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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.
31

Use of decision science to aid selection of genetically superior animals : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Palmerston North, New Zealand

Sherriff, Ryan Leith January 2010 (has links)
This thesis is concerned with a theoretical simulation model for pig breeding, as part of the ongoing search for the “perfect” genotype. The starting point is an additive model to investigate how accurately the classical, infinitesimal model predicts genetic gain for traits controlled by few loci and few alleles. This initial investigation demonstrates that the infinitesimal model is robust, providing that at least 15 loci are controlling a trait and there is symmetry in the allele distributions. A Genotype-Pig (GE-Pig) model is then developed to apply the additive effects of alleles on sub-phenotypic traits like maximum protein deposition, minimum lipid to protein content in the whole body, ad libitum digestible energy intake, energy for maintenance requirement and water content in the whole body. These parameters are then used in a nutrient partitioning simulation model to growth a pig and calculate traditional breeding traits such as average daily gain, feed conversion ratio, and backfat thickness for any combination of alleles. Three algorithms, Genetic Algorithm, Tabu Search, and Simulated Annealing, are used to investigate the GE-Pig model and find optimal combination of alleles for different dietary and selection objective situations. The two diets investigated were either of a low or high quality, and the three selection objectives used were, maximising average daily gain, minimizing feed conversion ratio, and minimizing back fat. A graphical method is developed for easy comparison of the genotypes. Of the algorithms, the Genetic Algorithm performed the best, followed by Tabu Search and finally Simulated Annealing. It is demonstrated that, in general, there is a different, single, optimum for any given selection objective and diet. However under the back fat selection objective, both diets produce the same optimal genotype. Also there are many similarities between the optima for the average daily gain and feed conversion ratio selection objectives. When the theoretical minimum number of generations of selection to the optima is considered, the feed conversion ratio selection objective is the quickest for a breeding program to achieve the optimal solutions, followed by back fat, then average daily gain. It is demonstrated that diet also has an effect on the theoretical number of generations. A Multiple selection objective, using relative economic values applied to the individual selection objectives, is also investigated. For both diets, the majority of the multiple selection objective solutions are in the vicinity of the feed conversion ratio optima, indicating that feed conversion ratio is the most prominent factor. It is also demonstrated that the optimal solution is most affected by the objective parameter weights under low diet conditions.
32

O BIODIGESTOR COMO ALTERNATIVA TECNOLÓGICA PARA TRATAMENTO DE DEJETOS SUÍNOS: UM ESTUDO DE CASO DO SISTEMA INTEGRADO DE PRODUÇÃO NA REGIÃO DAS MISSÕES DO ESTADO DO RIO GRANDE DO SUL / THE BIODIGESTER AS TECHNOLOGICAL ALTERNATIVE FOR THE TREATMENT OF SWINE MANURE PIGS A CASE STUDY OF THE INTEGRATED SYSTEM OF PRODUCTION IN THE REGION OF MISSIONS IN RIO GRANDE DO SUL

Machado, Rosane Bueno 30 September 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Swine breeding is an activity in constant growth in Brazil especially in the Southern regions of Brazil. Nowadays, this activity plays a very relevant role for Brazilian economy, generating employment and income for rural properties. With this in mind, several concerns arise regarding the environmental issue, since the waste resulting from this activity cause great damages to the environment if not treated properly. Based on the factors of this research, the use of the bio-digesters technology is proposed as an alternative for the treatment of the swine breeding waste. A field survey was used as a method, and it was clear that the breeders use some kind of waste treatment technique in their properties in order to ease the issue of environmental contamination. The results of this work show that the breeders are aware of the need for a proper way of dealing with waste and they consider the biodigester as an important piece of technology to be used in their properties. The use of the equipment is beneficial and ranges from pollution control, bio-gas production and bio-fertilizer. Moreover, it is stressed that from the moment the breeders acknowledge the importance of such products and start using them in their properties, there is a considerable cost reduction, increased productivity, and a larger value for money to the swine breeding property. / A suinocultura é uma atividade em constante crescimento no Brasil em especial nas regiões Sul do país. Atualmente, esta atividade assume um papel de grande relevância para a economia brasileira, gerando emprego e renda para as propriedades rurais. Frente a esse potencial de crescimento surgem diversas preocupações com a questão ambiental, tendo vista que os dejetos resultantes desta atividade provocam grande agressão ao meio ambiente se não forem tratados de maneira adequada. Baseado nestes fatores que esta pesquisa propõe o uso da tecnologia dos biodigestores como alternativa de tratamento dos dejetos gerados pela produção suinícola. O método utilizado foi à pesquisa de campo, onde se verificou, através da aplicação de questionários, se os produtores usam alguma técnica de tratamento de dejetos resultantes da produção suinícola em suas propriedades com objetivo de amenizar o problema da contaminação do meio ambiente. Os resultados deste trabalho demonstram que os produtores têm a consciência quanto á necessidade do destino correto dos dejetos e consideram o biodigestor como tecnologia importante que deve ser utilizada em suas propriedades. O uso do equipamento traz benefícios que vão além do controle da poluição, como a produção do biogás e do biofertilizante. Além disso, enfatiza-se que a partir do momento que os suinocultores reconhecem a importância destes produtos e começam a utilizá-los em suas propriedades há uma considerável redução de custos, aumento na produtividade, e uma maior agregação de valor a propriedade criadora de suíno.
33

