cost and return
for the farmer of meat had the pregnant ewes data been analysed together with those that did not fall pregnant during the trial. Once the pregnant ewes were separated from the
rest, there was no significant difference between the three groups regarding liveweight gain. Therefore there was no financial benefit to the farmer in deworming either
suppresively or strategically and in fact resulted in an economic loss due to the cost of anthelmintic when compared to using the FAMACHA© system. A shortage of feed due to unseasonal downpours leading to poor Body Condition Scores
(BCS), forced the farmer to supplement the grazing and the FMCH group was able to make use of compensatory growth so that by the end of the trial, the was no significant
difference in BCS between the groups. The FAMACHA© system allows for selective targeted use of anthelmintics, and studies
to date are contradictory on whether or not production is significantly affected by applying the FAMACHA© system to control H. contortus. However, this trial concluded
that there is no significant difference in selected production parameters when using the FAMACHA© system as opposed to other methods of anthelmintic use in a Mutton
Merino flock in a semi-intensive farming system. The FAMACHA© system is therefore the preferred method of worm control, where the major parasite problem is Haemonchus
contortus, as other methods compared in this trial are not sustainable with regards to the worldwide increase in anthelmintic resistance (AR) and now with the increase in multiple anthelmintic resistance (MAR) on certain farms. It is also evident from this trial that the FAMACHA© system cannot be used in isolation as nutrition also plays a vital role in
resistance and resilience of individual animals. Therefore if nutrition and other management practices are poor, the FAMACHA© system cannot be blamed for financial
and production losses.Dissertation (MMedVet)--University of Pretoria, 2010.
Production Animal Studies
unrestricted
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Fadel, I. "Economic and technical aspects of lactation in Awassi sheep with special reference to simplified recording and system development under semi-arid conditions." Thesis, Bangor University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380212.
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Ribeiro, Mafalda Maria dos Santos Vidal. "Caracterização produtiva e reprodutiva do rebanho de raça Merino Branco da Fundação Eugénio D'Almeida." Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5296.
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Terblanche, Stefan. "An economic analysis of an intensive sheep production system on cultivated pastures in South Africa, incorporating creep feeding- and accelerated breeding practices." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020939.
Full textAbstract:
The South African sheep industry has experienced an increase in the price of meat and wool over the past several years. This has led to an interest in intensification of sheep production off planted pastures. Due to this phenomenon an economic viability study was done on the intensification of sheep production on cultivated pastures under irrigation. When intensifying sheep production, certain management practices need to be incorporated in order to enhance the output obtained per hectare and to overcome the higher input cost of production. Management practices that could be included are creep feeding, accelerated breeding and feedlotting of lambs after weaning. In order to determine the economic viability of such a system, certain production parameters need to be obtained for producing sheep intensively from cultivated pastures. Three studies were conducted to obtain the required production parameters; these were then followed by an economic evaluation incorporating the parameters obtained from the studies. All the studies were conducted at Kromme Rhee and Langgewens, two research farms of the Department of Agriculture in the Western Cape.
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Fichtali, Jaouad. "Production of caseins using extrusion technology." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74580.
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Preliminary experiments indicated that an acid casein co-precipitate could be produced by extrusion from skim milk powder (SMP). In assessing the problems encountered, experiments were designed to model and optimize the coagulation/washing process using response surface methodology (RSM), to minimize residual whey components and losses of fines. This study yielded useful information relative to improving our understanding of the coagulation mechanism and the most important variables affecting the process. In addition, RSM allowed multiresponse optimization of acid casein production using unique and newly developed optimization techniques. In order to simplify the process, an extruder die was designed to assist with the dewheying process, however, plugging problems occurred due to screw design limitations. Studies were implemented to determine the rheological behaviour of sodium caseinate and to evaluate the extruder performance in terms of energy consumption, and in terms of mixing and conveying through mathematical description of residence time distributions in the extruder. The knowledge gained from these studies was integrated to produce acid casein and sodium caseinate at pilot plant level and to conceive a plant layout of the process for the dairy industry. The process developed has many advantages, including the ability to produce a high quality product.
