Relationship between different sources of non-protein nitrogen and supplementation times on performance and metabolism of grazing Nellore cattle during the dry season

Autor(es)

Mota, Veronica A. C. ; Prados, Laura F. ; Nascimento, Keuven S. ; Fernandes, Rodolfo M. ; Silva, Luiz F. Costa E. ; Holder, Vaughn B. ; Pettigrew, James E. ; Resende, Flavio D. ; Siqueira, Gustavo R.

• Tipo de documento: Artigo Científico
• Fonte: TROPICAL ANIMAL HEALTH AND PRODUCTION; v. 54, n. 6, p. 12-pg., 2022-12-01.

Resumo

Two experiments were conducted to evaluate the effect of supplementation with two sources of non-protein nitrogen at different feeding times on the performance, ingestive behavior, and rumen metabolism of growing Nellore bulls during the dry season. Exp. 1: One hundred and twenty Nellore bulls, weighing 206 +/- 39 kg of initial body weight (BW) and 12 months of age, were divided into 20 paddocks, and they were used in randomized block design in a 2 x 2 factorial arrangement to evaluate performance and ingestive behavior. Exp. 2: 12 rumen cannulated animals with 509 +/- 59 BW, divided into 4 paddocks, were used in a triple Latin square 4 x 4 in a 2 x 2 factorial arrangement to evaluate metabolism. The factors were 2 non-protein nitrogen sources (urea or slow-release urea) and 2 feeding times (07:00 or 13:00 at 4 g/kg BW of supplement). There was no influence of non-protein sources, supplementation time, or their interaction on the grazing time or the trough time during daytime, nighttime, or total (P >= 0.16). There were no interactions or factor effects on ADG (P >= 0.45) or final body weight (P >= 0.39). There was an interaction between supplementation time and collection time (P < 0.01) on ruminal pH. Animals supplemented in the morning had greater total SCFA at 18 h after supplementation (P = 0.03). The supplementation time and the non-protein nitrogen sources did not alter the ingestive behavior or animal performance of young Nellore cattle. (AU)

• Processo FAPESP: 16/05131-4 - Estratégias para aumento da eficiência de utilização do nitrogênio na fase de recria de bovinos nelore em pastagens
• Beneficiário: Verônica Aparecida Costa Mota
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 17/50339-5 - Plano de desenvolvimento institucional de pesquisa do Instituto de Zootecnia (PDIp)
• Beneficiário: Lenira El Faro Zadra
• Modalidade de apoio: Auxílio à Pesquisa - Programa Modernização de Institutos Estaduais de Pesquisa
• Processo FAPESP: 18/20176-0 - Impacto de diferentes estratégias de suplementação em novilhas Nelore sobre o desempenho nutricional e reprodutivo
• Beneficiário: Laura Franco Prados
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado