Behavioral and physiological performance of different gilt breeds during lactation

We evaluated the maternal behavior, physiology, and reproductive performance of both Damin (Min-pig × Large White) and Large White gilts to identify the advantages hybrid sows offer with regard to stress relieve and improvement of the welfare level of sows during late lactation. First-parity Damin gilts (n = 40) and firstparity Large White gilts (n = 40) were farrowed in individual pens. Video surveillance was used to monitor the occurrence of lateral recumbency and compare it to other postures, such as ventral recumbency, defecation, urination, tail posture, sham-chewing, and bar-biting behaviors. Monitoring was conducted from 07:00 to 09:00 h and from 13:00 to 15:00 h on days 3 and 6 of each week from the third to the fifth week postparturition. In addition, the concentrations of tumor necrosis factor-α, interleukin-6, and salivary α-amylase were assessed. During the fourth week postpartum, Damin gilts showed a higher frequency of postural changes from lateral recumbency to other postures and less ventral recumbency, sham-chewing, and bar-biting behavior compared with Large White gilts. However, no significant differences were found between Damin and Large White gilts with regard to urination, defecation, tail wagging, and "tail low" behaviors. The concentrations of serum interleukin-6, salivary α-amylase, and serum tumor necrosis factor-α were higher in Damin gilts than in Large White gilts during the fifth week postpartum. Damin gilts partly achieve lower stress levels during late lactation and better animal welfare than purebred Large White gilts.(AU)

Phenotypic correlation of characteristics in the gilt performance test with an average number of live-born piglets through all achieved births, during the reproductive exploitation / Ligação fenotípica de características no teste de desempenho de leitões com um número médio de leitões nascidos vivos durante todos os nascimentos realizados, durante a exploração reprodutiva

Reproductive efficacy of sows dictates the level of profitability of the production itself, and the moment of testing and selection of gilts for breeding (as the parents of a future generation), represents a very important moment. Given the fact that the selection of gilts for breeding is partly based on the weight-gain in the test, in this study we examined the influence of a daily weight-gain of gilts in the test of the manifestation of important reproductive characteristics - the size of the litter of the first and the other parities, as well as the percentage of sows that gave birth in relation to previous breeding process. Data of the 11637 tested gilts that completed the performance test have been used for the test. The studied characteristics were: the weight-gain at the end of the test, the number of live-born piglets, the number of stillborn piglets and the number of grown-weaned piglets in the first litter and the total number of live-born piglets, the total number of stillborn piglets and the total number of grown-weaned piglets. The results obtained in this study showed the effect of weight-gain in the reproductive efficacy test in the number of the live-born piglets in the first and from the 2nd to the 9th parity, as well as the percentage of the sows included in the next breeding process. By including all selected independent variables that showed the adequate statistical significance in correlation with the dependent variable, the determination coefficient rises to a value of 0.098 which represents 9.80% of the influence on the dependent variable, that can be explained by the independent variable, which leads to the conclusion that the binding strength between the variable "average live" and all the independent variables: "the number of litters", the MLD depth" and "the back-fat thickness", is very weak, which is not a rare case in multiple regression.(AU)

A eficácia reprodutiva das porcas dita o nível de rentabilidade da própria produção, e o momento do teste e seleção de leitoas para reprodução (como os pais de uma geração futura) representa um momento muito importante. Dado o fato de que a seleção de leitoas para criação é parcialmente baseada no ganho de peso no teste, neste estudo examinamos a influência de um ganho de peso diário de leitoas no teste da manifestação de importantes características reprodutivas - o tamanho da ninhada da primeira e das outras paridades, assim como a porcentagem de porcas que deram à luz em relação ao processo de criação anterior. Os dados das 11637 leitoas testadas que completaram o teste de desempenho foram utilizados para o teste. As características estudadas foram: o ganho de peso ao final do teste, o número de leitões nascidos vivos, o número de leitões natimortos e o número de leitões desmamados na primeira ninhada e o número total de leitões nascidos vivos , o número total de leitões natimortos e o número total de leitões desmamados. Os resultados obtidos neste estudo mostraram o efeito do ganho de peso no teste de eficácia reprodutiva no número de leitões nascidos vivos na primeira e da segunda à nona paridade, bem como a porcentagem de porcas incluídas na próximo processo de criação. Ao incluir todas as variáveis independentes selecionadas que mostraram a significância estatística adequada em correlação com a variável dependente, o coeficiente de determinação sobe para um valor de 0.098 que representa 9.80% da influência sobre a variável dependente, que pode ser explicada pela variável independente, que leva à conclusão de que a força de ligação entre a variável "média viva" e todas as variáveis independentes: "o número de ninhadas", a profundidade MLD "e" a espessura de gordura "é muito fraca, o que não é raro caso em regressão múltipla.(AU)

Phenotypic correlation of characteristics in the gilt performance test with an average number of live-born piglets through all achieved births, during the reproductive exploitation / Ligação fenotípica de características no teste de desempenho de leitões com um número médio de leitões nascidos vivos durante todos os nascimentos realizados, durante a exploração reprodutiva

