Resumo
The objective of this study was to evaluate the relationship between ingestive behavior, temperament and residual feed intake (RFI) in Nellore cattle. Sixty-two bulls and 56 heifers after weaning, housed in individual pens, were evaluated in individual performance tests. Animals were classified as low RFI (<-0.128 kg day <->1; less than mean minus 0.5 standard deviation), medium RFI (-0.128 to 0.135 kg day <->1; ±0.5 standard deviation), and high RFI ( > 0.135 kg day <->1; greater than mean plus 0.5 standard deviation). Ingestive behavior was evaluated for 24 h by direct observation, every 24 days in bulls or every 10 days in heifers. Temperament was assessed by flight speed, reactivity in mobile confinement, composite score, and serum cortisol measurement. The most efficient animals (low RFI, 5.6 kg DM day <->1) consumed 7% less feed than animals with medium efficiency (mean RFI, 6.0 kg DM day <->1) and 13% less than the least efficient animals (high RFI, 6.34 kg DM day <->1). More feed efficient animals spent a longer time feeding and ruminating per kg of DM consumed. Similarly, more efficient animals consumed less DM per hour and ruminated less DM per hour, but made the same number of visits to the feed bunk. High-efficiency animals were 13% and 35% faster to walk 1.77 m after release from the scale than medium- and low-efficiency animals, respectively, suggesting a more reactive temperament without differences in reactivity, composite score, or serum cortisol. Feed efficiency is associated with ingestive behavior and temperament in Nellore cattle. More efficient animals consume and ruminate less feed over the same period of time than animals with medium and low feed efficiency. In addition, more efficient animals exhibit a faster flight speed and are more reactive than less efficient animals.(AU)
O objetivo deste trabalho foi avaliar a relação entre comportamento ingestivo, temperamento e consumo alimentar residual (CAR) em bovinos Nelore. Foram avaliados em teste de desempenho individual 62 machos (idade e peso inicial, 261 dias e 261±26,8 kg) e 56 fêmeas (idade e peso inicial, 293 dias e 207±19,2 kg), alojados em baias individuais. Os animais foram classificados como baixo CAR ( <-0,128 kg/dia; 0,5 desvio padrão abaixo da média; 19 fêmeas e 21 machos), médio CAR (-0,128 a 0,135 kg/dia; ±0,5 desvio padrão; 21 fêmeas e 21 machos), e alto CAR ( > 0,135 kg/dia; 0,5 desvio padrão acima da média; 16 fêmeas e 20 machos). O comportamento ingestivo foi avaliado a cada 24 dias (machos) ou a cada 10 dias (fêmeas), durante 24h, por meio de observações diretas. O temperamento foi avaliado pela velocidade de saída, reatividade em ambiente de contenção móvel, escore composto, e dosagem de cortisol sérico. Animais mais eficientes consumiram (baixo CAR; 5,60 kg MS/dia), em média, 7% menos alimento que os animais de média eficiência (médio CAR; 6,00 kg MS/dia) e 13% menos alimento que os animais menos eficientes (alto CAR; 6,34 kg MS/dia). Animais mais eficientes apresentaram maior tempo de alimentação por kg de matéria seca ingerida (P=0,03), assim como maior tempo de ruminação por kg de matéria seca ingerida (P<0,01). Da mesma forma, animais mais eficientes consumiram menor quantidade de matéria seca por hora (P=0,03) e ruminaram menor quantidade de matéria seca por hora (P<0,01), mas com mesma frequência de visitas ao cocho (P=0,18). Animais classificados como mais eficientes foram, em média, 13% e 35% mais rápidos (P=0,02) para percorrer 1,77 m logo após sair da balança, do que os animais de média e baixa eficiência alimentar, sugerindo temperamento mais reativo, sem diferenças nas variáveis reatividade em ambiente de contenção móvel, escore composto, e dosagem de cortisol sérico. A eficiência alimentar tem relação com comportamento ingestivo e com o...(AU)
Assuntos
Animais , Bovinos , Temperamento , Comportamento Alimentar , Comportamento Animal , Ingestão de Alimentos , Eficiência , Coleta de Amostras Sanguíneas/veterináriaResumo