Estudo da distribuição da temperatura em instalações para a criação de fêmeas suínas em fase de gestação com o uso da fluidodinâmica computacional (CFD) / The CFD technique for the study of the indoor distribution air temperature in pregnant sows facilities

Sabino, Luana Araujo, 1984- 02 June 2015 (has links)
Orientador: Daniella Jorge de Moura / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-27T21:38:28Z (GMT). No. of bitstreams: 1 Sabino_LuanaAraujo_D.pdf: 5594290 bytes, checksum: 53aedcae8886f70448b204ed245f3d66 (MD5) Previous issue date: 2015 / Resumo: Um dos principais problemas no interior de instalações de criação animal é o controle do ambiente por meio ventilação, sendo de grande importância para a qualidade aérea e conforto térmico de verão e inverno, principalmente em regiões de clima tropical. O uso de técnicas para o estudo do ambiente avança a cada dia em qualidade e precisão dos resultados. Uma das novas técnicas é a modelagem computacional que auxilia, de forma rápida, a solução de diversos problemas, mesmos os complexos, com baixo custo, em comparação com métodos experimentais. Sendo assim, o objetivo deste projeto será de validar um modelo computacional de Fluidodinâmica Computacional (Computational Fluid Dynamics ¿ sigla em inglês, CFD) com o uso da geoestatística e com o cálculo do erro da variável temperatura de bulbo seco, demonstrando que podem ser utilizadas diferentes metodologias para sua validação. Além disso objetivou-se estudar os efeitos de diferentes malhas no processamento e na qualidade dos resultados obtidos, apresentando ou sugerindo uma metodologia para estudos futuros / Abstract: In animal production, the major problem of animal facilities is the internal temperature control through ventilation systems. This is responsible for maintaining proper air quality and thermal comfort for the animals during the summer and winter conditions, especially in regions with tropical climate. The environment at studies using new techniques, such as Computational Fluid Dynamics (CFD) has became more popular due to the quality and precision of the results. In this respect, the computational modelling is a powerful tool to help in the solution of several problems, including complex ones, with reduced cost when compared with experimental methods. Thus, the goal of this study is to validate a CFD computational model with geostatistics technique and the estimation of the error of the dry bulb temperature prediction by the model in order to validate the CFD model. It also, analyses the effect of different meshing methods in the results, developing thus way a methodology for future researches / Doutorado / Construções Rurais e Ambiencia / Doutora em Engenharia
34

Effects of two levels of dietary energy supplementation and rearing systems on growth and carcass characteristics of grower pigs

Makgothi, Onkabetswe Gogakgamatsamang January 2012 (has links)
Thesis (M. Tech. Agriculture) -- Central University of Technology, Free state, 2012 / The eight-week study was conducted to evaluate the effects of rearing system (indoor vs. outdoor) and energy level on digestibility, growth performance and on the carcass characteristics and visceral organs of pigs. A total of 48 Large Whites (LW) X Landrace (LR) male grower pigs were randomly selected at average weights of 27 ± 4.6.kg and divided into two equal groups that were either raised indoors or outdoors. Within each rearing system, half the pigs were fed on a diet formulated to contain either a normal energy level (14 MJ DE/kg) or high energy level (16.1 MJ DE/kg) resulting in a 2 X 2 factorial design. The pigs were fed ad libitum and water was freely available. Pigs were housed in pairs and each indoor and outdoor pig was offered a space allowance of 0.51 and 13.5 m2 respectively. Indoor pigs were raised in a temperature controlled house consisting of a concrete floor pen while outdoor pigs were on a pasture that predominantly consisted of Kikuyu. Movable gates were used to construct outdoor camps and empty feed bags were used to construct a shade for use as shelter. Faecal collection for digestibility determination took place during week 7 while the growth performance trial was still in progress. Chromium oxide was used to evaluate digestibility and faeces were grabbed before they fell to the ground and sampled. With the exception of ether extracts (EE), the digestibilities of crude protein (CP), digestible energy (DE), crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF) and organic matter (OM) were reduced (P <0.05) by rearing pigs outdoors. EE followed the same trend. Feeding the high energy (HE) diet significantly (P >0.05) improved the digestibilities of all the nutrients except for CP. There were no significant interactions (P>0.05) between rearing system and diet for the digestibility of nutrients. Daily gains were similar (P >0.05) between indoor and outdoor pigs. Daily feed intakes and conversions were significantly (P <0.05) lower in indoor pigs. There were no significant (P >0.05) differences between the daily gains and feed conversions of pigs fed either the normal energy (NE) or the HE diet. Indoor pigs fed the HE diet had lower (P < 0.05) feed intakes compared to pigs on the other treatments. In general, average daily feed intakes (ADFI) of the HE fed pigs were significantly (P <0.05) lower than those of the NE fed pigs. The carcass measurements of the indoor and outdoor pigs were similar. The gastro-intestinal tract (GIT) and the liver weights of the outdoor reared pigs were significantly (P <0.05) heavier than those of the indoor reared pigs. Feeding the HE diet led to significantly (P <0.05) higher carcass weights and dressing percentages. Interactive effects (P <0.05) of diet and rearing system were found for lean meat percentage (Lean P) and eye muscle area (EMA). Indoor pigs fed on the NE diet had higher Lean P and EMA while an opposite effect was obtained in the outdoor system. The liver of the NE diet fed pigs was significantly (P < 0.05) heavier than that of the pigs fed the HE diet. It can be concluded that with regard to growth performance and carcass characteristics, the NE and HE diets are respectively best suited for the indoor and outdoor rearing of pigs.
35