Reproductive efficacy of sows dictates the level of profitability of the production itself, and the moment of testing and selection of gilts for breeding (as the parents of a future generation), represents a very important moment. Given the fact that the selection of gilts for breeding is partly based on the weight-gain in the test, in this study we examined the influence of a daily weight-gain of gilts in the test of the manifestation of important reproductive characteristics - the size of the litter of the first and the other parities, as well as the percentage of sows that gave birth in relation to previous breeding process. Data of the 11637 tested gilts that completed the performance test have been used for the test. The studied characteristics were: the weight-gain at the end of the test, the number of live-born piglets, the number of stillborn piglets and the number of grown-weaned piglets in the first litter and the total number of live-born piglets, the total number of stillborn piglets and the total number of grown-weaned piglets. The results obtained in this study showed the effect of weight-gain in the reproductive efficacy test in the number of the live-born piglets in the first and from the 2nd to the 9th parity, as well as the percentage of the sows included in the next breeding process. By including all selected independent variables that showed the adequate statistical significance in correlation with the dependent variable, the determination coefficient rises to a value of 0.098 which represents 9.80% of the influence on the dependent variable, that can be explained by the independent variable, which leads to the conclusion that the binding strength between the variable "average live" and all the independent variables: "the number of litters", the MLD depth" and "the back-fat thickness", is very weak, which is not a rare case in multiple regression.(AU)

A eficácia reprodutiva das porcas dita o nível de rentabilidade da própria produção, e o momento do teste e seleção de leitoas para reprodução (como os pais de uma geração futura) representa um momento muito importante. Dado o fato de que a seleção de leitoas para criação é parcialmente baseada no ganho de peso no teste, neste estudo examinamos a influência de um ganho de peso diário de leitoas no teste da manifestação de importantes características reprodutivas - o tamanho da ninhada da primeira e das outras paridades, assim como a porcentagem de porcas que deram à luz em relação ao processo de criação anterior. Os dados das 11637 leitoas testadas que completaram o teste de desempenho foram utilizados para o teste. As características estudadas foram: o ganho de peso ao final do teste, o número de leitões nascidos vivos, o número de leitões natimortos e o número de leitões desmamados na primeira ninhada e o número total de leitões nascidos vivos , o número total de leitões natimortos e o número total de leitões desmamados. Os resultados obtidos neste estudo mostraram o efeito do ganho de peso no teste de eficácia reprodutiva no número de leitões nascidos vivos na primeira e da segunda à nona paridade, bem como a porcentagem de porcas incluídas na próximo processo de criação. Ao incluir todas as variáveis independentes selecionadas que mostraram a significância estatística adequada em correlação com a variável dependente, o coeficiente de determinação sobe para um valor de 0.098 que representa 9.80% da influência sobre a variável dependente, que pode ser explicada pela variável independente, que leva à conclusão de que a força de ligação entre a variável "média viva" e todas as variáveis independentes: "o número de ninhadas", a profundidade MLD "e" a espessura de gordura "é muito fraca, o que não é raro caso em regressão múltipla.(AU)

Reproductive performance, retention rate, and age at the third parity according to growth rate and age at first mating in the gilts with a modern genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing. Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 0.05) on farrowing rate after first, second, and third mating. The total number of piglets born in the three first farrowing and over three parities were not affected (P > 0.05) by the age and GR at first mating. The retention rate until the third farrowing of gilts inseminated with more than 210 days of age was approximately 7% greater than in the gilts mated younger; however, no statistical difference (P > 0.05) was detected. An effect of the age at the first mating was observed in the age to reach the third farrowing. Gilts mated with less than 210 and more than 210 days reached the third farrowing, respectively, at 604.5 ±1.9 and 625.1 ± 2.7 days of age (P < 0.001). Discussion: With a minimum GR of 550 g/d, 180 days of age, and at least 130 kg of weight, gilts are eligible to be inseminated without impairing their litter size, farrowing, and retention rate until the third parity. [...]

Reproductive Performance, Retention Rate, and Age at the Third Parity According to Growth Rate and Age at First Mating in the Gilts with a Modern Genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing.Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 210 d and 210 d) and the growth rate (GR; 700 g/d and 700 g/d) at the first mating with a 2 × 2 factorial design. A real-time ultrasound examination was performed at approximately 28 days after artificial insemination to detect pregnancy. Afterward, the productivity data over three parities of 703 females were collected and analyzed at 28 co

Reproductive performance, retention rate, and age at the third parity according to growth rate and age at first mating in the gilts with a modern genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing. Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 0.05) on farrowing rate after first, second, and third mating. The total number of piglets born in the three first farrowing and over three parities were not affected (P > 0.05) by the age and GR at first mating. The retention rate until the third farrowing of gilts inseminated with more than 210 days of age was approximately 7% greater than in the gilts mated younger; however, no statistical difference (P > 0.05) was detected. An effect of the age at the first mating was observed in the age to reach the third farrowing. Gilts mated with less than 210 and more than 210 days reached the third farrowing, respectively, at 604.5 ±1.9 and 625.1 ± 2.7 days of age (P < 0.001). Discussion: With a minimum GR of 550 g/d, 180 days of age, and at least 130 kg of weight, gilts are eligible to be inseminated without impairing their litter size, farrowing, and retention rate until the third parity. [...](AU)

