Semi-early weaning significantly boosts milk yield in Sicilo-Sarde ewes without compromising milk quality

Optimizing milk production in dairy sheep is crucial for farmer profitability, yet balancing lamb growth with ewe milk yield for market remains a challenge. Traditional weaning practices can impact both the quantity and quality of milk available for sale, as well as the ewe's mammary health and subsequent lactation cycles. Understanding how different weaning periods affect milk yield, milk composition, and udder morphology is essential for developing efficient and sustainable sheep farming strategies. This study addresses the need for evidence-based weaning protocols to maximize marketable milk volume without negatively affecting milk quality or ewe physiology.

Seventy-two early-lactation Sicilo-Sarde ewes, averaging 4.28 ± 0.77 years old, were divided into three groups based on weaning system (WS). Lambs were weaned at 30-35 days for early weaning (EW), 45-50 days for semi-early weaning (SEW), and 60-70 days for late weaning (LW). Four milk recordings were conducted during the first 45 days of milking (at days 7, 15, 30, and 45). Residual milk (RM) was collected after an oxytocin injection. External mammary morphology was assessed using six linear measurements and three udder and teat scores to evaluate physical changes.

Weaning system (WS) significantly affected (p < 0.05) both milked yield (MM) and total milk yield (MY). However, residual milk (RM) was not significantly affected (p > 0.05) by the weaning strategy. Notably, SEW and LW ewes consistently produced more MM and MY than EW ewes throughout the study period. Furthermore, MM, RM, and MY traits were influenced by the ewes' overall milk production level. Milk composition for both MM and RM generally did not vary with WS (p > 0.05), with one exception: > The lactose percentage was significantly higher (p < 0.05) in the RM of the SEW and LW groups. Regarding mammary morphology, WS only influenced udder height, cistern height, and teat diameter at the base (p < 0.05). Udder traits and teat diameter showed significant moderate correlations with all milk traits (p < 0.05; r = 0.27-0.39).