Development of cryopreservation strategies for improved reproductive competence in South Africa pig genotypes

Bailekae, Masenya Matshidiso January 2012 (has links)
Thesis (M. Tech. Agriculture) -- Central University of Technology, Free state, 2012 / Frozen-thawed boar sperm has the potential to impact the future of the swine industry. The objectives of the study were to characterise semen of Kolbroek and Large White boars, find a suitable holding temperature and extender, determine the effect of breed and pregnancy rate following artificial insemination by frozen-thawed boar semen. A total of eight boars and 33 sows were used in this study. The 120 ejaculates were collected from each individual Kolbroek and Large White boars with the gloved-hand technique. Macroscopic and microscopic sperm characteristics were recorded. The bodyweight of Kolbroek (154.7 kg) was significantly lower compared to Large White (189.9 kg) boar. However, no significant differences were observed in Kolbroek and Large White boar semen volume (140 and 170 ml), sperm concentration (0.727 and 0.761 x 109 sperm/ml), and total sperm motility (95 and 91%). A positive correlation existed between bodyweight and semen volume of Kolbroek (r= 0.22) and Large White (r= 0.26). Conversely, the bodyweight of Large White was positively correlated to sperm concentration of Large White (r= 0.37) but negatively correlated to Kolbroek (r= -0.66). Storage time and temperature did not affect Large White boar sperm motility rate. However, Kolbroek sperm total motility rate (61.0%) was affected at 25°C after 24 hours. The highest total sperm motility rate was observed for semen diluted with Tris-based extender (74.1%) in Kolbroek boars at 48 hours of storage. Large White boar semen diluted with BTS (62.9%), Kobidil+ (69.3%) and Tris (65.1%) showed significantly higher sperm motility rate at 48 hours of storage, compared to Citrate (27.6%) extender. Cryopreservation significantly reduced sperm motility rate for Kolbroek (30.2%) and Large White (24.0%) boars. However, a high pregnancy rate was recorded in both sows of inseminated with raw diluted (100% vs. 81.3%) and frozen-thawed (50% vs. 50%) semen of Kolbroek and Large White boars. In conclusion, the bodyweight of Kolbroek and Large White boar was positively correlated with ejaculated semen volume. Kolbroek and Large White boar sperm stored at 18°C for 24 hours maintained the acceptable sperm motility rate. Kolbroek boar semen diluted with Tris-based extender maintained high sperm motility rate. Cryopreservation significantly reduced sperm motility rate regardless of breed; however, pregnancy rate from frozen-thawed semen was high for Kolbroek (50%) and Large White (50%) even though the frozen-thawed fertility was low.
36

Effect of advanced reproductive technologies on smallholders' pig productivity in Gauteng Province