Avaliação da concentração plasmática de progesterona e eficiência do dispositivo intravaginal de liberação lenta de progesterona na sincronização do estro em marrãs

Resumo: A marrã é uma categoria animal de extrema importância dentro do sistema de produção de suínos, pois se trata das futuras matrizes do plantel. Um método eficaz para o preparo dessas futuras matrizes é a sincronização do estro através da utilização de hormônios o que reduzirá a mão de obra necessária para a detecção do estro e no número de marrãs de reposição, além de facilitar a inseminação artificial e, consequentemente, melhorará a sincronização e homogeneização dos grupos de parição. Apesar da sincronização do estro ser um assunto que vem sendo estudado há muitos anos, a quantidade de métodos disponíveis para tal é muito escassa. O presente estudo teve como objetivo avaliar a utilização de um dispositivo intravaginal de liberação lenta de progesterona desenvolvido para a espécie suína em relação à concentração plasmática de progesterona, sincronização do estro e os parâmetros reprodutivos em marrãs púberes. Neste experimento foram utilizadas 30 marrãs, divididas em 3 grupos, G1 (n=10) Grupo Controle, G2 (n=10) Altrenogest e G3 (n=10) Dispositivo intravaginal de liberação lenta de Progesterona. As marrãs dos grupo G2 e G3 receberam o tratamento por 18 dias consecutivos. Todas as fêmeas, independente do seu tratamento, foram inseminadas no momento 0 (reflexo de tolerância ao homem observado pela primeira vez na presença de um macho adulto) e a cada 24 horas até o fim do estro. No 21º dia após a inseminação artificial foi realizado o diagnóstico de gestação e aos 29 ± 1 dia de gestação as fêmeas foram abatidas. Os três grupos experimentais foram avaliados quanto à sincronização do estro, perfil plasmático de progesterona e parâmetros reprodutivos. O intervalo entre o final do tratamento início do estro não foi afetado pela utilização do tratamento hormonal, assim como o momento da ovulação. Porém, a taxa de prenhez foi negativamente influenciada pela utilização do dispositivo intravaginal de liberação lenta de progesterona, entretanto, a taxa de fertilidade não foi influenciada pelos tratamentos. Apesar do peso e tamanho do útero, concentração plasmática de progesterona e viabilidade não terem sido influenciados pelos tratamentos, a progesterona do dispositivo intravaginal de liberação lenta de progesterona influenciou no tamanho e peso das vesículas embrionárias, sendo estes maiores do que aos dos demais grupos, evidenciando a influência da progesterona nessa característica.

Abstract: Gilt is an extremely important animal category within the pig production system, since it is the future of the breeding herd. An effective method for the preparation of these future females is the estrus synchronization by the use of hormones, which will reduce the labor necessary for the detection of estrus and the number of gilts, as well as facilitate artificial insemination and, consequently, improve the synchronization and homogenization of the farrowing groups. Although synchronization of estrus is a subject that has been studied for many years, the number of available methods is very low. The objective of the present study was to evaluate the use of a slow release intravaginal progesterone device developed for swine in relation to plasma progesterone concentration, estrus synchronization and reproductive parameters in pubertal gilts. In this experiment 30 gilts were used and divided into 3 groups, G1 (n = 10) Control Group, G2 (n = 10) Altrenogest and G3 (n = 10) slow release intravaginal Progesterone device. G2 and G3 group gilts were treated for 18 consecutive days. All females, regardless of their treatment, were inseminated at time 0 (first tolerance reflex to the man observed in the presence of an adult boar) and every 24 hours until the end of estrus. On the 21st day after the artificial insemination, the diagnosis of gestation was performed and at 29 ± 1 day of gestation the females were slaughtered. The three experimental groups were evaluated for estrus synchronization, plasma progesterone profile and reproductive parameters. The interval between the end of treatment - estrus onset was not affected by the use of hormonal treatment, as well as the time of ovulation. However, the pregnancy rate was negatively influenced by the use of the slow release intravaginal progesterone device, however, the fertility rate was not influenced by the treatments. Despite the weight and size of the uterus, plasma concentration of progesterone and viability were not influenced by the treatments, these being larger than the other groups, evidencing the influence of progesterone on this characteristic.

