Master of Science / Department of Animal Sciences and Industry / Robert D. Goodband / A study was conducted on a commercial sow farm to determine the effects of parity and stage of gestation on growth and feed efficiency of gestating sows. These data were also used to model changes in composition of maternal weight gain and products of conceptus throughout gestation. Feed intake and BW were measured daily from d 5 to 112 of gestation for 712 females. From d 5 to 39 of gestation, ADFI was lowest for parity 3+ sows compared to the other periods of gestation. Parity 2 sows, although provided the same feed allowance, had greater ADFI during the first period than parity 3+ sows. Average daily gain was lowest and G:F was the poorest from d 5 to 39 for each parity group compared with d 40 to 109 of gestation. Parity 1 and 2 sow ADG increased following d 39 of gestation but decreased from d 75 to 109. Parity 3+ sow ADG increased in each subsequent period of gestation. Parity 1 sows had the greatest ADG and G:F in comparison to parity 2 and 3+ sows in each period of gestation. Energy available for maternal growth was estimated after accounting for the energy needed to meet the sow’s maintenance requirement and the energy required for the growth of the conceptus. Following d 39 of gestation, energy available for maternal growth decreased at the expense of maintenance and conceptus requirements in each subsequent period of gestation for each parity group. After accounting for the weight of the conceptus, maternal ADG decreased from d 39 to 74, and increased d 74 to 109 of gestation, regardless of parity. Maternal G:F was greatest for parity 1 sows in most gestation periods. In conclusion, parity and stage of gestation impact sow feed efficiency and maternal growth with parity 1 sows having the greatest weight gain and best feed efficiency.

The shift to group-housing of the breeding herd makes it difficult to manage animals individually. To maximize sow longevity and reproductive performance, gilts must be bred on second heat weighing between 135 and 160 kg. As gilts are typically fed ad libitum (AD), they often exceed targeted breeding weights, leading to structural and other problems resulting in culling at early parities. Thus, utilization of an electronic sow feeder (ESF) enables caretakers to manage animals individually in group-housing situations, by allotting predetermined amounts of feed. The specific objectives of this study were to: 1) to determine the effects of AD or restricted (RS) feeding bases (FB) on growth and sexual development in replacement gilts using an ESF; 2) to determine the growth and reproductive responses to gonadotropins in gilts fed on either AD or RS feeding bases using an ESF; and 3) to ascertain the effects of short-term increases in feed allowances on growth and sexual development in previously feed-restricted gilts using an ESF. Gilts employed in all studies were acclimated to an ESF (ACCUTEAM, Osborne Industries, Osborne, KS) beginning at 150 d of age, during a 10-d training period. Across all experiments, treatments were assigned at 160 d of age. In experiments 1 and 2, gilts received feed on either AD (5.00 kg/d) or RS (2.72 kg/d) bases. In the first study, estrus detection began at 160 d of age. In experiment 2, gilts assigned to receive gonadotropins were treated at 170 d of age, with estrus detection beginning the next d. Gilts fed on the RS basis were observed to have improved feed conversion efficiency compared to AD-fed gilts in experiments 1 and 2 (both P < 0.01); and flushed gilts in experiment 3 had G: F similar to RS gilts. Average daily gain was not affected by FB in the first and third experiments, however AD-fed gilts gained weight at a faster rate (P = 0.02) than RS gilts in experiment 2. Gilts fed AD consumed their allotments across more meals than those fed RS. Age at puberty onset was not affected by FB in any of the experiments. Further, P.G. 600 did not hasten the onset of puberty, irrespective of FB in experiment 2. In experiment 3, ovulation rate was numerically greatest for flushed gilts, and was significantly greater than RS gilts (P = 0.05). The ovulation rate for flushed gilts was similar to AD gilts. Across all experiments, feed disappearance was observed to decrease as AD-fed gilts approached estrus. In this series of experiments, FB did not alter puberty onset, however