Data from the Quebec swine breeding program (1980 to 2001) were used to estimate genetic parameters for longevity and to evaluate the contribution of non-genetic factors. After data verifications, there were 28,377 Yorkshire, 30,123 Landrace and 7,830 Duroc sows with records of herd life. The program 'The Survival Kit V3.12' (Ducrocq and Solkner, 2001) was used to estimate heritability separately within each breed, using a Cox proportional hazard model. The time-independent fixed effects of age at first service and of the combinations of herd with year of birth, estimated breeding value (EBV) backfat, EBV age to 100 kilograms and EBV litter size were included. The effects of number of piglets born, number of piglets weaned, crossbreeding at insemination, stage of sow (farrowing, weaning or heat) and their combination with parity were treated as fixed time-dependent variables whereas herd by year was treated as random time-dependent variable. The random effect of sire using sire relationships back two generations was considered as the source of genetic variation. Length of productive life (longevity) was defined as the number of days from first service until culling.

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A tese analisa o segmento industrial de insumos para a criação de suínos, um locus importante de inovações que transformam os produtos e os processos, afetam o desempenho dos animais e a qualidade da carne e, concomitantemente, sofrem e desencadeiam e mudanças institucionais no mercado e organizacionais nas firmas ligadas à produção de carne suína. As características e as mudanças do padrão de inovação dos insumos para a criação de suínos dos grupos industriais de medicamentos veterinários, nutrição animal e genética suína são estudados, focalizando especificamente a dinâmica da(s) trajetória(s) tecnológica(s) das firmas de genética suína, suas relações institucionais e organizacionais com o sistema de mercado e com o sistema tecnológico de carne suína. Considerando que o tempo é fator importante nos processos, propõe-se um modelo para a avaliação conjunta das mudanças produtivas e qualitativas nos suínos e em sua carne, permitindo inclusive a prospecção ordenada de tendências. O modelo é construído a partir da lógica fuzzy. A melhor compreensão da dinâmica inovativa e a análise de tendências de ação das firmas insumidoras auxiliam a formulação de sugestões para as políticas industrial e de fomento à inovação, à pesquisa e ao desenvolvimento tecnológico. / The present doctoral dissertation analyses the industrial segment of inputs for swine breeding, an important locus of innovations that transform the products and the processes, affects the animal development and the pork quality and, at the same time, provoke and are affected by institutional changes in the market and in the firms` structure organization linked to the pork production. The characteristics and the changes in the innovation standards of the inputs for swine breeding in the industrial groups of veterinary medicines, animal nutrition and swine genetics are studied, focusing specifically on the swine genetics firms technological(s) trajectory(ies) dynamics, on its institutional and organizational relations with the pork market system and with the pork technological system. As the time factor has a great importance throughout the process, the present dissertation also has the aim of proposing a model to evaluate productive and qualitative changes simultaneiously in the swine and in the pork, allowing an ordered projection of tendencies. This model is built using fuzzy logic.A better understanding of the innovative dynamics and an analysis of the behaviour of tendencies on the part of the firms dealing with raising of swine up to the final meat process help to suggest industrial, innovation and research, and technological development policies.

A tese analisa o segmento industrial de insumos para a criação de suínos, um locus importante de inovações que transformam os produtos e os processos, afetam o desempenho dos animais e a qualidade da carne e, concomitantemente, sofrem e desencadeiam e mudanças institucionais no mercado e organizacionais nas firmas ligadas à produção de carne suína. As características e as mudanças do padrão de inovação dos insumos para a criação de suínos dos grupos industriais de medicamentos veterinários, nutrição animal e genética suína são estudados, focalizando especificamente a dinâmica da(s) trajetória(s) tecnológica(s) das firmas de genética suína, suas relações institucionais e organizacionais com o sistema de mercado e com o sistema tecnológico de carne suína. Considerando que o tempo é fator importante nos processos, propõe-se um modelo para a avaliação conjunta das mudanças produtivas e qualitativas nos suínos e em sua carne, permitindo inclusive a prospecção ordenada de tendências. O modelo é construído a partir da lógica fuzzy. A melhor compreensão da dinâmica inovativa e a análise de tendências de ação das firmas insumidoras auxiliam a formulação de sugestões para as políticas industrial e de fomento à inovação, à pesquisa e ao desenvolvimento tecnológico. / The present doctoral dissertation analyses the industrial segment of inputs for swine breeding, an important locus of innovations that transform the products and the processes, affects the animal development and the pork quality and, at the same time, provoke and are affected by institutional changes in the market and in the firms` structure organization linked to the pork production. The characteristics and the changes in the innovation standards of the inputs for swine breeding in the industrial groups of veterinary medicines, animal nutrition and swine genetics are studied, focusing specifically on the swine genetics firms technological(s) trajectory(ies) dynamics, on its institutional and organizational relations with the pork market system and with the pork technological system. As the time factor has a great importance throughout the process, the present dissertation also has the aim of proposing a model to evaluate productive and qualitative changes simultaneiously in the swine and in the pork, allowing an ordered projection of tendencies. This model is built using fuzzy logic.A better understanding of the innovative dynamics and an analysis of the behaviour of tendencies on the part of the firms dealing with raising of swine up to the final meat process help to suggest industrial, innovation and research, and technological development policies.

