DRY BREWER GRAINS AS REPLACEMENT FOR ALFALFA IN DIETS FOR LACTATING EWES

Resumen

The settlement of small and medium breweries in cities leads to the production of nutrient-rich organic residues, the quick decomposition of which causes unpleasant odours and attracts large amounts of flies. Under the hypothesis that replacing alfalfa (lucerne) with dry brewer grains (DBG) for lactating ewes would modify their milk production and physicochemical quality. The aim was to determine the effect of the DBG supplementation in the feed of ewes in milk production and quality, as well as in the physical condition of the animals. Fifteen 18-month-old ewes from a cross between Friesian × Rambouillet resulting from a first birth (30 days on milk) were distributed into 3 treatments with 0, 150 or 300 g of DBG. The experiment had a duration of 30 days, in which milk production, feed intake and physicochemical characteristics of the milk (fat, non-fatty solids, density, cryoscopic point, protein, lactose, and salts) were measured and each week the intake of feed in dry mass and the change in body weight were registered. Milk production displayed no differences between treatments and a decrease was observed in the production of milk for all treatments between weeks one (462 mL) and four (162 mL). Physicochemical variables of the milk displayed no differences between treatments, and quality was not affected. The change in body weight was the highest in the 300 g DBG treatment, with a modification of approximately 12.8 ± 0.45 kg (p ≤ 0.05) during the trial time, daily weight gain was 440 ± 0.08 g d^-1 (p ≤ 0.05). The implementation of DBG in the feeds of ewes reduced the intake of dry matter, food conversion improved, and the cost of feed per ewe was reduced by up to 33.8 %.