ovulation rate was increased when gilts were allocated short-term increases in feed allowances. Further, utilizing an ESF may augment current industry estrus detection methods by monitoring feeding behavior. / Doctor of Philosophy / On commercial swine operations in the U.S. sow removal rates due to death and culling exceed 40% annually. On average, sows are culled at parity 3 or 4, while at least this many parities are required before investment costs are recouped. Gilts are typically fed AD until BW of 135 kg are attained by approximately 200 d of age. Oftentimes, gilts fed on AD basis exceed targeted breeding weights, leading to structural and other problems resulting in culling at early parities. To improve sustainability and competitiveness of pork production systems, the industry must focus on proper gilt management practices to facilitate successful entry into the breeding herd and increase longevity and lifetime performance as sows. A series of 3 experiments were conducted to evaluate different feeding bases on growth and sexual development in gilts. The first experiment evaluated the impact of AD or RS feeding on growth and sexual development in gilts using an ESF. Age at puberty was not different in limit-fed gilts. Limit-fed gilts also grew at a similar rate accompanied with improved feed conversion compared to AD fed gilts. Results from this experiment indicate that gilts can be limit-fed prior during the period around puberty until entering the breeding herd without negative impacts to growth or sexual development. In the second experiment, the same feeding bases were utilized, but within feeding basis groups, gilts either received or did not receive treatment with exogenous gonadotropins. Age at puberty was similar, regardless of feeding basis or gonadotropin treatment. Feed conversion was improved in limit-fed gilts, however daily gain was improved for gilts receiving feed AD. Results from this experiment imply that limit feeding gilts has no negative impacts on sexual development, but daily gain is reduced. In the third experiment, previous feeding bases were used, and a third, nutritional flushing, was also studied, when gilts received AD feed 7 d after first estrus. Flushed gilts had feed conversion like that of limit-fed gilts with daily gain similar to that of AD gilts. Gilts which were flushed had ovulation rates which were similar to gilts receiving feed AD but was greater compared with limit-fed gilts. Results indicate that flush feeding can achieve daily gain similar to ad libitum feeding and feed conversion similar to limit-feeding, while improving ovulation rate compared to limit-feeding. Across all studies, feed disappearance decreased for AD fed gilts as they neared estrus. Overall, using an ESF allows for precise feeding of replacement gilts and allows producers to implement various feeding strategies across multiple animals on an individual basis. Monitoring feed behavior with an ESF may enhance current estrus detection practices.

A exigência de consumidores por alimentos originados de sistemas que forneçam boas condições de vida aos animais de produção consiste numa realidade em inevitável crescimento. Legislações internacionais elaboradas por demanda de mercado pressionam os produtores e a indústria brasileira a cumprir normas que estabelecem padrões mínimos de bem-estar animal (BEA). No caso específico da suinocultura, um dos aspectos mais polêmicos é o alojamento das matrizes durante a gestação. As gaiolas individuais, sistema convencional no Brasil, promove limitação física e social, além de predispor a distúrbios locomotores e comportamentais. Por outro lado, o sistema proposto para melhorar o BEA, as baias coletivas, provocam outros problemas, como as brigas por disputa hierárquica e por alimento, e o baixo controle individual, que poderiam prejudicar o desempenho reprodutivo. Dessa forma, um equipamento individual de arraçoamento automatizado (ESF) foi desenvolvido para amenizar essa situação. Para descobrir o efeito do alojamento em grupo com o ESF no desempenho reprodutivo das matrizes, foi realizada uma comparação de dados reprodutivos dos dois sistemas, localizados numa mesma propriedade. Dados mensais de três anos foram coletados dos registros das granjas e analisados por teste T-Student para as variáveis paramétricas e por teste de Mann-Whitney para as não paramétricas. De acordo com os