Uso de ureia pós-ruminal na suplementação de bovinos Nelore durante a recria no período seco
Carregando...
Arquivos
Data
2022-02-16
Autores
Reis, Irene Alexandre
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
O objetivo desse estudo foi avaliar o efeito da suplementação com ureia pós-ruminal na alimentação de bovinos Nelore na fase de recria durante o período seco. A área de pastejo era formada pela forrageira Urochloa brizantha cv. Marandu (em média 3,5% PB e 80,7% FDN). Os suplementos proteicos foram fornecidos diariamente, na quantidade de 2 g/kg PC do animal. Os tratamentos foram: 1- CONT: Proteinado + ureia convencional (50% PB), 2- PRU: Proteinado + ureia pós-ruminal (50% PB) e 3- U+PRU: Proteinado + ureia convencional + ureia pós-ruminal (70% PB). O estudo foi dividido em 2 experimentos. No primeiro experimento: 84 bovinos Nelore, machos não castrados, 17 ± 3 meses de idade e PC médio 315 ± 84 kg, distribuídos em blocos completos ao acaso, blocados por PC. No segundo experimento: 9 bovinos Nelore castrados, 35 meses de idade e PC médio 651 ± 45 kg, fistulados no rúmen, distribuídos em triplo quadrado latino 3 × 3. No primeiro experimento, houve tendência para o consumo de suplemento entre os tratamentos (P = 0,06) com maior consumo para o tratamento CONT e PRU, houve efeito de tratamento para a taxa de desaparecimento do suplemento (P < 0,01), consumo mais rápido de suplemento para PRU e CONT, porém, o desempenho não foi influenciado pelos tratamentos (P = 0,31). No segundo experimento, não houve efeito de tratamento para o consumo de suplemento, taxa de desaparecimento, pH ruminal e N-NH3 (P ≥ 0,12), mas houve interação entre tratamento e horário de coleta para o pH (P < 0,02) e tendência para o N-NH3 (P = 0,07). Além disso, houve diferença entre os tratamentos na concentração de AGCC total, o tratamento CONT foi maior em relação aos demais e diferença na relação acetato:propionato (P < 0,02), com maior relação para os tratamentos PRU e U+PRU, foi observado tendência de tratamento (P = 0,07) para aumento na proporção molar de propionato no tratamento CONT. A suplementação com ureia pós-ruminal apresentou resultados semelhantes em relação à ureia convencional, os parâmetros ruminais, sanguíneos e o desempenho animal não foram influenciados pelos diferentes tratamentos.
The objective of this study was to evaluate the effect of post-ruminal urea supplementation in relation to conventional urea in the feeding of Nellore cattle in the growing phase during the dry period. The grazing area was formed by forage Urochloa brizantha cv. Marandu (3.7% CP and 80.7% NDF). Protein supplements were provided daily, in the amount of 2 g/kg BW of the animal. The treatments were: 1- CONT: Protein + conventional urea (50% CP), 2- PRU: Protein + post-ruminal urea (50% CP) and 3- U+PRU: Protein + conventional urea + post-ruminal urea (70% CP). The study was divided into 2 experiments. In the first one: 84 Nellore cattle, uncastrated males, 17 ± 3 months old and mean BW 315 ± 84 kg, distributed in randomized complete block (blocked by BW). In the second experiment: 9 castrated Nellore cattle, 35 months old and mean BW 651 ± 45 kg, rumen cannulated, distributed in a 3 × 3 triple Latin square. In the first, there was a trend towards supplement intake among the treatments (P = 0.06), with higher consumption for the CONT and PRU, and treatment effect for the disappearance rate of the supplement (P < 0.01), faster supplement consumption for PRU and CONT, however, performance was not influenced by treatments (P = 0.31). In the second experiment, there was no treatment effect on supplement intake and disappearance rate, ruminal pH and NH3-N (P ≥ 0.12), but there was an interaction between treatment and collection time for pH (P < 0.02) and trend for N-NH3 (P = 0.07). In addition, there was a difference between the treatments in the total SCFA concentration, the CONT treatment was higher in relation to the others and a difference in the acetate:propionate ratio (P < 0.02), with a greater relationship for the PRU and U +PRU treatments, a trend (P = 0.07) for an increase in the molar proportion of propionate in the CONT treatment was observed. Supplementation with post-ruminal urea presented similar results compared to conventional urea, rumen and blood parameters and animal performance were not influenced by the different treatments.
The objective of this study was to evaluate the effect of post-ruminal urea supplementation in relation to conventional urea in the feeding of Nellore cattle in the growing phase during the dry period. The grazing area was formed by forage Urochloa brizantha cv. Marandu (3.7% CP and 80.7% NDF). Protein supplements were provided daily, in the amount of 2 g/kg BW of the animal. The treatments were: 1- CONT: Protein + conventional urea (50% CP), 2- PRU: Protein + post-ruminal urea (50% CP) and 3- U+PRU: Protein + conventional urea + post-ruminal urea (70% CP). The study was divided into 2 experiments. In the first one: 84 Nellore cattle, uncastrated males, 17 ± 3 months old and mean BW 315 ± 84 kg, distributed in randomized complete block (blocked by BW). In the second experiment: 9 castrated Nellore cattle, 35 months old and mean BW 651 ± 45 kg, rumen cannulated, distributed in a 3 × 3 triple Latin square. In the first, there was a trend towards supplement intake among the treatments (P = 0.06), with higher consumption for the CONT and PRU, and treatment effect for the disappearance rate of the supplement (P < 0.01), faster supplement consumption for PRU and CONT, however, performance was not influenced by treatments (P = 0.31). In the second experiment, there was no treatment effect on supplement intake and disappearance rate, ruminal pH and NH3-N (P ≥ 0.12), but there was an interaction between treatment and collection time for pH (P < 0.02) and trend for N-NH3 (P = 0.07). In addition, there was a difference between the treatments in the total SCFA concentration, the CONT treatment was higher in relation to the others and a difference in the acetate:propionate ratio (P < 0.02), with a greater relationship for the PRU and U +PRU treatments, a trend (P = 0.07) for an increase in the molar proportion of propionate in the CONT treatment was observed. Supplementation with post-ruminal urea presented similar results compared to conventional urea, rumen and blood parameters and animal performance were not influenced by the different treatments.
Descrição
Palavras-chave
Desempenho, Performance, Eficiência, Metabolismo, Nitrogênio