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Zhang, Boyang. "Development of Prediction Models of Methane Production by Sheep and Cows Using Rumen Microbiota Data." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1534524559001648.
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Warui, Harun Maina. "Characterisation of sheep and goat genetic resources in their production system context in Northern Kenya." Göttingen Cuvillier, 2009. http://d-nb.info/993633765/04.
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Jensen, Rebekah Paige. "Plane of Energy Nutrition on Blood Metabolites, Milk Production and Lamb Growth in Friesian Sheep." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6857.
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Small ruminant species are utilized for their diverse products including meat, dairy products, and wool. Effective and humane management are essential to maintain high production rates and comfortable animals. To attain this objective, managers needs to have an extensive knowledge of husbandry techniques, understanding of physiological processes, and familiarity with nutritional requirements. We examined the effects of varying feed components on two different ruminal species. In Chapter 1, we conducted a study to evaluate"¯the effects"¯of a low metabolizable energy (LME) and high metabolizable energy (HME) diet on twenty-two Friesian/Lacuane"¯cross ewes and lamb nutritional status."¯Effects on milk production during early lactation stages"¯and the growth of the neonatal lambs were also investigated. We anticipate energy levels will have an effect on milk production and lamb growth. Our results indicate that ewes on the LME diet produced more milk with higher concentrations of fat though this group maintained lower body condition. We concluded that neither the HME nor the LME diet met the needs of the sheep due to the shift in nutrient partitioning towards milk production rather than allocating nutrients to maintaining both body condition and milk production. Limited energy requirements are further evidenced by the decline in back fat (BF) for both the HME and LME groups for the duration of the study. We determined the degradation parameters of grass hay supplemented with soybean meal (SBM) and the effects of SBM on compartment 1 (C1) ammonia and volatile fatty acid (VFA) concentrations in alpacas. Our findings show that the degradation rate was not different for dry matter (DM), but it was for crude protein (CP) (P<0.05). With this data it can be concluded that SBM can be a CP supplement when the diet is insufficient to improve microbial yield. It should be noted that care should be taken to avoid causing a protein-energy imbalance. The results of these two studies indicate shifts in nutrients availability and changes in feeding strategies can affect both the health of the animal and their subsequent offspring.
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Kirkpatrick, Denise Elizabeth. "The effects of diet utilization on metabolizable energy utilization and carcass composition in beef cattle and sheep." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295414.
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Flynn, James Norman. "The development and application of sheep monoclonal antibody technology to epitope mapping of viral synthetic peptides." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/29762.
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Mapiliyao, Luke. "Sheep production practices, flock dynamics, body condition and weight variation in two ecologically different resource-poor communal farming systems." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/340.
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The objective of this study was to determine sheep production practices, constraints, flock dynamics, body condition and weight variation in two ecologically different resource-poor communal farming systems of the Eastern Cape Province of South Africa. Mean sheep flock sizes per household were not significantly different between the two ecologically different areas (villages); Gaga (19.0±3.10) and Sompondo (18.3±3.10). Shortage of feed, disease and parasite were reported the most important constraints across the two villages. In both villages, sheep housing was poorly constructed using acacia brushwoods. Fewer farmers owned rams: the rams to ewes ratio for the two villages were 1:20, 1:19 for Gaga and Sompondo, respectively. The low ram: ewe ratios reported suggest that inbreeding might have been reducing productivity of their flocks. There was also uncontrolled breeding due to undefined and mating seasons. Gall sickness, heart water and footrot caused most of the sheep mortalities. Dohne Merinos were the common genotypes in the two villages. Total entrances for each flock were higher (p < 0.05) in hot-dry season and hot-wet season than in other seasons. Most of the entrances were lambs and were born in hot-dry season (September) and cool-dry season (June) for larger flocks (10.90 ± 3.02) and for small flocks (3.65 ± 3.02). High lamb mortalities were experienced in the post-rainy (April) and hot-wet (December) season. There was a significant interaction between season and flock size. Most of the sales occurred in the hot-wet season. Ecological area had significant effect on sheep production potential (p < 0.05) in both flock classes. The average sheep production efficiency (SPE) value for Gaga and Sompondo were 0.50 ± 0.116 and 0.50 ± 0.096 respectively. The SPE for large flock was higher (p < 0.05) by season and flock size. Large flocks had a higher (p < 0.05) SPE values and the SPE ranged from 1.11 ± 0.193 in April, a post-rainy season month to 1.55 ± 0.193 in December, a hot-wet season month. Lamb mortalities constituted the greater part of outflows. High lamb mortalities occurred in hot-wet (December), hot-dry (September) and post-rainy (April) seasons. There was a significant interaction between season and age of sheep on body weight of sheep. Highest (p < 0.05) body weights were recorded in the post-rainy and autumn season in both lambs and ewes. It is therefore very important to come up with affordable interventions which take into play ecological differences of the areas for improved nutritional status of sheep in communal areas which will lead to improved sheep productivity and the poor-resourced farmer human nutritional and livelihood.