The residual feed intake (RFI) is a parameter used in the identification of animals with respect to more efficient feed utilization. However, physiological basis are still unknown, however, the interrelationships between nutrition an immunity of the animal can contribute to the investigation of biological phenomena relevant to the RFI, since the defense system to oxidative effects caused by free radicals, is formed by acid polyunsaturated fatty acids, water soluble substances and enzymes, which derive mainly from the use of nutrients in the diet. The objective of this study was to evaluate the immunological parameters of Nellore heifers classified according to RFI. It were evaluated 176 heifers (born between 2008 and 2010), Traditional Nellore herd from Instituto de Zootecnia - Sertãozinho/SP, forming three groups of evaluation, submitted to test post weaning feed efficiency and classified into high (> mean + 0.5 SD, n= 55), medium (± 0.5 SD, n= 65) and low RFI ( mean 0.5 SD, n= 56). The diet was formulated based on Brachiaria decumbens hay, corn, cottonseed meal and mineral mixture (45:55, forage: concentrate). The weight of the animals were performed in fasting blood samples collected by venipuncture vein, using tubes of 10 ml type vacuntainer with EDTA anticoagulant. In the clinical laboratory, we measured the values of leukocytes (LEU); Targeted (SEG) and lymphocyt
O artigo não apresenta resumo em português.
Resumo
The reactivity is an important behavioral trait that is directly linked to the economic characteristics of beef. Less reactive animals have better performance and efficiency, thus, this study aimed to evaluate the influence of reactivity in the animals´ classification for residual feed intake (RFI). The study was conducted at Centro APTA Bovinos de Corte Instituto de Zootecnia -Sertãozinho/SP. Sixty males belonging to the Traditional Nelore herd were classified into high (> mean + 0.5 SD, n = 21), medium (±0.5 SD from mean, n = 20) and low RFI ( mean - 0.5 SD, n = 19) . The animals had, on average, 256 kg and 264 days, respectively, for weight and age. They were housed in individual pens for 112 days, being 28 for adaptation to facilities and diet and 84 days for data collection. The diet was composed by Brachiaria hay, corn, cottonseed meal and mineral supplement and was offered to the animals twice a day, with ad libitum access to diet and water. The RFI was calculated as the difference between observed and predicted intake by a multiple regression equation, which considers the average daily gain and metabolic body weight. To measure the temperament, blood samples were collected from the animals´ jugular vein and analyzed to quantify serum levels of cortisol. The composite score (CS) was done by a trained observer, giving scores from 1 to 5 for the general movement of
O artigo não apresenta resumo em português.
Resumo
The residual feed intake (RFI) is a parameter used in the identification of animals with respect to more efficient feed utilization. However, physiological basis are still unknown, however, the interrelationships between nutrition an immunity of the animal can contribute to the investigation of biological phenomena relevant to the RFI, since the defense system to oxidative effects caused by free radicals, is formed by acid polyunsaturated fatty acids, water soluble substances and enzymes, which derive mainly from the use of nutrients in the diet. The objective of this study was to evaluate the immunological parameters of Nellore heifers classified according to RFI. It were evaluated 176 heifers (born between 2008 and 2010), Traditional Nellore herd from Instituto de Zootecnia - Sertãozinho/SP, forming three groups of evaluation, submitted to test post weaning feed efficiency and classified into high (> mean + 0.5 SD, n= 55), medium (± 0.5 SD, n= 65) and low RFI ( mean 0.5 SD, n= 56). The diet was formulated based on Brachiaria decumbens hay, corn, cottonseed meal and mineral mixture (45:55, forage: concentrate). The weight of the animals were performed in fasting blood samples collected by venipuncture vein, using tubes of 10 ml type vacuntainer with EDTA anticoagulant. In the clinical laboratory, we measured the values of leukocytes (LEU); Targeted (SEG) and lymphocyt
O artigo não apresenta resumo em português.