Matabane, Matshidiso Bailekae January 2018 (has links)
Thesis (Ph.D. (Animal Production)) --University of Limpopo, 2018 / Pigs are of high economic importance, especially among the smallholder pig farmers as they contribute to human nutrition, food security, poverty alleviation, enhanced livelihood and creation of employment for the rural community. However, reproductive inefficiency is the main limiting factor due to inaccessibility to superior germplasm. Therefore, advances in reproductive technologies such as oestrus synchronization and artificial insemination (AI) offers unprecedented opportunities for livestock improvement for smallholder pig farmers. The first objective determined the status of pig productivity in smallholder farms of Gauteng Province prior to the introduction of advanced reproductive technologies (ARTs). The population was divided into four strata, namely West Rand, Ekurhuleni, Tshwane and Sedibeng district municipalities. A proportional stratified random sampling procedure was used to select 71 smallholder pig farmers with the assistance of extension officers from Gauteng Department of Agriculture and Rural Development (GDARD). The majority of the respondents were males (67%) and were above 50 years of age (67%), whilst 56% of the respondents had high school education. Majority of the respondents privately owned the farms (62%) and the farm infrastructure had facilities with low cost housing and modern facilities. Additionally, 47% of the respondents fed their pigs with feed swill. A large proportion of the respondents did not vaccinate their pigs (81%). Majority of respondents did not identify their pig herds (63%). Interestingly, majority of the respondents did not have breeding boars (73%) and sold their pigs at auctions (70%). The second objective determined semen characteristics evaluated by a Computer Aided Sperm Analyser® (CASA®) as a measure of boar fertility to be used for artificial insemination (AI). Sixteen ejaculates were collected from three Large White boars that are routinely used for semen collection purposes using the gloved-hand technique. The semen was extended with a commercial semen extender; Beltsville Thawing Solution, and the AI dose used consisted of 80mL semen sample (3×109 spermatozoa/mL). Aliquots of diluted semen were evaluated for spermatozoa motility using CASA®. Spermatozoa viability was evaluated using Synthetic Binding CD-14 (SYBR+)/Propidium Iodide (PI-), whereas spermatozoa morphology was evaluated using Eosin Nigrosin stain. The average semen volume, concentration and pH were 210 mL, 264.8 x 106 spermatozoa/mL and 7.1, respectively. The average values for total spermatozoa motility was 95.1%, ranging from 82.7 and 98.5%. However, XIX there were lower values found for progressive spermatozoa motility, ranging from 13.6 to 39.0%. The mean values for morphologically normal spermatozoa ranged from 47.8-60.9% and live spermatozoa ranged from 71.8-77.7%. The third objective determined sow fertility following AI at smallholder farms A total of 73 multiparous sows were artificially inseminated. Conception rates, farrowing rates, litter size and number born alive were recorded. The average conception and farrowing rates were 78.1 and 57.5%, respectively. Furthermore, AI resulted in acceptable fecundity (i.e., 11.8 litter size and 10.0 number of piglets born alive). The fourth objective determined the relationship between spermatozoa quality characteristics and sow fertility at smallholder farms in Gauteng Province. Of all fertility characteristics studied, conception rate was significantly related to total spermatozoa motility rate (r= 0.37, P<0.01), progressive motility (r= 0.31, P<0.01) and rapid motility (r= 0.40, P<0.01), although relatively low. There was a low negative relationship between spermatozoa morphological characteristics and fertility (P>0.05). The fifth objective determined the pre-weaning growth performance of piglets born following AI at smallholder farms of Gauteng province. Individual piglets were weighed using an electronic weighing scale. Litter size, number of piglets born alive, number of piglets weaned, the average piglet birth weight and average piglet weaned weight were recorded. The average litter size was 11.8 ± 0.2. The average birth weight and weaning weights were 1.9 and 6.2 kg, respectively. No significant differences were found between male and female piglets for all the growth performance characteristics. Piglets born during winter had a significantly higher (P<0.05) birth and weaning weight as compared to autumn and summer months. Season had a significant effect on birth and weaning weight (P<0.01). However, sex of piglets had no effect on all the characteristics recorded (P>0.05). The interaction between sex and season was only observed on the total number of weaned piglets (P<0.01). A highly significant positive correlation was found between litter size and number of piglets born alive (r= 0.86) and total number of piglets weaned (r= 0.50). A highly significant correlation was found between total number of piglets born alive and total number of piglets weaned (r= 0.55). In conclusion, the study demonstrated the potential benefit of adopting AI technology under smallholder production systems to disseminate superior genetic material to smallholder pig farmers in Gauteng Province. The total spermatozoa motility, progressive and rapid spermatozoa motility were the only spermatozoa motility characteristics significantly correlated XX with conception rate. Conversely, litter size and number born alive were not correlated with CASA® spermatozoa motility attributes. No relationships existed between spermatozoa morphological characteristics and fertility. The sex ratio percentage of piglets born following AI was 52:48% (females: males). The number of piglets born alive was 10.2 and 9.5 for number piglets weaned. Season influenced birth to weaning weight. However, sex had no significant influence at birth and weaning weight. Litter size affects the number of piglets born alive and weaned. The study showed that the introduction of advanced reproductive technologies improved productivity of pigs at smallholder pig farms in Gauteng Province. / Gauteng Department of Agriculture and Rural Development (GDARD) and Southern African Science Service Centre for Climate Change and Adaptive Land Management (SASSCAL
37

The untold story of the pig farming sector in rural KwaZulu-Natal : a case study of Uthukela District

