Wine by-products feeding on ewe physiological traits, milk quality and the meat quality of their suckling lambs
Winery by-products, which may constitute undesirable waste, can be used as feeding supplements in ruminants, but they could modify product quality. Aim - To investigate the effect of wine by-products added to lactating ewes feeding on the ewe's welfare, milk quality and their suckling lamb performance, carcass and meat quality. Material and methods - A total of 42 Chamarita breed ewes were allocated in one of three experimental diets: a control, based in concentrates without added by-product, and diets supplemented with either 10% grape pomace or 5% grape seed on a dry matter basis, during middle gestation and lactation. Ewe's physiological welfare indicators and milk quality were assessed, and daily gain, carcass and meat quality (pH, cooking and thawing losses, texture and colour) in their suckling lambs were analysed. Results and discussion - Compared to the control group, cortisol levels was higher in the ewes fed pomace; whereas creatine kinase and non-esterified fatty acids were superior in the ewes fed seed. However, milk composition was minimally affected, showing less lactose concentration the grape pomace and control groups, but the percentage of fat and protein and somatic cell count was similar between treatments. The suckling lambs showed similar performance, but the fattening carcass score of the lambs of the grape seed group was lower than control. The meat of the three treatments reached a similar pH, cooking loss and instrumental texture and only a minor effect in thawing loss and the colour parameter lightness was observed. Conclusion - The inclusion of grape by-products may be used as a supplementation in lactating ewes without compromising lambs' growths, carcass composition and instrumental meat quality.