AVALIAÇÃO DE DIFERENTES SISTEMAS DE ALOJAMENTO DURANTE A GESTAÇÃO DE LEITOAS NAS LESÕES, DESEMPENHO REPRODUTIVO E PESO DOS LEITÕES AO NASCER

O momento do agrupamento é um dos fatores de grande importância para o sucesso do alojamento coletivo para fêmeas suínas gestantes. O presente trabalho teve como objetivo comparar o agrupamento de leitoas em baias com sistema eletrônico de alimentação (ESF), agrupadas aos sete ou aos 30 dias após a cobertura, com o alojamento convencional em gaiolas. As fêmeas foram distribuídas aleatoriamente em três grupos, de acordo com o sistema de alojamento e momento após a cobertura: G= leitoas em gaiolas durante toda a gestação; B7= leitoas agrupadas em baias coletivas aos sete dias após a cobertura; B30= leitoas agrupadas em baias coletivas aos 30 dias após a cobertura. Foi observada maior taxa de parto (P<0,05) para o tratamento G comparado ao B7 (89,7 e 83,2, respectivamente). Não houve diferença entre os tratamentos na manutenção da gestação após 28 dias (P>0,05). Foi observada maior chance de ter maior escore de lesões corporais nos 3, 12 e 25 dias após o agrupamento nas fêmeas B7 e B30 em comparação a fêmeas G. Ao final da gestação, as fêmeas B7 e B30 também tiveram maior chance de lesões corporais, lesões de membros locomotores e claudicação em comparação às fêmeas G (P<0,05). Houve maior descarte por problemas locomotores no tratamento B7 do que nos tratamentos B30 e G (P<0,05). Não houve efeito do sistema ou momento de alojamento nas seguintes características da leitegada: total de leitões nascidos, nascidos vivos, mumificados, peso e variação do peso ao nascimento, número de leitões com peso <1000 g. Em conclusão, o alojamento de leitoas gestantes em baias coletivas com ESF, apesar de reduzir a taxa de parto quando agrupadas aos sete dias após a cobertura, pode ser efetuado aos 30 dias após a inseminação, sem prejuízo para o desempenho reprodutivo e características da leitegada, porém com maior escore de lesões durante a gestação quando comparados ao grupo alojado em gaiolas.

Time of mixing is a key factors that influencing the success of group housing system for gestating sows. The aim of this study was to evaluate the effects of time of mixing gilts in pens with electronic sow feeding (ESF) system, at d 7 or 30 after breeding, or housing in individual stalls. Gilts were randomly assigned to one of the three treatments: G= gilts housed in stalls throughout gestation; B7= gilts housed in pens 7 d after breeding; and B30= gilts housed in pens 30 d after breeding. Greater farrowing rate (P < 0.05) was observed for G than for B7 (89.7 and 83.2, respectively). There was no evidence for differences between treatments in maintaining the pregnancy after 28 d (P > 0.05). Greater chance of higher levels of body injury score was observed at 3, 12, and 25 d after mixing in B7 and B30 gilts compared to G gilts. At d 107 of gestation, B7 and B30 gilts were also more likely to have body injuries, locomotor injuries, and lameness compared with G gilts (P < 0.05). Cull rates of sows was higher due to locomotor problems in B7 than in B30 and G treatments (P < 0.05). There was no differences on the effect of housing system or time of mixing in total piglets born, born alive, mummified, piglet birth weight and coefficient of variation of birth weight within the litter, and proportion of piglets weighing <1000 g. In conclusion, despite B7 show lesser farrowing rate than G, mixing gestating gilts 30 d after breeding can be performed without impairing the reproductive performance and litter characteristics, however show higher injuries than gilts housing in individual stalls.

FATORES ENVOLVIDOS NO DESENVOLVIMENTO CORPORAL E DESEMPENHO REPRODUTIVO DE MATRIZES SUÍNAS

A alta variabilidade no peso ao nascer de leitões e o nascimento de leitões com pesos muito inferiores a média da leitegada evidencia a restrição de crescimento intrauterino, acentuada a partir da seleção genética de matrizes suínas mais prolíferas. Esses animais desenvolvem-se de maneira inferior aos seus contemporâneos e tem aumentado os riscos de morte ou descarte, acarretando menores índices produtivos. O objetivo deste estudo foi avaliar os efeitos do desenvolvimento intrauterino no crescimento, longevidade, produtividade e desempenho reprodutivo de futuras matrizes reprodutoras suínas. Além disso, avaliar a influência do desenvolvimento corporal e sua relação com puberdade e desempenho reprodutivo. No primeiro estudo, o peso ao nascer foi dividido em oito grupos e foram determinadas as curvas de crescimento e o desempenho reprodutivo até o terceiro parto de 1495 leitoas Landrace x Large White (DanBred®). Nas leitoas que pertenciam ao grupo mais leve, ou seja, com menos de 1 kg, o potencial de crescimento foi inferior do que as leitoas do grupo mais pesado, com menor ganho de peso diário (GPD) em todas as fases avaliadas (20, 70 e 170 dias) e com menor peso aos 170 dias, momento onde foi realizada a seleção para entrada no rebanho. A mortalidade e perdas cumulativas até os 170 dias foram maiores em leitoas pesando menos de 1 kg, reduzindo a oportunidade destas de serem selecionadas como futuras matrizes. Além disso, leitoas que nasceram com peso inferior a 1 kg tiveram menor número de dias de permanência no plantel e produziram quase 4,5 leitões a menos ao longo de três partos quando comparado com os outros grupos de peso ao nascer. O segundo estudo utilizou um total de 665 leitoas Landrace x Large White (DanBred®) para avaliar os efeitos da idade e taxa de crescimento no momento de exposição ao macho e suas consequências no desempenho reprodutivo. As leitoas foram retrospectivamente classificadas em grupos de acordo com idade a exposição ao macho (140-155 e 156170 dias) e taxa de crescimento até a exposição ao macho (Baixa: 500575 g/d; Intermediária: 580625 g/d; e Alta: 630790 g/d). Leitoas expostas ao macho com 140-155 dias tiveram menor manifestação de estro (60,8 vs. 77,0%) até os 30 dias do que àquelas expostas com 156-170 dias de idade. A manifestação de estro até 30 dias após a exposição ao macho foi maior para leitoas com alto ganho de peso (74,3%) do que as de ganho de peso baixo e intermediário (65,5 and 64,3%, respectivamente). A taxa de parto e o número de leitões nascidos no primeiro parto não foram afetados pela idade e pela taxa de crescimento. Os resultados dos nossos estudos apontam para a conclusão que o peso ao nascer e o desempenho de crescimento influenciam no desempenho reprodutivo das leitoas quando adultas.

