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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Protein and sulfur amino acid requirements of male and female breeder turkeys

Parsons, Martha Anne Cohen January 1979 (has links)
One hundred eight male and 206 female breeder turkeys were fed isocaloric corn-soy rations containing 8, 10 or 12, and 10, 12 or 14'% crude protein, respectively, to which 0.0, 0.1, 0.2, or 0.3% DL-methionine was added in a factorial arrangement of treatments,. With the exception of percentage hen-day egg production and egg size, dietary treatment had no significant effect on the reproduction of females or on the growth of the progeny. Egg production was higher among females fed 12 and 14% protein than among those fed 10% protein. Those fed 14% protein laid the heaviest eggs. Female serum albumin concentrations and the concentrations of blood threonine and lysine significantly increased while concentrations of blood glycine decreased with increased levels of dietary protein. Optimum semen volume and spermatozoa concentration were obtained for males fed 10% protein. For females, the significant response obtained in egg production to increased protein levels and the failure to obtain this response with increased total sulfur amino acid (TSAA) levels as a percentage of total protein, indicates that other amino acids may have been limiting. Based on these results, it appears that for optimum reproduction of Medium White breeder turkeys, a daily intake of at least 22.7 g protein and 696 mg TSAA are necessary for females, and 25.0 g protein and 1,175 mg TSAA are necessary for males. / Master of Science
62

Development of computer models of different selection strategies on poultry egg production.

De Guisti, Jonathan. 18 October 2013 (has links)
Poultry have many behavioural, structural and biological features that are ideal for domestication and for meat and egg production (Appleby et al., 1992). Because of the importance of poultry meat and eggs to the human population, breeders and farmers are always looking for ways of improving these traits. Artificial selection is the primary method of trait improvement, and involves selecting individuals with the highest breeding values as parents in each generation. There are a number of different methods of artificial selection, including: individual selection, between family selection, within family selection, family-index selection and index selection. In order to maintain a good response to selection breeders are constantly striving to improve the effectiveness and accuracy of the different methods of artificial selection for traits of economic importance. One method of achieving this goal is the use of computer models. Computer models can be used to simulate selection strategies and to predict what strategy will be the most appropriate for the improvement of a particular trait. This is important as all traits are influenced by many different genetic and environmental factors (Falconer and Mackay, 1996). This investigation was designed to compare the effectiveness of five different artificial selection strategies, namely individual selection, between family selection, within family selection, family index selection and index selection. Five computer models were developed using Microsoft Excel 2000 and these models were then used to compare the efficiencies of the five selection strategies for four different traits. The selection techniques were applied to an artificially, randomly generated population of 500 chickens. The four traits were egg weight with a heritability of 0.51, egg production with a heritability of 0.22, age at first egg with a heritability of 0.41 and body weight with a heritability of 0.55. Firstly, each of these traits were selected for independently using the first four selection methods and secondly the traits were selected for two at a time using index selection. The most significant results obtained from the single trait simulations were that for all traits family-index selection produced the best response to selection in the initial generations and between family selection produced the best response in the later generations. The traits with a higher heritability (egg weight and body weight) responded better to individual selection than they did to within family selection and between family selection in the initial generations. However, within family selection and between family selection proved to be more effective for traits with a low heritability such as egg production. Individual selection and family-index selection resulted in a very rapid decline in the standard deviation of all the traits. Between family selection resulted in the slowest drop in the standard deviation of all the traits, which is why this technique produced the best responses to selection in the later generations. The impact of the correlations between the economically important traits were evident from the results of index selection. For example, egg production is negatively correlated with egg weight making it difficult to gain a correlated response in both these traits simultaneously. Furthermore, egg production is negatively correlated with age at first egg implying that early maturing birds will lay more eggs, however, these eggs will be lighter. The majority of the results obtained were to be expected. Family-index selection takes all the information about an individual's breeding value into account resulting in this method of selection consistently identifying the most desirable individuals being selected. It is therefore the preferred method of selection under all circumstances. It is, however, often not economically and practically efficient to incorporate this technique and the use of another method of selection usually proves to be more beneficial. Individual selection proved to be most effective when applied to traits with high heritabilities, due to the fact that this method selects individuals based on their own phenotypic values. For traits with a high heritability, an individual with a good phenotypic value will have a good breeding value. Between family selection and within family selection proved better for traits with lower heritabilities. For traits with a low heritability the phenotypic value of an individual is a poor indicator of its breeding value. Information from a number of relatives may thus improve the accuracy of prediction of the breeding value by accounting for the influence of environmental effects. The use of computer models to simulate the selection techniques proved very successful in illustrating the effectiveness of the different selection techniques under various genetic and environmental conditions. The models may also prove to be very effective from an educational perspective. / Thesis (M.Sc.)-University of Natal, Pietemaritzburg, 2003.
63

