Revista Brasileira de Zootecnia
On-line version ISSN 1806-9290
ROSA, Gilberto Teixeira da; SIQUEIRA, Edson Ramos de; GALLO, Sarita Bonagurio and MORAES, Sofia Simões Silveira. Effect of ewe pre-partum supplementation and weaning age on performance of feedlot finished lambs. R. Bras. Zootec. [online]. 2007, vol.36, n.4, pp.953-959. ISSN 1806-9290. http://dx.doi.org/10.1590/S1516-35982007000400027.
The objective of this trial was to evaluate the effect of ewe pre-partum supplementation and weaning age on performance of lambs. Forth-four Ile de France x Bergamasca ewes that were mated with Ile de France rams were used in this trial. Animals were maintained in a rotational grazing system of Panicum maximum (cv. Tanzânia) pasture until 30 days before parturition. Ewes were then divided in two groups: supplemented (SUPL) and not-supplemented (NS); animals on the SUPL group were supplemented (1% of body weight [BW]) with a balanced diet according to NRC (1985) requirements. After parturition, both groups were supplemented. Half of lambs from the SUPL and NS groups were weaned at 45 days of age and the other half at 60 days of age. After weaning lambs were feedlot fed with a diet balanced according to NRC (1985) model. Lambs were slaughtered when they reached 30 kg of BW after 16 hours of solids fasting. Both BW and body condition score of ewes at parturition differed between SUPL and NS groups while the same was not observed at weaning. Birth weight, weaning weight, weight gain from birth to weaning and from weaning to slaughter, days in feedlot, and slaughter age all were not different in lambs born from ewes of the SUPL or NS groups. However, significant differences were observed for weaning weight and weight gain from weaning to slaughter between groups of animals weaned at 45 or 60 days of age.
Keywords : body condition; sheep; weaning; weight gain.