Performance and behavior of piglets fed diets with different metabolizable energy levels / Desempenho e comportamento de leitões alimentados com dietas com diferentes níveis de energia metabolizável

This study evaluated the effect of different metabolizable energy (ME) levels in diets on digestibility, performance, and feeding behavior of weaned piglets. A digestibility study to determine ME levels was performed using 12 male piglets with 11.5 ± 0.5 kg body weight (BW), in a cross-over design fed with different ME levels (treatments). In the performance study were used 64 female piglets with 7.5 ± 0.8 kg BW, in a randomized block design with four treatments (3.30, 3.40, 3.50, and 3.60 Mcal.kg-1 ME levels), and feeding program with three phases (pre-initial I, pre-initial II, and initial). For feeding behavior, four pens of each treatment were monitored with cameras. The crude-protein digestibility coefficient reduced as dietary ME level increased (P <0.05). In pre-initial I animal performance was not influenced (P <0.05) by ME diet levels, and in the pre-initial II and initial phases, increases in ME caused quadratic (r² 0.99) and linear (r² 0.99) effects on daily feed intake, respectively. When ME levels increased, feed conversion ratio decreased linearly in the pre-initial II phase (r² =0.98), and quadratically in the initial phase (r²= 0.99). The number and duration of feeder visits linearly decreased as the diet energy levels increased (P <0.05). Weaned piglets can regulate feed intake according to dietary ME levels. The performance of weaned piglets can be maintained using diets containing metabolizable energy levels between 3.30 at 3.60 Mcal.ME.kg-1 if the ratio of nutrients to energy is maintained constant.The feed intake behavior of weaned piglets is influenced by increases in dietary metabolizable energy levels evaluated, resulting in fewer and shorter visits to the feeder.

Este estudo avaliou o efeito de diferentes níveis de energia metabolizável (EM) em dietas sobre a digestibilidade, desempenho e comportamento alimentar de leitões desmamados. Um estudo de digestibilidade para determinação dos níveis de EM foi realizado com 12 leitões machos com 11,5 ± 0,5 kg de peso corporal, em delineamento cruzado, alimentados com diferentes níveis de EM (tratamentos). No estudo de desempenho foram utilizadas 64 leitões fêmeas com peso corporal de 7,5 ± 0,8 kg, em delineamento de blocos casualizados com quatro tratamentos (níveis de 3,30, 3,40, 3,50 e 3,60 Mcal.kg-1 ME), e programa de alimentação com três fases (pré- inicial I, pré-inicial II e inicial). Para o comportamento alimentar, quatro baias de cada tratamento foram monitorados com câmeras. O coeficiente de digestibilidade da proteína bruta diminuiu com o aumento do nível de EM da dieta (P <0,05). No pré-inicial I o desempenho dos animais não foi influenciado (P <0,05) pelos níveis da dieta de EM, e nas fases pré-inicial II e inicial, o aumento de EM causou efeitos quadráticos (r² 0,99) e lineares (r² 0,99) na alimentação diária ingestão, respectivamente. Quando os níveis de EM aumentaram, a conversão alimentar diminuiu linearmente na fase pré-inicial II (r² = 0,98), e quadraticamente na fase inicial (r² = 0,99). O número e a duração das visitas aos comedouros diminuíram linearmente à medida que os níveis de energia da dieta aumentaram (P <0,05). Leitões desmamados podem regular o consumo de ração de acordo com os níveis de EM da dieta, o desempenho de leitões desmamados pode ser mantido usando dietas contendo níveis de energia metabolizável entre 3.30 a 3.60 Mcal.EM.kg-1 se a proporção de nutrientes para energia for mantida constante. O comportamento de consumo de ração de leitões desmamados é influenciado pelo aumento nos níveis de energia metabolizável da dieta avaliados, resultando em menos e mais curtas visitas ao comedouro.