Gcumisa, Sibongiseni Thokozani 06 1900 (has links)
This study was done in the rural areas of uThukela District in KwaZulu-Natal. The objectives were to determine pig production and management practices used by farmers in rearing pigs in rural areas; to establish the role of pigs in social and economic lives of the people; and to characterize and determine constrains and opportunities of pig farming in rural areas. A farming systems approach was used in conjunction with a cross-sectional survey method using a structured questionnaire in face-to-face interviews with farmers for the collection of data. The study involved 4 local rural municipalities with a population of 4205 people who owned 2555 pigs. The sample size was 533 pig farmers/respondents. The data included the demographic characteristics of pig farmers, pig production and management practices, the role of pigs in both the social and economic lives of people and the constraints and opportunities of pig farming. The data were analyzed to determine simple means and frequencies. The results showed that 20% of pigs were reared in intensive systems and 80% in extensive systems in the district. Each village owned an average of 5 pigs. There were more female respondents (60%) than males, and also female respondents owned more (65%) pigs than males. Most of respondents (99%) were Zulu speaking people and only 1% was from other cultural groups. Majority of the respondents (74%) were unemployed, 16% were pensioners and only 10% were employed. Those who were employed kept more pigs than the other groups. Over one third of the respondents had primary (34.5%) and secondary (35.3%) education; and 2.7% had college education, while 27.5% had no formal education at all. Sixty-two percent of the older respondents between the age of 46 and 65 years kept more pigs than younger farmers. The collective incomes of the communities from salaries, pensions, and sales of livestock and crops per annum were substantial. The average land size per household ranged from 0.01 ha to 56 ha. Male respondents owned more land (1.68 ha) than female respondents (0.96 ha). Similarly, employed people owned more land (2.49 ha) than pensioners (1.26 ha) and the unemployed people (1.04 ha). Respondents kept other livestock species such as cattle, sheep, goats and chickens. Ninety percent of households kept chickens in addition to cattle (53%) and goats (49.3%). They also grew crops such as maize, potatoes, vegetables (cabbage, spinach, tomatoes, carrots, beetroots and onions) and fruits (peaches, apples and grapes). They kept pigs for home consumption (63%), source of income (33%), source of manure (3%) and for other reasons (1%). More employed people (68%) sold pigs for extra income, while 91% pensioners and 81% unemployed people used pigs for home consumption. Marketing channels included pension pay points, abattoirs, butcheries and neighbourhoods. Abattoir sales accounted for 10% and the most common venues were Amblecyte (40%) and Cato Ridge (27%). Selling of pigs occurred throughout the year, with the peak in winter (May/July). Majority of farmers (59%) used their own transport to deliver pigs to the selling points or they used contractors (41%). Pigs were sold at the age of 5 to 18 months old. Farmers sold live pigs and pork to the communities. Some farmers sold live pigs only, while others sold pork only or both pork and live pigs. Religion and culture had little influence on pig farming. Most farmers (88%) had no religious or cultural influences, while 7% were influenced by religion and 1% was influenced by culture. The most preferred meat among the communities was chicken meat, followed by beef, pork, mutton and chevon. Half of the respondents had >6 years of experience in pig farming, 34.9% had 2 – 5 years of experience and 14.8% were beginners. The breeds of pigs kept in the district included indigenous breeds, Large White, Landrace, Duroc and crosses of indigenous breeds with Large White and Landrace. Farmers bought breeding stock within their communities or they selected breeding stock from their own herds. Very few farmers have ever received any type of training in pig farming. The training was provided by the KZN Provincial Government, Zakhe Agricultural College and private farms. The training took 2-3 days of workshops, 2-3 weeks of short courses or 3-6 months of hands-on training on private farms. The training improved the performance of sows within the communities. Only 41% of farmers practised controlled stock breeding, which improved the farrowing rate and litter size. About one third (32%) of farmers bred their gilts at 6 – 8 months, while 21.2% bred them at 8-12 months, and 29% bred them after 12 months. The farrowing rate of indigenous sows was one litter per annum compared with the majority of Landrace and Duroc sows that farrowed twice a year. Some farmers (28%) reported that they routinely observed farrowing, while 72% of them said they never knew when the sows farrowed until they saw sows and new litters coming back to their pens after grazing in the veld. The litter sizes varied from ≤ 7 to ≥ 10. Half of the indigenous sows farrowed ≤ 7 piglets per litter, while 41% had 8-10 piglets; compared with 49% Large White and 44% Duroc that farrowed 8-10 and ≥ 10 per litter, respectively. Majority of farmers (66.1%) did not wean their piglets at all, which was associated with low farrowing rate. However, farmers who sold weaners for income weaned their piglets between 3 weeks and 3 months. This was associated with higher farrowing rate of sows. Piglet mortality was mainly due to worm infestation (26%), loss of hair (13%), lice and mange infestation (16.4%) and diarrhoea (5.6%). Despite that only 10% of farmers consulted the local Department of Veterinary Services. Some farmers (44.2%) said that they did not know that they could make use of Veterinary services, and 28% of them said it was a waste of time. Majority of farmers (80%) used home kitchen swill and brewer’s grains to feed their pigs. Only 16% of farmers bought commercial feeds and 2% fed them on maize grains and vegetables. Commercial feeds were bought from Farm Save (48%), Afgri (19%) and Epol (7%). Some farmers (65.4%) weighed feed before feeding, while 35% did not weigh feed at all. Water was provided at feeding time, ad libitum or several times a day. Farmers disposed of carcasses by eating them, feeding to their dogs, or throwing them away. Over half of the farmers (52%) did not take carcasses for post mortem, while 26% did not know that they could send carcasses for post mortem and 20% said they could not afford the cost. The study concluded that pigs have a vital social and economic role in the lives of the rural people of KZN for income generation and household consumption. The main constraints are wide spread poverty and lack of management skills in pig production, nutrition, health,housing and management. Government intervention is necessary to help farmers to improve pig production and management as a means of poverty alleviation and household food security. / Agriculture and  Animal Health / M.Sc. (Agriculture)
38