Towards the modeling of indigenous poultry production in the Eastern Cape Province, South Africa: characterization and extension evaluation for poverty reduction

Yusuf, Shehu Folaranmi Gbolahan Shehu January 2014 (has links)
Poverty remains a critical issue mostly in the rural South Africa. Various initiatives, policies and programs have been enacted by the government with attempting to reduce poverty at the national and provincial levels; poverty is yet to be abated. The target of the Millennium Development Goal 1 (MDG1) of halving poverty by the year 2015 notwithstanding, poverty remains a threat to quality livelihoods. Agriculture has continued to be one of the pillars of government efforts to address poverty. However, in livestock production interventions, efforts of government had largely been on cattle, sheep, goats, pigs and exotic poultry with little attention being given to indigenous poultry production (IPP). This study explores the option of using IPP to address rural poverty by capitalizing on its minimal inputs while recognizing its prevalence in a variety of households. The study addresses the characterization of the IPP from the perspectives of housing, feeding, healthcare management, breeding and marketing options.Skill competencies of the indigenous poultry farmers (IPFs) and the Agricultural Development Technicians (ADTs) were examined. This study reviewed poultry models in different parts of the world with special attention to Africa. The human resource development program of the department of rural development and agrarian reform was discussed. The study employed the use of multi-methods approach, the quantitative and qualitative research methodologies. Descriptive statistical analysis, frequent count, percentage, means, standard deviation, chisquare, and principal component analysis was used in the quantitative data analysis while the “open social system” was used for the qualitative methodology. Findings revealed that IPFs face some challenges among which are, the poor housing that exposed the birds to inclement weather, predator attacks and stock theft, high mortality of chicks after hatching and expensive feed for the flock. The IPFs showed competencies in nine skill items that included ability to identify chicken predators (x=3.92) and high yielding chickens (x=3.79); control of predators(x=3.77); methods of using ethno veterinary drugs to treat chicken diseases and pests (x=3.72), and identify signs of diseases (x=3.69), among others. However, the ADTs did not show any competency in any of the 32 skills items. The principal component analysis with Varimax rotation was performed to ascertain the dimensionality of the measures. Six factors with eigen value of >1, which accounted for 77.317% were extracted, with each factor loading ranging from 0.523 to 0.93. Factor loading after rotation that emerged on the same component was described; as brooding, shelter and care of the chicks; predators and healthcare; hygiene and litter management; feeds and feeding stuff; and record keeping and marketing. The findings on the human resource development revealed that staff meetings were the most common method of capacity development. This was followed by in-service-training, formal study, workshop, and on the job training. The farmers’ field school and study tours were sparingly used. However, respondents were in favor of on-site training, staff meetings, formal study and in-service training. The findings on the appropriate model suggest a theoretical indigenous poultry production model (IPPM) for the Eastern Cape Province (ECP). The “open social system” was used to develop a framework for an indigenous poultry cooperative society (to be known as Abafuyi Benkukhu Zemveli [ABZ]). This was meant to create a binding force for capacity development, a strong economic foundation through equity contributions, creation of marketing channels, and the development of a concept of ‘‘our own'' product in the market. Lastly, the study offers options for a training program that would accommodate the new initiatives, with a strong capacity development training approach. In this context, the study advocates for institutional support for the IPFs and the incorporation of indigenous poultry in the curriculum of the agricultural training programs at higher education institutions in South Africa.
64

