Ewe and lamb pre-weaning performance of Pelibuey and Katahdin hair sheep breeds under humid tropical conditions

Pre-weaning is an important stage in sheep production systems focussed on meat production. In this stage, maternal ability has a key role in lamb development and productivity. The objective of this study was to evaluate the effect of breed and litter size at birth on the ewe and lamb pre-weaning performance under tropical conditions. The lambs and their dams were managed in a feedlot system during 56 days in individual pens. Milk production was estimated weekly by the weight-suck-weight method. Daily milk production (DMY), total milk production (TMY), body weight change during the lactation (BWC), litter weaning weight (LWW) and ewe weaning efficiency (EE) were estimated as ewe pre-weaning performance; and, birth weight, weaning weight at 56 days and average daily gain were estimated as lamb pre-weaning performance. Katahdin ewes produced more TMY than Pelibuey ewes (p <.001) but ewes from both breeds had similar overall LWW and EE. Pelibuey ewes had a more negative BWC than Kathadin ewes (p <.05). Katahdin lambs had greater birth weights (p <.05), but similar pre-weaning growth and live weight at weaning compared with Pelibuey lambs. Litter size effect was significant for all the traits except for BWC in both breeds. Compared to Katahdin twin-born lambs, Pelibuey twin-born lambs were lighter at birth but of similar weight at weaning. Litter size is an important factor conditioning pre-weaning performance of ewes and lambs of Pelibuey and Katahdin breeds under humid tropical conditions.Highlights Some indicators of ewe and lamb pre-weaning performance of Pelibuey and Katahdin hair sheep under tropical conditions were evaluated. The Katahdin ewes produced more milk than Pelibuey ewes, yet ewes from both breeds had similar litter weaning weight. Litter size is an important factor determining pre-weaning performance in Pelibuey and Katahdin hair sheep breeds under humid tropical conditions.