Efeito Da Época Da Desmama E Da Pastagem No Desempenho De Vacas E Terneiros De Corte. 1 - Desempenho Das Vacas

Abstract

RESUMO Foi avaliado o desempenho de vacas de corte desterneiradas antecipadamente, aos 101 dias após o parto, e que no período anterior ao desterneiramento haviam permanecido em campo nativo (CN) ou pastagem cultivada (PC) e após o desterneiramento, em CN. Foi mantido ainda um grupo de vacas em CN desterneiradas aos 213 dias, seguindo o método de criação normalmente empregado na região. Considerando todo o período experimental, foi verificado um maior ganho de peso (P < 0,01) e melhor estado corporal (P < 0,05) nas vacas cujo desterneiramento precoce foi precedido pela alimentação em PC. A taxa de aparecimento de cio pós-parto, foi de 100% nas vacas desterneiradas aos 101 dias e mantidas previamente em PC, 41,7% para as vacas desterneiradas antecipadamente e que permaneceram em CN, e de 14,3% naquelas desterneiradas aos 213 dias.

Effects of the weaning age of calves on somatic development and on reproductive performance of beef cows

“…These results are consistent with those obtained by , Moojen et al (1994), Simeone & Lobato, (1996); Restle et al (2001), and Almeida et al (2002), who found that cows submitted to early weaning presented higher pregnancy rates as compared to conventionally-weaned cows.…”

“…The higher weight gain and the better body condition of cows whose calves were submitted to early weaning have a direct effect on their subsequent reproductive performance (Moojen et al, 1994;Simeone & Lobato, 1996;Lobato et al, 2000;Restle et al, 2001;Almeida et al, 2002).…”

“…The authors conclude focusing on the importance of cow body weight and body condition at weaning, because, when negatively influenced by previous poor nutritional management (cows in that study grazed on low availability native pastures, with 730.5 kg DM/ha), reproductive performance is compromised. Under excessive stocking densities, which determine lower forage availability and consequent lower body weight, cows present low reproductive indexes (Moojen et al.1994;Simeone & Lobato, 1996;Fagundes et al, 2003).…”

“…The lack of proper management practices and excessive stocking rates reduce weight gain resulting in low pregnancy rates (Moojen et al, 1994;Quadros & Lobato, 1996;Gottschall & Lobato, 1996;Simeone & Lobato, 1996;Fagundes et al, 2003). Costa et al (1981) and Pötter & Lobato (2004) showed that productive and reproductive indexes can be improved by introducing cultivated pastures in beef production systems but the use of these kind of pastures may not be practical or economically feasible for breeding herds in most commercial beef systems (Restle et al, 1998).…”

“…The aim of early weaning is to make cows recover their body weight and body condition -even when submitted to feed restriction -thereby improving their reproductive efficiency (Moojen et al, 1994;Pascoal & Vaz, 1997;Restle et al, 2001;Fagundes et al, 2003;Almeida & Lobato, 2004).…”