The high variability on piglet birth weight and the birth of piglets weighing less than 1 kg show a restriction on intrauterine growth, increased by the large litter size of hyperprolific sows. These animals develop in lower rates than its contemporaries and have increased risk of death or culling, resulting in lower productivity. The aim of this study was to evaluate the effects of intrauterine development in growth, longevity, productivity and reproductive performance of sows destined to breeding herd. In addition, was to evaluate the influence of body development and its relation with puberty and reproductive performance. On the first study, using a retrospective classification into eight classes of birth weight were determined the growth and reproductive performance until the third parity of 1,495 crossbred Landrace x Large White gilts (DanBred®). Piglets from the lower birth weight group, i.e., less than 1 kg, had poorer growth performance when compared with the higher class, with lower body weight and average daily weight gain in all stages of development evaluated. Mortality and cumulative losses until 170 days of life were greater on piglets weighing less than 1 kg at birth, reducing the opportunity for their selection as future breeders. Furthermore, sows born weighing less than 1 kg had lower number of days in the breeding herd and produced almost 4.5 less piglets along three parities than the other gilts. A second study used a total of 665 Landrace x Large White gilts (DanBred®) to evaluate the effects of age and growth rate until the onset of boar exposure on first oestrus manifestation and reproductive performance. Gilts were retrospectively classified in groups according to their age at boar exposure (140-155 and 156170 days) and into classes according to their growth rate from birth to boar exposure (Low: 500575 g/d; Intermediate: 580625 g/d; and High: 630790 g/d). Gilts exposed to boar at 140-155 days had lower oestrus manifestation (60.8 vs. 77.0%) within 30 days than those exposed at 156-170 days of age. Lower percentages of gilts in oestrus within 30 days after boar exposure were observed in Low and Intermediate growth rate gilts (65.5 and 64.3%) than in High growth rate gilts (74.3%). Farrowing rate and number of total born litter size were affected neither by age or growth rate at onset of boar exposure. The results of our studies point to the conclusion that the birth weight and the developmental performance have influence on the reproductive performance of gilts as sows

Efeitos da ractopamina e de dois níveis de lisina digestível na dieta sobre o desempenho e características de carcaça de leitoas em terminação / Effects of ractopamine and two lysine levels on performance and carcass traits of gilts in the finishing phase

Avaliaram-se os efeitos da ractopamina e de dois níveis de lisina digestível na dieta sobre o desempenho e características de carcaça de leitoas com peso corporal a partir de 85kg, durante 21 e 28 dias antes do abate, os quais foram distribuídos em delineamento experimental de blocos ao acaso com cinco repetições de dois animais por unidade experimental. Os tratamentos consistiram de arranjo fatorial 2x2, com dois níveis de lisina digestível (LD), 0,67 e 0,87 por cento, e dois níveis de ractopamina (0 e 5ppm). Observou-se efeito significativo do nível de LD sobre o ganho de peso e peso corporal e interação significativa (P<0,05) entre o nível de LD e a ractopamina sobre a conversão alimentar e sobre a taxa de deposição de carne magra corporal. Não houve efeito significativo (P>0,05) do nível de LD sobre a espessura de toucinho, profundidade de lombo e rendimento em carne magra da carcaça de acordo com avaliação da carcaça, feita in vivo. Não houve efeito (P>0,05) da ractopamina sobre o consumo de ração, o ganho de peso diário e o peso corporal aos 21 e 28 dias de experimento. A ractopamina reduziu a espessura de toucinho no ponto P2 aos 21 dias e aumentou o rendimento de carne magra e a profundidade de lombo na avaliação da carcaça no frigorífico.(AU)

