Age at weaning of lambs raised in an intensive production system

Abstract

Context Early weaning is an alternative that may shorten the production time, and improve growth, and carcass quality. Aims The effects of different weaning ages on growth performance and carcass characteristics of Dorper × Santa Inês lambs were evaluated. Methods Initially, 33 crossbred lactating ewes Dorper × Santa Inês with initial bodyweight (BW) of 53.16 ± 9.17 kg (mean ± s.d.) were penned individually with their lambs (nine females and 36 males; 6.59 ± 0.30 kg of initial BW and 10 ± 2.22 days of age) 10 days after birth and used in a randomised complete block design (three treatments and 11 blocks). Each pen was individually equipped with a creep feed system for the lambs. The lambs received the initial diet, and the ewes were confined and received a diet with 400 g/kg of roughage and 600 g/kg of concentrate. Lambs were weaned at ages of either 45 days (W45), 60 days (W60) or 75 days (W75). At weaning, the ewes were removed from the pens and the lambs remained in the same pen for 15 days, receiving the initial diet. After 15 days of weaning, only the males continued received the finishing diet until 165 days of life. After the finishing period, the lambs were slaughtered to measure the carcass characteristics. Key results There was no influence of weaning age on BW, body condition score, dry-matter intake, and milk production and composition of ewes. Additionally, there was no effect of treatments on the lambs‘ performance. Conclusion In an intensive production system, weaning at 45, 60, and 75 days provided similar growth performance and carcass characteristics. Implications Therefore, weaning at 45 days may be an option for farmers.