resultados, o desempenho das matrizes alojadas em baias foi superior. Apenas a média do peso do leitão ao nascimento foi significantemente inferior em relação ao sistema individual, sugerindo que a conversão de sistemas é não apenas favorável ao BEA e ao mercado exigente, mas também para a produtividade. Além da questão do produtor, é essencial avaliar a percepção do consumidor brasileiro quanto ao BEA, visto que seu poder de compra é uma forte influência no mercado, e que apenas as exigências internacionais não são suficientes para provocar mudanças em todos os sistemas de produção do país. Por isso, também foi realizado um levantamento com consumidores. Utilizou-se dois métodos de coleta: online e em campo (pontos de comércio), para uma maior abrangência e representatividade. Os dados coletados foram analisados por estatística descritiva, e o teste Qui-quadrado foi aplicado para avaliar se houve associação entre a distribuição das respostas e o perfil dos participantes. Ambas as pesquisas demonstraram que o consumidor reconhece a senciência dos animais de produção, sente que é dada pouca importância ao tema no Brasil, enquanto consideram o governo como principal responsável por promover melhorias. Concordam que consumir produtos com certificação em BEA pode contribuir para melhorar as condições dos animais, apesar de não conseguirem identificar o selo nas embalagens. Além disso, apesar dos participantes alegarem não conhecer os sistemas de produção atuais, demonstraram interesse sobre o assunto e disposição para pagar mais por produtos certificados. No entanto, algumas respostas devem ser indagadas quando pareadas com o real comportamento do consumidor. / Consumer\'s demand for animal-friendly food is an inevitably growing reality. International legislation drawn up by market demand pressure Brazilian farmers and the industry to comply with minimum animal welfare standards. Specifically in pig production, one of the most controversial aspects is the housing of sows during gestation. Individual crates, which is the conventional system in Brazil, promote physical and social restriction, and predispose to lameness and behavioural disorders. On the other hand, group pens were proposed system to improve animal welfare, but bring other problems, such as hierarchical and food competition aggression, and low individual control, which could impair reproductive performance. In this way, electronic sow feeder (ESF) was developed to mitigate this situation. So, to find out the effect of group housing with ESF system on reproductive performance of sows, a comparison of reproductive data of both systems, located in the same farm, was performed. Monthly data of three years were collected from the farm records and analyzed by T-Student Test for parametric variables and Mann-Whitney Test for the non-parametric variables. According to the results, group housing showed better performance. Only piglet weight at birth was significantly higher in individual housing, suggesting that the conversion of housing systems is not only favourable to farm animal welfare (FAW) and to demanding market, but also to productivity. In addition to the farmer issue, it is essential to evaluate Brazilian consumer\'s perception of FAW, since his/her purchasing power causes strong impact on market. Besides, international legislation is not enough to bring about changes in all Brazilian farms and food industries. Therefore, a consumer survey was conducted. Two data collection methods were used: online and in loco (marketplaces). for greater number of answers and representativeness. Collected data were analyzed by descriptive statistics, and chi-square Test was applied to evaluate if there was association between answers\' distribution and participants\' profile. Both surveys have shown that consumer recognizes farm animals\' sentience, feels that little importance is given to the subject in Brazil, while he/she considers the government as the main responsible for promoting FAW. They agree that consuming animal-friendly products can help improve animals\' conditions, even though they cannot identify certification seal. In addition, while participants claim they are not familiar to farming systems, they have shown interest in the topic and willingness to pay more for certified products. However, some answers should be analyzed when paired with actual consumer behaviour.