Resumo
The objective of this study was to evaluate the relationship between ingestive behavior, temperament and residual feed intake (RFI) in Nellore cattle. Sixty-two bulls and 56 heifers after weaning, housed in individual pens, were evaluated in individual performance tests. Animals were classified as low RFI ( 0.135 kg day
O objetivo deste trabalho foi avaliar a relação entre comportamento ingestivo, temperamento e consumo alimentar residual (CAR) em bovinos Nelore. Foram avaliados em teste de desempenho individual 62 machos (idade e peso inicial, 261 dias e 261±26,8 kg) e 56 fêmeas (idade e peso inicial, 293 dias e 207±19,2 kg), alojados em baias individuais. Os animais foram classificados como baixo CAR ( 0,135 kg/dia; 0,5 desvio padrão acima da média; 16 fêmeas e 20 machos). O comportamento ingestivo foi avaliado a cada 24 dias (machos) ou a cada 10 dias (fêmeas), durante 24h, por meio de observações diretas. O temperamento foi avaliado pela velocidade de saída, reatividade em ambiente de contenção móvel, escore composto, e dosagem de cortisol sérico. Animais mais eficientes consumiram (baixo CAR; 5,60 kg MS/dia), em média, 7% menos alimento que os animais de média eficiência (médio CAR; 6,00 kg MS/dia) e 13% menos alimento que os animais menos eficientes (alto CAR; 6,34 kg MS/dia). Animais mais eficientes apresentaram maior tempo de alimentação por kg de matéria seca ingerida (P=0,03), assim como maior tempo de ruminação por kg de matéria seca ingerida (P<0,01). Da mesma forma, animais mais eficientes consumiram menor quantidade de matéria seca por hora (P=0,03) e ruminaram menor quantidade de matéria seca por hora (P<0,01), mas com mesma frequência de visitas ao cocho (P=0,18). Animais classificados como mais eficientes foram, em média, 13% e 35% mais rápidos (P=0,02) para percorrer 1,77 m logo após sair da balança, do que os animais de média e baixa eficiência alimentar, sugerindo temperamento mais reativo, sem diferenças nas variáveis reatividade em ambiente de contenção móvel, escore composto, e dosagem de cortisol sérico. A eficiência alimentar tem relação com comportamento ingestivo e com o...
Assuntos
Animais , Bovinos , Comportamento Alimentar , Comportamento Animal , Ingestão de Alimentos , Temperamento , Coleta de Amostras Sanguíneas/veterinária , EficiênciaResumo
The reactivity is an important behavioral trait that is directly linked to the economic characteristics of beef. Less reactive animals have better performance and efficiency, thus, this study aimed to evaluate the influence of reactivity in the animals´ classification for residual feed intake (RFI). The study was conducted at Centro APTA Bovinos de Corte Instituto de Zootecnia -Sertãozinho/SP. Sixty males belonging to the Traditional Nelore herd were classified into high (> mean + 0.5 SD, n = 21), medium (±0.5 SD from mean, n = 20) and low RFI ( mean - 0.5 SD, n = 19) . The animals had, on average, 256 kg and 264 days, respectively, for weight and age. They were housed in individual pens for 112 days, being 28 for adaptation to facilities and diet and 84 days for data collection. The diet was composed by Brachiaria hay, corn, cottonseed meal and mineral supplement and was offered to the animals twice a day, with ad libitum access to diet and water. The RFI was calculated as the difference between observed and predicted intake by a multiple regression equation, which considers the average daily gain and metabolic body weight. To measure the temperament, blood samples were collected from the animals´ jugular vein and analyzed to quantify serum levels of cortisol. The composite score (CS) was done by a trained observer, giving scores from 1 to 5 for the general movement of
O artigo não apresenta resumo em português.