The influence of slat material, slat coverage and breeder age on broiler breeder reproduction and progeny growth

Decolongon, Joji January 1990 (has links)
This study was conducted to examine the potential of plastic slats as flooring material for maintenance of broiler breeders. Although plastic slats are more expensive than wood slats, plastic slats are more durable and easier to clean. Wood and plastic slats were tested as full and partial flooring to determine the ideal proportion of slats for broiler breeder floors. Space allotment was 2040 cm²/bird on all floor treatments. . Arbor Acres broiler breeders, one of the more common strains in British Columbia, were raised to 58 weeks of age to monitor the influence of slat material and slat coverage on egg production and progeny growth over one production cycle. Since the pens were not set up to determine the number of eggs lost through slats, "egg production" values were actually egg recovery values. Over-all egg recovery was significantly higher on partial wood (PWS) and partial plastic slats (PPS) than on either of the full slat treatments. Breeders on full wood slats (FWS) had higher over-all egg production than those on full plastic slats (FPS). Differences were significant for three biweekly periods, but slats did not influence the over-all incidence of floor eggs and cracked floor eggs. The incidence of cracked nest eggs was significantly higher in FWS and FPS than in PWS and PPS pens during four lay periods and overall. The proportion of non-cracked nest eggs, which was taken as an approximation of the proportion of settable eggs, was higher for partial slat pens than full slat pens, and FWS pens had a higher proportion of non-cracked nest eggs than FPS pens. To monitor fertility and hatchability, eggs were incubated at 37, 42, 46, 50 and 56 weeks of breeder age. Fertility, hatchability of total eggs set and hatchability of fertile eggs was not affected by type of slats. Progeny from the hatch at 37, 46 and 56 week of breeder age were grown in Petersime battery cages to three weeks of age. The progeny of breeders on FPS had lower first week weight gain than the other progeny groups due to moisture loss when 7 FPS progeny were lost during the second growth trial. Weekly and over-all feed conversion of progeny was not affected by types of slats used by parents. The 56th week progeny were grown in Petersime battery cages to market age (six weeks). PWS and FPS progeny had higher third week weight gain than PPS progeny. During the sixth week, FWS and PWS progeny had higher weight gain than FPS and PPS progeny. The sixth week feed conversion of FPS progeny was higher than that of the other three progeny groups. No other differences were seen. As long as slats were used as partial flooring, there were no differences in egg production on wood or plastic slats. The proportion of "settable" eggs, fertility, and hatchability of eggs of plastic slat breeders were comparable with that of wood slat breeders regardless of slat coverage. There were significant differences in the 3-week growth of 37th, 46th and 56th week progeny and the 6-week growth of 56th week progeny on the different slat types, but the differences were not due to slat treatments. There was no interaction between breeder age and slat material, therefore the influence of slat material on egg production and progeny growth did not vary with breeder age. Although egg recovery and the number of settable eggs were lower for FPS breeders, breeders on plastic slats performed as well as those on wood slats in the present study. / Land and Food Systems, Faculty of / Graduate
65

Gross margin analysis and determinants of savings among small-scale broiler producers in Vhembe District of Limpopo Province, South Africa