The effects of ractopamine and digestible lysine levels on performance and carcass traits of gilts with initial body weight average of 85kg, recorded during 21 and 28 day before slaughtering time were evaluated in a completely randomized block design with five replicates of two animals per experiment unit. The treatments consisted in a 2 x 2 factorial scheme, two levels of digestible lysine (DL) (0.67 and 0.87 percent) and two ractopamine levels (0 and 5ppm). Significant effects of DL on daily weight gain and body weight and significant effects of DL and ractopamine level were observed for feed:weight gain ratio and lean meat carcass deposition. No significant effects (P>0.05) of DL on fat thickness, muscle depth and lean meat yield according to the in vivo carcass evaluation were observed. No significant effect of ractopamine (P>0.05) on feed intake, daily weight gain and body weight (21 and 28 days) were observed. Ractopamine reduced back fat thickness at P2 point (21days) and increased lean meat yield and muscle depth in frigorific carcass evaluation.(AU)

Indução da puberdade e sincronização do cio subsequente em leitoas pré-púberes utilizando gonadotrofinas exógenas / Induction of puberty and following estrus synchronization in prepubertal gilts using exogenous gonadotropins

A utilização de gonadotrofinas exógenas na indução da puberdade e sincronização do estro e ovulação é uma prática que influencia positivamente no manejo das marrãs, para a mais efetiva e econômica inclusão no plantel de matrizes em Sistemas Intensivos de Produção de Suínos. No entanto, poucos estudos têm sido desenvolvidos com a finalidade de avaliar o grau de sincronização do estro seguinte à indução da puberdade. Assim sendo, o objetivo do presente estudo foi, justamente, o de verificar a taxa de sincronização do estro subseqüente à puberdade induzida hormonalmente, e a comparação das características dos estros, induzido e subseqüente a este. Sessenta e seis leitoas pré-púberes tiveram a puberdade induzida através de combinação hormonal utilizando gonadotrofinas (eCG e LH) aos 145 dias de idade em média. Das 66 fêmeas que iniciaram o experimento, 35 (53,03%) apresentaram cio até sete dias após a aplicação do LH, e 40 (60,60%) das 66 fêmeas tiveram o estro subseqüente sincronizado, ou seja, até o 25° dia após a aplicação do LH. Vinte e seis (39,39%) fêmeas manifestaram o primeiro e segundo cios. As 26 (39,39%) leitoas que não manifestaram o 2° cio de maneira sincronizada foram abatidas, sendo que 15 apresentaram corpos lúteos e/ou corpos albicans e 11 não apresentaram as estruturas mencionadas anteriormente, sendo consideradas imaturas. Não houve diferença significativa da duração do cio na puberdade com o cio subseqüente (P>0,05), tampouco da dispersão dos mesmos.(AU)

The utilization of exogenous gonadotropins in the puberty induction and estrus/ovulation synchronization is a management that influence positive1y gilts handle, to the better effectiveness and economic inclusion of gilts in the Intensive Swine Production System herd. However, few researches have been deve10ped to evaluate the subsequent estrus synchronization after puberty induction. Thus, the aim of this study was to verify the subsequent estrus synchronization after the hormonal puberty induction and to evaluate the inducted and the following one estrus characteristics. Sixty six prepubertal gilts had their puberty inducted by a hormonal combination using gonadotropins (eCG and LH) at 145 days old, in average. A total of 35 (52,03%) of the 66 initially gilts showed estrus up to seven days after LH administration, and 40 (60,60%) had the subsequent estrus synchronized (synchronization was defined as the gilts which showed estrus up to day 25 after LH administration). Twenty six gilts (39,39%) showed the first and second estrus. The 26 (39,39%) remaining gilts that didn't show the second estrus synchronized were slaughtered, which 15 presented corpus albicans and/or corpora lutea and 11 were considered immature because they didn't present any structure mentioned above in the ovaries. There was no significant difference between the puberty estrus duration and the subsequent estrus duration (P>0,05), neither their dispersion.(AU)

Desempenho produtivo de leitoas alimentadas com dietas de gestação de baixo ou alto nível de casca de soja

Gilts were fed gestation diets, with inclusion of 7% (T1) and 35% (T2) of soybean hulls which had fiber levels of 4.5 and 13.1%, respectively. After insemination, all females received 1.8kg of T1 diet (5470Kcal ME day-1) up to 35 days of gestation, when they were allocated to receive 2.4kg (7294Kcal ME day-1) of T1 (n= 108) or 2.7kg (7249Kcal ME day-1) of T2 (n= 99) diet. At 90 days of gestation T1 and T2 females started to receive 3.0kg (9117Kcal ME day-1) and 3.4kg (9129Kcal ME day-1) of T1 and T2 diets, respectively. The T1 females were heavier than T2 females, at 110 days of gestation and at parturition (P 0.05). However, the daily average feed intake during lactation was 5.3% higher for T2 (P=0.01) than for T1 females. There was no effect of treatments on milk production and composition, weight variation during lactation and weaning-to-estrus interval (P>0.05). Treatments were similar for total and born alive litter size, stillborn and mummified (P>0.05). The average birth weight was higher for T1 piglets (P=0.03), but litter weight was similar for treatments (P>0.05). Weaned litter size and weight did not differ for treatments (P>0.05). The two levels of soybean hulls in the gestation diets of gilts resulted in similar performance.

