Level of crude protein for beef calves weaned at 66 days of age

[摘要] - The objective of this work was to evaluate the average daily dry matter intake (DMI), DMI per 100 kg of live weight (DMIP), DMI per unit of metabolic weight (DMIM), feed: gain (FG) and average daily weight gain (ADG) of beef calves fed with different levels of crude protein in the diet. Forty-seven Braford intact male calves, 66 days old and 76.4 kg of live weight were used. Animals were full fed with oat silage and concentrate (50/50), with 13; 15; 17 and 19% of CP in diet. The adaptation period to the feed and handling was 21 days. The calves were weighted after a fasting period of 14 hours, in regular intervals of 21 days across the experimental period of 84 days. Data were submitted to regression analysis. No significant relation was detected between DMI, DMIP, DMIM, FC, and ADG with the level of crude protein in the diet. The DMI, DMIP and DMIM linearly increased as the experimental period advanced, indicating the increase of the ingestion capacity with the increase of live weight. The values for ADG obtained were 644; 701; 693 and 730 g/day, for the 13; 15; 17 and 19% of CP levels, respectively. The obtained ADG were higher than to those normally obtained by calves suckling their dams and kept on native pasture or early weaned and kept on cultivated pasture.

[学科分类] 兽医学

[关键词] Braford;feed intake;growth;early weaning;weight gain;protein level;oat silage     IntroduçãoA pecuária de corte brasileira apresenta índices de produtividade baixos;quando comparados aos de países mais desenvolvidos