Mulaudzi, Vhutali, January 2022 (has links)
Thesis (M.Sc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2022 / The poultry industry consists of the broiler and layer production. Most of the broiler chickens produced by smallholder farmers in villages are sold to local customers with lower degrees of processing, compared to large commercial farmers who have access to retail and export markets. The aim of this study was to analyse the determinants of gross margin and savings among small-scale broiler producers in Vhembe District of Limpopo Province. In the analyses the following objectives were performed; identifying and describing their socio-economic characteristics, assessing their gross margin, analysing the factors influencing their gross margin and lastly, by analysing the factors affecting savings among these farmers. The study was conducted in three municipalities (Makhado, Thulamela and Musina) under Vhembe District, where 60 respondents were purposively and randomly selected. The total number of households per municipality in Vhembe District were used to determine the exact number of broiler producers to be interviewed in each municipality due to insufficient data available regarding the total number of broiler producers in the district. The respondents were interviewed face to face using structured questionnaires. To achieve the study objectives the study used Descriptive statistics, Gross Margin analysis, Multiple Linear Regression and Logistic Regression model. The results of the study showed that the small-scale broiler producers in Vhembe District are profitable, with an average Gross Margin of R6470.78 per cycle. Six variables from Multiple Linear Regression analysis were found to have an influence on Gross Margin among small-scale broiler producers in Vhembe District. These variables were gender, primary economic activity, cost of day-old chicks, feed cost, electricity cost and labour cost. Seven variables from Logistic Regression analysis were found to have significant influence on savings. These variables were age, primary economic activity, monthly income, gross margin, feeds cost, cost of day-old chicks and vaccines. The study recommends that the broiler producers invest in other heating methods that do not require the use of electricity since it plays an important role towards the savings. The study further recommends that the Department of Agriculture should encourage the small-scale broiler producers to register their enterprise to be able to access extension services and other services from the department when necessary.
66

An investigation of the long-run relationship between import tariff, import quantity, production and prices in the broiler section of South Africa (April 2010-June 2022)

Nkgadima, Kgothatso January 2022 (has links)
Thesis (M.Sc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2022 / The agricultural sector is dominated by broiler production and it is the key source of animal proteins followed by beef. South Africa is described as a net importer of chicken meat, given that broiler consumption of broiler is greater than supply. Additionally, the South African Poultry industry has raised concerns regarding the high influx of cheap broiler imports into the domestic market. This led to an increase of the ad valorem tariff charged on poultry imports in April 2020 from a previous adjustment in September 2013. It is vital to understand how import tariff changes affect the broiler sector since little is known about how domestic broiler production is responding to an increased tariff. The study, therefore, attempted to determine the relationship between domestic broiler production, import tariff, domestic prices, and import volume. The study aimed to investigate the long-run relationship between import tariff, import quantity, domestic production, and prices (retail and producer) in the broiler sector of South Africa for the period (April 2010 – June 2020). Brazilian frozen chicken imports were selected for study given their relatively high domestic demand in South Africa. In addition, Brazil primarily faces the import tariffs charged by South Africa as the main country of origin for South African imports. The Augmented Dickey-Fuller test, Johansen Cointegration tests, and the Error Correction Model were used as analytical tools in achieving the study objectives. The results for the Augmented Dickey-Fuller test and the Johansen cointegration test showed that all variables were stationary at first difference and cointegrated. The ECM results concluded the existence of a long-run relationship between domestic production, ad valorem tariff, and import volume. As the tariff charged changes, the domestic production increased by 4% in the long run which might be deemed a small advantage in terms of the production scale and therefore not sufficient. The study recommended that strategies that reduce barriers of entry for small-scale farmers such as reduced production costs be implemented to boost domestic production. Lastly, since domestic production is responding positively to tariff adjustment, a thorough investigation is necessary to prove dumping allegations against broiler importers as this will enable the country to impose anti-dumping duties on all countries. / Agri SETA
67

Koncentrace tuhých znečišťujících látek emitovaných do okolí velkochovů drůbeže.

BLAŽEK, Petr January 2018 (has links)
In this diploma thesis I focus on poultry farms, as a source of dust particles, which are taken from the breeding establishment to the surroundings of poultry breeding. The first theoretical part of the thesis is focused on dust, dust particles and their sources, as well as on housing of poultry and on BAT technology. These particles can be dangerous not only for the animals but also for the staff working in the vicinity of the farm animals. In the second, practical part of the thesis, I focus on the measurement of dust particles PM10 using the DUST TRUK II measuring instrument in a selected broiler breeding facility, as well as on the processing of measurement results and comparison with hygienic regulations and already measured values.
68

Effects of strain, stocking density and limited-time feeding on growth performance and carcass characteristics of broiler chickens

Ligaraba, Tshililo Joyce 11 February 2016 (has links)
Department of Animal Science / BSCAGR
69

The effects of dietary crude protein on fertility of broiler breeder males.