Immunocastrated female pigs' social and feeding behaviour

- This study compared the social and feeding behaviour of immunocastrated female pigs using different immunocastration protocols. We used seventy-two gilts from industrial crossbreeding (Agroceres × Topigs) at 15 weeks of age. The pigs were distributed in a randomised design with three treatments. The second dose of the immunocastration vaccine was applied in two groups, six weeks before slaughter (I6) and four weeks before slaughter (I4). A non-immunised group (NI) was used for comparison. Due to the divergence in the time of immunisation between the two groups, an individual comparison of each immunocastrated group with the control group (NI vs. I6 and NI vs. I4) was performed. Social behaviour was analysed through the collection of images by a monitoring camera, and the analysis period was from 6:00 to 18:00 h, with behaviour observed every ten minutes. Feeding behaviour data were collected by the automated FIRE® system. Anti-GnRH immunisation and the different protocols of application did not influence most social and feeding behaviours.(AU)

Evaluation of piglet birth weight on growth performance and qualitative and quantitative characteristics of carcasses of immunocastrated pigs

The objective of this study was to determine the effect of birth weight on growth performance, carcass characteristics, and meat quality of immunocastrated male pigs. Seventy-two boars were assigned to three birth weight categories (BiW): light BiW pigs (LP: 0.98±0.083 kg BW; n = 24), normal BiW pigs (NP: 1.42±0.067 kg BW; n = 24), and heavy BiW pigs (HP: 1.85±0.096 kg BW; n = 24). For treatment design, we considered a weight range of two standard deviations (SD) in relation to the average population body weight (from 0.785 to 2.155 kg BW−1 ). The animals were housed in six pens with 12 animals per pen, with ad libitum access to water and feed throughout the study. In the growing and finishing phases, pigs were immunocastrated with two doses of vaccine at 112 and 161 days of age. The three BiW categories were different up to departure from the nursery (70 days). After this period, there was no difference between NP and HP in terms of BiW. Measurements showed that a low BiW reduced the loin eye area (9.4%), longissimus thoracis muscle depth (7.6%), and meat:fat ratio (21.6%). Backfat thickness (21.5%) and fat area (11.8%) were higher in LP as compared with the NP and HP categories. Light BiW pigs presented a lower weight steak (7.0%) and belly + rib (8.6%) compared with NP and HP, but did not differ within the LP group. Light BiW pigs required a greater lodging time (14 days), generating higher accumulated feed intake to reach the same slaughter BiW as the other categories. Growth performance and carcass characteristics are influenced by the birth weight (BiW) category. Light BiW pigs require more time and feed intake to reach the same slaughter weight. Birth weight has positive effects on meat quality and weight of commercial cuts.

Digestibility and net energy prediction of rice by products determined with piglets / Digestibilidade e predição da energia líquida de subprodutos de arroz determinado com leitões

The aim of this study was to determine the chemical composition, digestibility, and net energy (NE) of broken rice (BRR), stabilized rice bran (SRB), and parboiled rice bran (PRB) for piglets. Two digestibility trials were performed with 12 and 18 male pigs with initial weights of 8 and 16kg, respectively. We performed total fecal collection using ferric oxide as fecal marker. The digestibility coefficients of organic matter, crude protein, and gross energy were higher (P<0.001) for the BRR compared to the SRB and PRB. The PRB presented a digestible energy 2% lower than that of BR and 5% higher than that of SRB. For BRR, average NE value was 3,228kcal/kg dry matter (DM), and the difference between the lower and higher value was 311kcal/kg DM. Average NE values of SRB and PRB were 2,896 and 3,293kcal/kgDM, respectively. The difference between the energy predicted by each equation reached 190kcal/kgDM for SRB and 285kcal/kgDM for PRB. In conclusion, BRR showed higher nutrient digestibility coefficients, except for EE and GE, which can be attributed to differences in the production processes. Regardless of the type of feedstuff tested, equations to predict NE values should be used carefully due to considerable differences in energy content.

O objetivo deste estudo foi determinar a composição química, a digestibilidade e a energia líquida (EL) da quirera (QR), farelo de arroz estabilizado (FAE) e farelo de arroz parboilizado (FAP) para leitões. Foram realizados dois ensaios de digestibilidade com 12 e 18 suínos machos com pesos iniciais de 8 e 16kg, respectivamente. A coleta fecal total foi realizada usando óxido férrico como marcador fecal. Os coeficientes de digestibilidade da matéria orgânica, proteína e energia bruta (EB) foram maiores (P<0,001) para o QR em comparação com o FAE e FAP. O FAP apresentou energia digestível 2% inferior à da QR e 5% maior que a da FAE. Para QR, o valor médio de EL foi de 3,228kcal/kg de matéria seca (DM), e a diferença entre o valor inferior e o valor superior foi de 311kcal/kg de MS. Os valores médios de EL de FAE e FAP foram de 2.896 e 3.293kcal/kgMS, respectivamente. A diferença entre a energia predita por cada equação atingiu 190kcal/kgMS para FAE e 285kcal/kgMS para FAP. Em conclusão, QR mostrou maiores coeficientes de digestibilidade dos nutrientes, exceto EE e EB, o que pode ser atribuído a diferenças nos processos de produção. Independentemente do tipo de alimento testado, as equações para prever os valores de EL devem ser usadas com cuidado devido a diferenças consideráveis no conteúdo energético.

Digestibility and net energy prediction of rice by products determined with piglets / Digestibilidade e predição da energia líquida de subprodutos de arroz determinado com leitões

The aim of this study was to determine the chemical composition, digestibility, and net energy (NE) of broken rice (BRR), stabilized rice bran (SRB), and parboiled rice bran (PRB) for piglets. Two digestibility trials were performed with 12 and 18 male pigs with initial weights of 8 and 16kg, respectively. We performed total fecal collection using ferric oxide as fecal marker. The digestibility coefficients of organic matter, crude protein, and gross energy were higher (P<0.001) for the BRR compared to the SRB and PRB. The PRB presented a digestible energy 2% lower than that of BR and 5% higher than that of SRB. For BRR, average NE value was 3,228kcal/kg dry matter (DM), and the difference between the lower and higher value was 311kcal/kg DM. Average NE values of SRB and PRB were 2,896 and 3,293kcal/kgDM, respectively. The difference between the energy predicted by each equation reached 190kcal/kgDM for SRB and 285kcal/kgDM for PRB. In conclusion, BRR showed higher nutrient digestibility coefficients, except for EE and GE, which can be attributed to differences in the production processes. Regardless of the type of feedstuff tested, equations to predict NE values should be used carefully due to considerable differences in energy content.(AU)

O objetivo deste estudo foi determinar a composição química, a digestibilidade e a energia líquida (EL) da quirera (QR), farelo de arroz estabilizado (FAE) e farelo de arroz parboilizado (FAP) para leitões. Foram realizados dois ensaios de digestibilidade com 12 e 18 suínos machos com pesos iniciais de 8 e 16kg, respectivamente. A coleta fecal total foi realizada usando óxido férrico como marcador fecal. Os coeficientes de digestibilidade da matéria orgânica, proteína e energia bruta (EB) foram maiores (P<0,001) para o QR em comparação com o FAE e FAP. O FAP apresentou energia digestível 2% inferior à da QR e 5% maior que a da FAE. Para QR, o valor médio de EL foi de 3,228kcal/kg de matéria seca (DM), e a diferença entre o valor inferior e o valor superior foi de 311kcal/kg de MS. Os valores médios de EL de FAE e FAP foram de 2.896 e 3.293kcal/kgMS, respectivamente. A diferença entre a energia predita por cada equação atingiu 190kcal/kgMS para FAE e 285kcal/kgMS para FAP. Em conclusão, QR mostrou maiores coeficientes de digestibilidade dos nutrientes, exceto EE e EB, o que pode ser atribuído a diferenças nos processos de produção. Independentemente do tipo de alimento testado, as equações para prever os valores de EL devem ser usadas com cuidado devido a diferenças consideráveis no conteúdo energético.(AU)