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Mason, Susan Leigh. "Metabolism of triacylglycerol-rich lipoproteins in sheep." Lincoln University, 1991. http://hdl.handle.net/10182/1756.
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This thesis describes two approaches for studying of lipoprotein metabolism in sheep. The first approach involves the assay of lipoprotein lipase (LPL) activity to determine the role of lipoprotein-triacylglycerol fatty acids in fat deposition in sheep. This enzyme is the rate limiting enzyme in the hydrolysis of fatty acids from lipoprotein-triacylglycerol. The second approach was to characterize and quantify in vivo lipoprotein metabolism using iodinated very low density lipoprotein (¹²⁵I-VLDL) and low density lipoprotein (¹³¹I-LDL). Cross-bred lambs were divided into two treatment groups and either weaned early at 5 weeks of age or remained suckling. Lambs were slaughtered at 12 or 23 weeks at which time the body composition and adipose tissue LPL activity were determined. The differences in rearing led to differences in body composition. The suckled lambs were larger and fatter than weaned lambs. The increased fatness in the suckled lambs was associated with increased LPL activity (U/mg protein) in subcutaneous adipose tissue and was reflected in higher LPL activity in post-heparin plasma (PHP) taken 2 days prior to slaughter. The role of insulin in the regulation of LPL activity was investigated by either infusing a subset of the weaned and suckled lambs with insulin for 7 or 18 weeks or using the euglycemic clamp technique to study the effect of short insulin infusions. The long term infusion of insulin had no significant effect on PHP LPL or on adipose tissue LPL (U/g tissue). However, after infusing insulin for 6h at 6.3 mU.kg⁻·⁷⁵.h⁻¹ during the euglycemic clamps, a two fold increase in LPL activity in biopsied subcutaneous adipose tissue was observed. In the second approach, in vivo lipoprotein metabolism was investigated in 4 lambs using apolipoprotein B as a marker. Following the simultaneous injection of ¹²⁵I VLDL and ¹³¹I VLDL, the specific activities of apoB in VLDL, IDL and LDL fractions were determined. ApoB specific activity curves demonstrated that VLDL is metabolised to IDL and subsequently to LDL. The turnover of VLDL-B (3.45mg.d⁻¹.kg⁻¹) and LDL-B (4.8mg.d⁻¹.kg⁻¹) was calculated by fitting the VLDL-¹²⁵I-B and LDL-¹³¹I-B specific activity data to a mono-exponential equation. The metabolism of lipoproteins, inferred from the study of apoB, was shown to be similar in sheep to that reported in other animals although the amount of lipoprotein synthesised was low. A model to describe the kinetics of apoB metabolism in sheep was developed using SAAM. The proposed model features a three pool delipidation chain for VLDL, and subsystems containing two pools for IDL and LDL. IDL may be catabolised to LDL or cleared directly from the plasma. The developed model can now be used to compare the metabolism of lipoproteins in different physiological states and to design new experiments to study lipoprotein metabolism further.
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Lion, Majed, and Daniel Ramström. "Production Analysis." Thesis, KTH, Tillämpad maskinteknik (KTH Södertälje), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-222274.
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