Waltsleben, Stephanie Lisa von. January 2010 (has links)
Fertility of Broiler Breeders (BBs) has been researched over many years with inconclusive findings. Genetic selection and improvements in growth traits have had negative effects on fertility of BB. One explanation is related to overweight birds, resulting in the inability of birds to copulate successfully, with no cloacal contact. The requirements of CP for egg production in BB females have been quantified, but there is less literature on how CP affects fertility in male BBs. The objective of this experiment was to investigate the effects of feeding BB males different dietary CP intakes (10.4, 12.4, 14.2, 17.8, 19.3 and 20.1 g CP/bird/day) on fertility in flocks with natural mating and in birds that were artificially inseminated (AI). Results showed that birds consuming 10.4 and 12.4 g CP/bird/day resulted in weight loss (between 24.9 and 23.6% and 26.5 and 22.4% below target BW) over the 29 weeks of the experimental period in both natural mating and individual pens respectively. Intakes of higher protein content (17.8- 20.1 g CP/bird/day) however resulted in BW gain over the experimental period. Hatch percentage across all CP intakes throughout the duration of the study was found to be high, ranging between 75- 100 and 80-95 % in AI and naturally mated birds respectively, and not affected by CP intakes. Similar results for predicted fertility using the methods published by Brillard & Antoine (1990) and Wishart (1997) were found; however Brillard & Antoine (1990) is more lenient requiring less outer perivitelline layer (OPVL) sperm/mm2 to pronounce an egg fertile. Improved fertility predictions could have been made by using examination of inner perivitelline layer (IVPL). There was a tendency for a superior response in predicted fertility from birds with a protein intake of 14.2 g CP/bird/day. This intake also least affected the BW of the male birds and thus 14.2 g CP/bird/day can be recommended for optimal BB male performance. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
70

Podnikatelský koncept zařízení lovecké turistiky - Plzeňský kraj / Business koncept of facilities of hunting tourism - Pilner region

ŠEFLOVÁ, Dana January 2012 (has links)
The general aim of my diploma thesis was to create a business concept of facilities of hunting tourism in the Pilsner region. Klatovské rybářství, a.s. was selected as a cooperative company, which deals with agricultural activities, especially fish and poultry breeding. The company operates some services of hunting tourism, but it is not the main field. The thesis will serve as a manual for "non-experts" who are interested in expanding their range of travel services. The resulting business concept will consequently be presented to the management of the company in order to demonstrate how the company can further develop. While writing this thesis I got several perspectives on the issue of hunting tourism in the area. The first view was provided by the existing clients of the company who filled in questionnaires which were designed to determine their interest in these services. In addition, three representatives were selected from age groups who were asked for ideas about how the device should look. Another view was obtained through an interview with the director of the company and the employee responsible for the current planning and management of hunting activities. Next view on the issue of hunting tourism, which should be independent, was provided by an employee of Infocentre Bor. Here it was revealed that hunting tourism is not popular with everyone and that it is a rather controversial topic. However, we can say that if done correctly and with concern for the countryside, it can bring many benefits to the given region. These include attracting visitors of other segments of the society, the development of the region, expansion of tourism services and expansion of cooperation between entrepreneurs. Last view was represented by my own experience that I gained during working participation in hunting tourism events. At the beginning of my diploma thesis I determined three working hypotheses. All available resources helped me to evaluate the present circumstances and I can confirm all three hypotheses. The general aim was to create a business concept of facilities of hunting tourism in the Pilsner region. I was able to realize the general aim thanks to the cooperation with the company and by means of utilizing all available information. Now the diploma thesis will be handed over to the management for consideration and possible implementation

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