Comportamento bioclimático de matrizes suínas em gestação e o uso de sistemas inteligentes na caracterização do ambiente produtivo: suinocultura de precisão / Bioclimatic behavior of pregnant sows and use of intelligent systems for production environment characterization: precision swine breeding

Pandorfi, Héliton 01 August 2005 (has links)
O objetivo geral desta pesquisa consiste na avaliação de diferentes sistemas de alojamento para matrizes gestantes, visando caracterizar aspectos quantitativos e qualitativos do ambiente e as variáveis que influenciam o sistema de produção, determinando as condições favoráveis ao melhor desempenho animal, baseada nas respostas ao ambiente de criação. O experimento foi realizado no período compreendido entre 04/01 e 11/03/2005, em uma propriedade de produção industrial de suínos, localizada no município de Elias Fausto, estado de São Paulo. A pesquisa foi desenvolvida no setor de gestação, com 24 matrizes primíparas, 12 fêmeas alojadas em baias individuais (T1) e 12 animais em baias coletivas (T2) e posteriormente na maternidade, onde foram quantificados os índices de produção dos leitões provenientes do estudo. O trabalho foi dividido basicamente em três etapas, em função da forma de avaliação dos dados: análise bioclimática; análise dos sistemas de produção; avaliação de sistemas inteligentes disponíveis, lógica fuzzy e redes neurais artificiais (RNAs) para o estudo de padrões de conforto térmico ambiental e predição dos índices zootécnicos, peso no nascimento e número de leitões mumificados, com base nos dados de temperatura ambiente e taxa respiratória das matrizes. A avaliação bioclimática foi realizada por meio do registro das variáveis meteorológicas (temperatura ambiente, umidade do ar, temperatura de globo negro e velocidade do vento) e ambientais (concentração de gases), na sala de gestação e no ambiente externo, possibilitando a caracterização da eficiência térmica, pelos índices de temperatura de globo e umidade (ITGU) e entalpia específica (h) e da condição de salubridade da instalação. A análise do sistema de produção teve, como variáveis respostas aos tratamentos avaliados, as relações comportamentais, os parâmetros fisiológicos e os índices zootécnicos. O delineamento experimental foi em blocos casualizados, com dois tratamentos e 67 blocos, e as médias, comparadas pelo teste de Tukey. As variáveis meteorológicas e ambientais apontam o sistema de confinamento em baias coletivas como aquele que permitu melhor condicionamento térmico natural às matrizes em gestação. Com relação à concentração de gases, os teores médios não superaram as concentrações consideradas críticas para as matrizes. Os parâmetros fisiológicos e os índices zootécnicos apresentaram valores mais adequados para o T2, assim como seu reflexo no desempenho da parição dos leitões. A avaliação comportamental, realizada pelo monitoramento por meio do registro de imagens de vídeo, apontou menor incidência de comportamentos resultantes do estresse ambiental, estereotipias e interações agressivas referentes ao estabelecimento de uma organização social no T2 comparativamente ao T1. O uso da teoria dos conjuntos fuzzy permitiu que se fizesse uma alusão entre os dados resultantes do trabalho experimental com os estabelecidos pela literatura, por intermédio de uma base de regras estabelecidas, para a determinação do conforto ambiental aplicado a matrizes na fase de gestação. O sucesso das redes neurais esteve diretamente relacionado com a sua alta versatilidade, permitindo as aproximações propostas neste trabalho para a predição dos índices zootécnicos. / This study evaluated different housing systems for pregnant sows aiming to describe quantitative and qualitative aspects of environment, as well as variables that have effect on production system. The optimal conditions for animal performance improvement have been determined analyzing behavioral data took in breeding environment. Trial was carried out from january 4th to march 11th 2005 in a farm specialized in industrial production of pork, located in Elias Fausto City, São Paulo State. In gestation facility 24 gilts were allocated:12 in individual stalls (T1) and 12 in group housing (T2). Further, in farrowing housing, piglets were evaluated in relation to their production variables. Basicaly, this study was divided in three steps in function of the way chose for data analysis: bioclimatic analysis; analysis of the production systems; evaluation of the available intelligent systems: fuzzy logic and artificial neural nets (ANNs) for studing environmental thermal confort patterns and prediction of produtive indexes, birth weights and number of mummifed piglets, based on data of environmental temperature and sow respiratory rates. Bioclimatic evaluation was realized by registering metheorological variables (environmental temperature, air humidity, dark globe temperature and wind velocity) and environmental variables (concentration of gases) inside of parturition room and in external environment, which permitted to characterize thermal efficiency by indexes of globe temperature and humidity (IGTH) and specific enthalpy (h) and salubrious condition of facility. The analysis of production system had as variables the answers to treatments, the behavioral relationships, physiological parameters and productive indexes. Experimental design was randomized blocks with two treatments and 67 blocks. Means were compared by Tukey test. Metheorological and environmental variables indicated the confinement system in group-houses as that permitted the better natural thermal monitoring for pregnant gilts. In relation to concentration of gases, mean levels did not exceed the concentrations considered limitating for sows. Physiological parameters and productive indexes were more adequate in T2, which reflected in performance during parturition. Behavior evaluation, realized by image monitoring using video cameras, showed lower incidence of behaviors related to environmental stress, stereotypies and agressive interactions caused by social organization establishment within group-housing system. The fuzzy set theory permitted to compare experimental data with those reported in cientific papers through rules created for proportionating well-fare of sows during gestation period. The success of neural nets was directly related to it high versatility, wich allowed aproximating productive indexes for predictions proposed in this work.
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Comportamento bioclimático de matrizes suínas em gestação e o uso de sistemas inteligentes na caracterização do ambiente produtivo: suinocultura de precisão / Bioclimatic behavior of pregnant sows and use of intelligent systems for production environment characterization: precision swine breeding

