Short communication: milk production and lamb development in Saint Croix and Katahdin hair sheep breeds (Ovis aries).

The aim of the present study was to characterize milk production and preweaning development of lambs from Katahdin and Saint Croix sheep. Milk production was measured weekly, from birth to 8 weeks using oxytocin technique, in 12 Katahdin (62.0 ± 5.0 kg) and 11 Saint Croix (46.2 ± 4.83 kg) multiparous ewes. The mean daily milk production for the Katahdin ewes was 1.38 ± 0.54 L/day and for the Saint Croix ewes it was 1.26 ± 0.49 L/day (P > 0.05) (mean ± SE for each group). However, more colostrum was produced immediately after parturition by the Katahdin than Saint Croix ewes (P < 0.001). The lamb's weight and weight gain were recorded weekly. The birth weight of lambs from both breeds was similar but at weaning, the Katahdin lambs were heavier (16.46 ± 0.58 kg) than the Saint Croix lambs (12.90 ± 0.59 kg) (P < 0.001). Furthermore, a significant positive correlation was found between daily milk yield and daily gain weight in both breeds, but with a greater slope in Katahdin lambs in comparison with Saint Croix lambs. It was concluded that Saint Croix and Katahdin hair sheep breeds produced similar amounts of milk during lactation, but the latter produced heavier lambs at weaning.