Effects of different preweaning rates of body weight gain and type of pasture during the postpartum on biological efficiency of beef cows and calves

Revista Brasileira de Zootecnia

Alves Filho, Dari Celestino⁴  Brondani, Ivan Luiz⁴  Restle, João²  Fernandes, Juliano José de Resende²  Pacheco, Paulo Santana³  Padua, João Teodoro²  Freitas, Aline Kellermann de¹ 

[1] UFRGS, Porto Alegre;UFG;UFG, Goiânia;UFSM

关键词: Charolais;    cultivated pasture;    milk yield;    native pasture;    Nellore;    total dry solids extract    Introdução Com a atual competitividade nacional e internacional no mercado da carne;    é fundamental que as propriedades priorizem o incremento da produtividade;    com maior economicidade e qualidade na produção de carne bovina;   

DOI  :  10.1590/S1516-35982007000400017

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

The objective of this experiment was to evaluate the influence of different rates of weight gain (low: 340 ± 32 g/day or moderate: 490 ± 29 g/day) of heifers, from birth until seven months of age, and the type of pasture after calving, as cows, on the biologic efficiency of cows and their calves until weaning at 217 days. After calving, the animals were maintained on native pasture (NP) or cultivated pasture (CP). During lactation, cows with low preweaning rate of weight gain showed higher milk production. Similarity between low and moderate rates of weight gain was verified for conversion of litres of milk (7.32 and 6.44 L/kg, respectively) and kg of dry matter of milk produced by cows (1.00 and 0.86 kg/kg, respectively) into kg of calves weight gain, total requirements of net energy for maintenance (maintenance plus gestation plus milk production) of cows (TOTNEm) (2733.7 and 2316.7 Mcal, respectively), TOTNEm per kg of weaned calve (14.7 and 14.7 Mcal/kg, respectively) and kg of weaned calve per 100 kg of cow at weaning (42.0 and 38.7 kg/100 kg, respectively). However, cows with low preweaning rate of weight gain weaned more kg of calves per unit of cow metabolic weight at weaning (1.89 vs. 1.73 kg/g).

【 授权许可】

CC BY-NC