Héliton Pandorfi 01 August 2005 (has links)
O objetivo geral desta pesquisa consiste na avaliação de diferentes sistemas de alojamento para matrizes gestantes, visando caracterizar aspectos quantitativos e qualitativos do ambiente e as variáveis que influenciam o sistema de produção, determinando as condições favoráveis ao melhor desempenho animal, baseada nas respostas ao ambiente de criação. O experimento foi realizado no período compreendido entre 04/01 e 11/03/2005, em uma propriedade de produção industrial de suínos, localizada no município de Elias Fausto, estado de São Paulo. A pesquisa foi desenvolvida no setor de gestação, com 24 matrizes primíparas, 12 fêmeas alojadas em baias individuais (T1) e 12 animais em baias coletivas (T2) e posteriormente na maternidade, onde foram quantificados os índices de produção dos leitões provenientes do estudo. O trabalho foi dividido basicamente em três etapas, em função da forma de avaliação dos dados: análise bioclimática; análise dos sistemas de produção; avaliação de sistemas inteligentes disponíveis, lógica fuzzy e redes neurais artificiais (RNAs) para o estudo de padrões de conforto térmico ambiental e predição dos índices zootécnicos, peso no nascimento e número de leitões mumificados, com base nos dados de temperatura ambiente e taxa respiratória das matrizes. A avaliação bioclimática foi realizada por meio do registro das variáveis meteorológicas (temperatura ambiente, umidade do ar, temperatura de globo negro e velocidade do vento) e ambientais (concentração de gases), na sala de gestação e no ambiente externo, possibilitando a caracterização da eficiência térmica, pelos índices de temperatura de globo e umidade (ITGU) e entalpia específica (h) e da condição de salubridade da instalação. A análise do sistema de produção teve, como variáveis respostas aos tratamentos avaliados, as relações comportamentais, os parâmetros fisiológicos e os índices zootécnicos. O delineamento experimental foi em blocos casualizados, com dois tratamentos e 67 blocos, e as médias, comparadas pelo teste de Tukey. As variáveis meteorológicas e ambientais apontam o sistema de confinamento em baias coletivas como aquele que permitu melhor condicionamento térmico natural às matrizes em gestação. Com relação à concentração de gases, os teores médios não superaram as concentrações consideradas críticas para as matrizes. Os parâmetros fisiológicos e os índices zootécnicos apresentaram valores mais adequados para o T2, assim como seu reflexo no desempenho da parição dos leitões. A avaliação comportamental, realizada pelo monitoramento por meio do registro de imagens de vídeo, apontou menor incidência de comportamentos resultantes do estresse ambiental, estereotipias e interações agressivas referentes ao estabelecimento de uma organização social no T2 comparativamente ao T1. O uso da teoria dos conjuntos fuzzy permitiu que se fizesse uma alusão entre os dados resultantes do trabalho experimental com os estabelecidos pela literatura, por intermédio de uma base de regras estabelecidas, para a determinação do conforto ambiental aplicado a matrizes na fase de gestação. O sucesso das redes neurais esteve diretamente relacionado com a sua alta versatilidade, permitindo as aproximações propostas neste trabalho para a predição dos índices zootécnicos. / This study evaluated different housing systems for pregnant sows aiming to describe quantitative and qualitative aspects of environment, as well as variables that have effect on production system. The optimal conditions for animal performance improvement have been determined analyzing behavioral data took in breeding environment. Trial was carried out from january 4th to march 11th 2005 in a farm specialized in industrial production of pork, located in Elias Fausto City, São Paulo State. In gestation facility 24 gilts were allocated:12 in individual stalls (T1) and 12 in group housing (T2). Further, in farrowing housing, piglets were evaluated in relation to their production variables. Basicaly, this study was divided in three steps in function of the way chose for data analysis: bioclimatic analysis; analysis of the production systems; evaluation of the available intelligent systems: fuzzy logic and artificial neural nets (ANNs) for studing environmental thermal confort patterns and prediction of produtive indexes, birth weights and number of mummifed piglets, based on data of environmental temperature and sow respiratory rates. Bioclimatic evaluation was realized by registering metheorological variables (environmental temperature, air humidity, dark globe temperature and wind velocity) and environmental variables (concentration of gases) inside of parturition room and in external environment, which permitted to characterize thermal efficiency by indexes of globe temperature and humidity (IGTH) and specific enthalpy (h) and salubrious condition of facility. The analysis of production system had as variables the answers to treatments, the behavioral relationships, physiological parameters and productive indexes. Experimental design was randomized blocks with two treatments and 67 blocks. Means were compared by Tukey test. Metheorological and environmental variables indicated the confinement system in group-houses as that permitted the better natural thermal monitoring for pregnant gilts. In relation to concentration of gases, mean levels did not exceed the concentrations considered limitating for sows. Physiological parameters and productive indexes were more adequate in T2, which reflected in performance during parturition. Behavior evaluation, realized by image monitoring using video cameras, showed lower incidence of behaviors related to environmental stress, stereotypies and agressive interactions caused by social organization establishment within group-housing system. The fuzzy set theory permitted to compare experimental data with those reported in cientific papers through rules created for proportionating well-fare of sows during gestation period. The success of neural nets was directly related to it high versatility, wich allowed aproximating productive indexes for predictions proposed in this work.
40

Climate change adaptation and economic valuation of local pig genetic resources in communal production systems of South Africa

Madzimure, James January 2011 (has links)
The broad objective of the study was to determine the economic value of local pigs in marketand subsistence-oriented production systems in communal areas of Southern Africa. Data were collected from 288 households to investigate farmer perceptions, effects on pig production and handling of disease outbreaks such as classical swine fever (CSF) in market- and subsistenceoriented production systems. The utilisation of local pigs in these market- and subsistenceoriented production systems in improving people‟s welfare was evaluated. Climate change was identified by farmers in these production systems as a major constraint to pig production hence an experiment was carried out in the hottest season to determine diurnal heat-related physiological and behavioural responses in Large White (LW) and South African local pigs. The same genotypes were used to determine effects of diurnal heat-related stress on their growth performance. Choice experiment was done to determine farmer preferences for local pig traits and implicit prices for these traits in CSF-affected and unaffected areas that were under subsistence- and market-oriented production systems. In this experiment, the importance of heat tolerance was assessed relative to other productive and climate change adaptation traits. Significantly more pigs were culled in the CSF-affected areas that were market-oriented (8.0 ± 1.76) than subsistence-oriented (4.1 ± 1.00) production system. The risk of parasites and disease challenges was high in subsistence-oriented production system and coastal areas. In both production systems, CSF was perceived as destructive since the culling of pigs affected pork availability and income generation. The high risk of disease outbreaks and threat of climate change caused farmers in subsistence-oriented production system to select local pigs for their adaptive traits while those in the market-oriented production system focused on productive imported pigs. Farmers (83 %) indicated that they wanted pig genotypes that were adapted to climate change effects such as hot conditions. Local pigs were found to have superior heat tolerance over LW pigs (P < 0.05) in terms of lower heart rate and skin surface temperature. Frequency per day and duration for behavioural heat loss activities such as wallowing, sleeping in a prostrate posture and sprawling in slurry were also lower (P < 0.05) for local than LW pigs. The superiority of heat tolerance of local over LW pigs was further confirmed by their uncompromised growth performance under high diurnal temperatures. The Pearson‟s product moment correlation coefficient between temperature and feed conversion ratio for LW pigs was strongly positive (r = 0.50; P < 0.001) unlike the weak and positive correlation for local pigs (r = 0.20; P < 0.05). There was a quadratic relationship between temperature and average daily gain (ADG) for both pig genotypes. The regression coefficients for ADG were higher (P < 0.001) for LW than local pigs. It was concluded that at high ambient temperatures, performance of local pigs was less compromised than for LW pigs. Although local pigs were found to be heat tolerant, results of choice experiment showed that this trait was not selected for relative to other traits. Keeping pigs that required bought-in feeds, fell sick often and produced low pork quality (eating quality based on farmer perceptions) negatively affected farmers‟ livelihoods more in subsistence- than market-oriented production system. Farmers in market-oriented production system derived more benefit from productive traits such as heavier slaughter weights and large litter size than subsistence-oriented farmers. Under the subsistence-oriented production system, farmers in CSF-affected areas placed high prices on adaptive traits than the unaffected areas. Subsistence-oriented farmers who were affected by CSF wanted a total compensation price of R10 944.00 (USD1563.43) for keeping a pig genotype with unfavourable traits when compared to R4235.00 (USD605.00) for their CSF-unaffected counterparts. Implicit prices for traits could not be determined for market-oriented production system. It was concluded that farmers in CSFaffected areas placed high economic values on pig traits than farmers from the CSF-unaffected areas. The findings suggest that adapted local pigs can be promoted in subsistence-oriented production systems while productive imported pigs and their crosses with local pigs can be kept in market-oriented production systems.

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