A exigência de consumidores por alimentos originados de sistemas que forneçam boas condições de vida aos animais de produção consiste numa realidade em inevitável crescimento. Legislações internacionais elaboradas por demanda de mercado pressionam os produtores e a indústria brasileira a cumprir normas que estabelecem padrões mínimos de bem-estar animal (BEA). No caso específico da suinocultura, um dos aspectos mais polêmicos é o alojamento das matrizes durante a gestação. As gaiolas individuais, sistema convencional no Brasil, promove limitação física e social, além de predispor a distúrbios locomotores e comportamentais. Por outro lado, o sistema proposto para melhorar o BEA, as baias coletivas, provocam outros problemas, como as brigas por disputa hierárquica e por alimento, e o baixo controle individual, que poderiam prejudicar o desempenho reprodutivo. Dessa forma, um equipamento individual de arraçoamento automatizado (ESF) foi desenvolvido para amenizar essa situação. Para descobrir o efeito do alojamento em grupo com o ESF no desempenho reprodutivo das matrizes, foi realizada uma comparação de dados reprodutivos dos dois sistemas, localizados numa mesma propriedade. Dados mensais de três anos foram coletados dos registros das granjas e analisados por teste T-Student para as variáveis paramétricas e por teste de Mann-Whitney para as não paramétricas. De acordo com os resultados, o desempenho das matrizes alojadas em baias foi superior. Apenas a média do peso do leitão ao nascimento foi significantemente inferior em relação ao sistema individual, sugerindo que a conversão de sistemas é não apenas favorável ao BEA e ao mercado exigente, mas também para a produtividade. Além da questão do produtor, é essencial avaliar a percepção do consumidor brasileiro quanto ao BEA, visto que seu poder de compra é uma forte influência no mercado, e que apenas as exigências internacionais não são suficientes para provocar mudanças em todos os sistemas de produção do país. Por isso, também foi realizado um levantamento com consumidores. Utilizou-se dois métodos de coleta: online e em campo (pontos de comércio), para uma maior abrangência e representatividade. Os dados coletados foram analisados por estatística descritiva, e o teste Qui-quadrado foi aplicado para avaliar se houve associação entre a distribuição das respostas e o perfil dos participantes. Ambas as pesquisas demonstraram que o consumidor reconhece a senciência dos animais de produção, sente que é dada pouca importância ao tema no Brasil, enquanto consideram o governo como principal responsável por promover melhorias. Concordam que consumir produtos com certificação em BEA pode contribuir para melhorar as condições dos animais, apesar de não conseguirem identificar o selo nas embalagens. Além disso, apesar dos participantes alegarem não conhecer os sistemas de produção atuais, demonstraram interesse sobre o assunto e disposição para pagar mais por produtos certificados. No entanto, algumas respostas devem ser indagadas quando pareadas com o real comportamento do consumidor. / Consumer\'s demand for animal-friendly food is an inevitably growing reality. International legislation drawn up by market demand pressure Brazilian farmers and the industry to comply with minimum animal welfare standards. Specifically in pig production, one of the most controversial aspects is the housing of sows during gestation. Individual crates, which is the conventional system in Brazil, promote physical and social restriction, and predispose to lameness and behavioural disorders. On the other hand, group pens were proposed system to improve animal welfare, but bring other problems, such as hierarchical and food competition aggression, and low individual control, which could impair reproductive performance. In this way, electronic sow feeder (ESF) was developed to mitigate this situation. So, to find out the effect of group housing with ESF system on reproductive performance of sows, a comparison of reproductive data of both systems, located in the same farm, was performed. Monthly data of three years were collected from the farm records and analyzed by T-Student Test for parametric variables and Mann-Whitney Test for the non-parametric variables. According to the results, group housing showed better performance. Only piglet weight at birth was significantly higher in individual housing, suggesting that the conversion of housing systems is not only favourable to farm animal welfare (FAW) and to demanding market, but also to productivity. In addition to the farmer issue, it is essential to evaluate Brazilian consumer\'s perception of FAW, since his/her purchasing power causes strong impact on market. Besides, international legislation is not enough to bring about changes in all Brazilian farms and food industries. Therefore, a consumer survey was conducted. Two data collection methods were used: online and in loco (marketplaces). for greater number of answers and representativeness. Collected data were analyzed by descriptive statistics, and chi-square Test was applied to evaluate if there was association between answers\' distribution and participants\' profile. Both surveys have shown that consumer recognizes farm animals\' sentience, feels that little importance is given to the subject in Brazil, while he/she considers the government as the main responsible for promoting FAW. They agree that consuming animal-friendly products can help improve animals\' conditions, even though they cannot identify certification seal. In addition, while participants claim they are not familiar to farming systems, they have shown interest in the topic and willingness to pay more for certified products. However, some answers should be analyzed when paired with actual consumer behaviour.