A pig genetic resources study was conducted in five municipalities of Sekhukhune with the aim of characterising pig genetic resources in communal farming systems. A total of 52 pig farmers were interviewed using a structured questionnaire instrument. Of the 52 farmers 65 percent were subsistence, 27 percent back-yard and 8 percent emerging farmers. The primary data collected included demography, production practices, herd structure, feeds and feeding, breeding practices, marketing, and conservation methods. Two indigenous pig farmers and one exotic pig farmers were selected for purpose of measuring growth and other linear traits of piglets over a period of two months. Four hundred and nine (409) pigs were used for body measurements of which 124 were from emerging farms, 71 from subsistence and 206 from back-yard farms. Data was analysed using SAS Package (SAS, Version 9.3). Demographic representation of farmers showed 79 percent of farmers being males, 85 percent married. With 50 percent between the ages of 55-64; 60 percent owning the farms and 83 percent Northern Sotho speaking farms. The majority of farmers (39 percent) had secondary education with 81 percent trained in production and over eight years of farming experience. The objective of farmers raising pigs was mainly for selling at a frequency of 60 percent. Over 70 percent of the farmers had a good grasp of controlling internal and external parasites. However, over 80 percent of the farmers did not vaccinate or get advice from extension officers. When comparing the production systems, there was no variation in the number of young pigs produced. Only 13 percent of the emerging farmers and eight percent in back-yard had proper housing. Only 10 percent of the farmers had financial assistance. That led to only 10 percent of the farmers able to feed complete rations to their animals. Cross breeding has been practiced within communal areas by over 75 percent of the farmers. Over 15 percent bought boars from commercial farmers. This practice enabled them to sell their piglets to private buyers at 50-60 kg at an average price of R500 – R1000. Though the value of indigenous breeds was rated high by over 63 percent the size and price compelled them to cross-breed. An establishment of an indigenous breeding program is highly recommended. / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)

A tese analisa o segmento industrial de insumos para a criação de suínos, um locus importante de inovações que transformam os produtos e os processos, afetam o desempenho dos animais e a qualidade da carne e, concomitantemente, sofrem e desencadeiam e mudanças institucionais no mercado e organizacionais nas firmas ligadas à produção de carne suína. As características e as mudanças do padrão de inovação dos insumos para a criação de suínos dos grupos industriais de medicamentos veterinários, nutrição animal e genética suína são estudados, focalizando especificamente a dinâmica da(s) trajetória(s) tecnológica(s) das firmas de genética suína, suas relações institucionais e organizacionais com o sistema de mercado e com o sistema tecnológico de carne suína. Considerando que o tempo é fator importante nos processos, propõe-se um modelo para a avaliação conjunta das mudanças produtivas e qualitativas nos suínos e em sua carne, permitindo inclusive a prospecção ordenada de tendências. O modelo é construído a partir da lógica fuzzy. A melhor compreensão da dinâmica inovativa e a análise de tendências de ação das firmas insumidoras auxiliam a formulação de sugestões para as políticas industrial e de fomento à inovação, à pesquisa e ao desenvolvimento tecnológico. / The present doctoral dissertation analyses the industrial segment of inputs for swine breeding, an important locus of innovations that transform the products and the processes, affects the animal development and the pork quality and, at the same time, provoke and are affected by institutional changes in the market and in the firms` structure organization linked to the pork production. The characteristics and the changes in the innovation standards of the inputs for swine breeding in the industrial groups of veterinary medicines, animal nutrition and swine genetics are studied, focusing specifically on the swine genetics firms technological(s) trajectory(ies) dynamics, on its institutional and organizational relations with the pork market system and with the pork technological system. As the time factor has a great importance throughout the process, the present dissertation also has the aim of proposing a model to evaluate productive and qualitative changes simultaneiously in the swine and in the pork, allowing an ordered projection of tendencies. This model is built using fuzzy logic.A better understanding of the innovative dynamics and an analysis of the behaviour of tendencies on the part of the firms dealing with raising of swine up to the final meat process help to suggest industrial, innovation and research, and technological development policies.

Simulation modeling is an active part of animal nutrition. These complex programs rely on mathematical functions to predict the performance of an animal. The Gompertz equation is a simple, but accurate function that fits animal growth data well. In conjunction with allometry, the growth of a specific genotype can be predicted. Only three parameters are needed to sufficiently describe a genotype, viz. protein weight at maturity (Pm), the Gompertz growth rate parameter (B) and the lipid to protein ratio at maturity (LPRm), These descriptors are lacking for commercial pig genotypes in South Africa, and this hinders the use of models in simulating nutrient requirements. It is the aim of this thesis to estimate these parameters in six South African pig genotypes. Thirty pigs from each of six commercial genotypes were analysed using a serial slaughter method in which pigs were slaughtered at 4 and 14 days of age, and at 30, 40, 70, 80, 90 and 100kg live weight. The animals were choice fed and were housed in conventional housing facilities. Analyses for protein, lipid, water, and ash contents of the empty body at the respective weights were performed. The results indicated that there were no significant differences between the six genotypes in terms of mature weights or B of the various body chemical components, or between the B values estimated for all components across genotypes. The mean of the estimated values for Pm, B and LPRm were 38,8 ± 2.1 kg, 0.012 ± 0.004 day(-1), and 1.16 kg/kg respectively and can therefore be used to adequately describe all six genotypes. The assumption made that all body components have a similar B value is supported. To investigate the possible effects of the environment on growth, a comparative trial was performed on 20 pigs each from genotypes 4, 5 and 6 using chambers in which the temperature could be controlled to within 1 degree C of the setting. All other experimental methodologies were similar to those adopted in the first experiment. No significant differences were found between the two housing facilities, in terms of the genetic parameters, within the respective genotypes supporting the findings of the previous trial. It may therefore be possible to estimate B using the live weight and estimating Pm and lipid at maturity using allometry, instead of going to the expense of a full serial slaughter trial. The allometric coefficients relating lipid, water and ash to protein were 1.18, 0.88 and 0.97 respectively. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002.

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.