Leitoas foram alimentadas com dietas de gestação com inclusão de 7% (T1) e 35% (T2) de casca de soja, as quais continham níveis de 4,5 e 13,1% de fibra bruta, respectivamente. Após a inseminação, todas as fêmeas receberam 1,8kg da ração T1 (5470Kcal EM dia-1) até os 35 dias de gestação, quando foram separadas em dois grupos que receberam 2,4kg (7294Kcal EM dia-1) da ração T1 (n=108) ou 2,7kg (7249Kcal EM dia-1) da ração T2 (n=99). Aos 90 dias de gestação, as fêmeas T1 e T2 receberam respectivamente 3,0kg (9117Kcal EM dia-1) e 3,4kg (9129Kcal EM dia-1) de ração. As fêmeas T1 foram mais pesadas que as T2 aos 110 dias de gestação e ao parto (P 0,05). No entanto, o consumo diário médio de ração durante a lactação foi 5,3% maior para as fêmeas T2 (P=0,01) do que para as fêmeas T1. Não houve efeito dos tratamentos sobre a produção e composição do leite, a variação de peso das fêmeas durante a lactação e o intervalo desmame-estro (P>0,05). O número de nascidos totais, nascidos vivos, natimortos e mumificados foi semelhante (P>0,05) entre os tratamentos. O peso médio ao nascer foi maior (P=0,03) para os leitões das fêmeas T1, mas não houve diferença entre os tratamentos no peso médio da leitegada (P>0,05). O peso e número de leitões ao desmame não foram afetados pelos tratamentos (P>0,05). Os dois níveis de inclusão de casca de soja na dieta de gestação de leitoas resultaram em desempenho produtivo semelhante.

Desempenho produtivo de leitoas alimentadas com dietas de gestação de baixo ou alto nível de casca de soja

Gilts were fed gestation diets, with inclusion of 7% (T1) and 35% (T2) of soybean hulls which had fiber levels of 4.5 and 13.1%, respectively. After insemination, all females received 1.8kg of T1 diet (5470Kcal ME day-1) up to 35 days of gestation, when they were allocated to receive 2.4kg (7294Kcal ME day-1) of T1 (n= 108) or 2.7kg (7249Kcal ME day-1) of T2 (n= 99) diet. At 90 days of gestation T1 and T2 females started to receive 3.0kg (9117Kcal ME day-1) and 3.4kg (9129Kcal ME day-1) of T1 and T2 diets, respectively. The T1 females were heavier than T2 females, at 110 days of gestation and at parturition (P 0.05). However, the daily average feed intake during lactation was 5.3% higher for T2 (P=0.01) than for T1 females. There was no effect of treatments on milk production and composition, weight variation during lactation and weaning-to-estrus interval (P>0.05). Treatments were similar for total and born alive litter size, stillborn and mummified (P>0.05). The average birth weight was higher for T1 piglets (P=0.03), but litter weight was similar for treatments (P>0.05). Weaned litter size and weight did not differ for treatments (P>0.05). The two levels of soybean hulls in the gestation diets of gilts resulted in similar performance.

Leitoas foram alimentadas com dietas de gestação com inclusão de 7% (T1) e 35% (T2) de casca de soja, as quais continham níveis de 4,5 e 13,1% de fibra bruta, respectivamente. Após a inseminação, todas as fêmeas receberam 1,8kg da ração T1 (5470Kcal EM dia-1) até os 35 dias de gestação, quando foram separadas em dois grupos que receberam 2,4kg (7294Kcal EM dia-1) da ração T1 (n=108) ou 2,7kg (7249Kcal EM dia-1) da ração T2 (n=99). Aos 90 dias de gestação, as fêmeas T1 e T2 receberam respectivamente 3,0kg (9117Kcal EM dia-1) e 3,4kg (9129Kcal EM dia-1) de ração. As fêmeas T1 foram mais pesadas que as T2 aos 110 dias de gestação e ao parto (P 0,05). No entanto, o consumo diário médio de ração durante a lactação foi 5,3% maior para as fêmeas T2 (P=0,01) do que para as fêmeas T1. Não houve efeito dos tratamentos sobre a produção e composição do leite, a variação de peso das fêmeas durante a lactação e o intervalo desmame-estro (P>0,05). O número de nascidos totais, nascidos vivos, natimortos e mumificados foi semelhante (P>0,05) entre os tratamentos. O peso médio ao nascer foi maior (P=0,03) para os leitões das fêmeas T1, mas não houve diferença entre os tratamentos no peso médio da leitegada (P>0,05). O peso e número de leitões ao desmame não foram afetados pelos tratamentos (P>0,05). Os dois níveis de inclusão de casca de soja na dieta de gestação de leitoas resultaram em desempenho produtivo semelhante.

Reproductive Performance, Retention Rate, and Age at the Third Parity According to Growth Rate and Age at First Mating in the Gilts with a Modern Genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing.Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 210 d and 210 d) and the growth rate (GR; 700 g/d and 700 g/d) at the first mating with a 2 × 2 factorial design. A real-time ultrasound examination was performed at approximately 28 days after artificial insemination to detect pregnancy. Afterward, the productivity data over three parities of 703 females were collected and analyzed at 28 co

Reproductive Performance, Retention Rate, and Age at the Third Parity According to Growth Rate and Age at First Mating in the Gilts with a Modern Genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing.Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 210 d and 210 d) and the growth rate (GR; 700 g/d and 700 g/d) at the first mating with a 2 × 2 factorial design. A real-time ultrasound examination was performed at approximately 28 days after artificial insemination to detect pregnancy. Afterward, the productivity data over three parities of 703 females were collected and analyzed at 28 co

Reproductive Performance, Retention Rate, and Age at the Third Parity According to Growth Rate and Age at First Mating in the Gilts with a Modern Genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing.Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 210 d and 210 d) and the growth rate (GR; 700 g/d and 700 g/d) at the first mating with a 2 × 2 factorial design. A real-time ultrasound examination was performed at approximately 28 days after artificial insemination to detect pregnancy. Afterward, the productivity data over three parities of 703 females were collected and analyzed at 28 co

Reproductive Performance, Retention Rate, and Age at the Third Parity According to Growth Rate and Age at First Mating in the Gilts with a Modern Genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing.Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 210 d and 210 d) and the growth rate (GR; 700 g/d and 700 g/d) at the first mating with a 2 × 2 factorial design. A real-time ultrasound examination was performed at approximately 28 days after artificial insemination to detect pregnancy. Afterward, the productivity data over three parities of 703 females were collected and analyzed at 28 co

Reproductive Performance, Retention Rate, and Age at the Third Parity According to Growth Rate and Age at First Mating in the Gilts with a Modern Genotype

Background: Gilts represent the largest category (18-20%) of female pigs in a breeding herd. Under field conditions, the amplitude of growth rate and age at the first mating of gilts are remarkably higher than the recommendations made by the genetic companies. There are several studies that have considered the management of these animals starting from their introduction to the herd till the mating. It has been noted that the genetic selection constantly promotes evolution that may change certain traits of these animals. However, there is a lack of the studies that evaluate the management strategies suitable for the modern sows. This study, therefore, aimed to evaluate the effect of age and growth rate of gilts at the first mating on productive performance and retention rate until the third farrowing.Materials, Methods & Results: The study was performed in a gilt development unit (GDU) with a breeding stock capacity of 1000 females and a goal of 90 gilts mating per week. The groups were retrospectively created according to age ( 210 d and 210 d) and the growth rate (GR; 700 g/d and 700 g/d) at the first mating with a 2 × 2 factorial design. A real-time ultrasound examination was performed at approximately 28 days after artificial insemination to detect pregnancy. Afterward, the productivity data over three parities of 703 females were collected and analyzed at 28 co

Serum concentrations of creatine kinase and of triglycerides during lactation in gilts bred older and in multiparous sows fed ad libitum

The aim of this paper was to assess the possible variation in blood concentrations of creatine kinase (CK) and triglycerides in gilts bred older in comparison with multiparous sows. Ten primiparous and ten Camborough multiparous sows from the fourth to seventh parities were used. Breeding age and weight of gilts averaged respectively 231 days and 149.5kg. All females were moved into individual farrowing crates and were managed under the same conditions. Blood samples were collected by puncturing the coccygeal artery on day 7 before expected farrowing, and on days 2, 7, 14, 21 of lactation and 2 days after weaning. No difference in triglycerides and CK serum concentrations between groups were observed. The CK levels were low before farrowing, increased substantially on days 2 and 7 and decreased toward the end of lactation. The concentrations of triglycerides were slightly high before the parturition, diminished on days 2, 7, 14 and 21 and increased after weaning.

O objetivo deste trabalho foi verificar as possíveis variações na concentração sangüínea de CK e de triglicérides em porcas primíparas cobertas tardiamente, em comparação com porcas multíparas. Foram utilizadas dez porcas primíparas e dez multíparas, com ordem de parição entre 5 e 7 anos, todas da linhagem Camborough. A cobrição efetiva das leitoas ocorreu na idade média de 231 dias, com 149,5kg. Todas as fêmeas foram alojadas em gaiolas individuais de parição e mantidas sob as mesmas condições. As amostras de sangue foram colhidas por punção da artéria coccígea 7 dias antes do parto previsto, nos dias 2, 7, 14 e 21 de lactação e 2 dias após o desmame. Não foi observada diferença significativa na concentração sérica de CK e de triglicérides entre os dois grupos. A concentração de CK foi baixa antes do parto, elevou-se substancialmente nos dias 2 e 7 de lactação e decresceu progressivamente até o final da lactação. A concentração de triglicérides foi ligeiramente maior antes do parto, diminuindo nos dias 2, 7, 14 e 21 da lactação, voltando a elevar-se após a desmama.