EFFECTS OF ENSILED WET GRAPE MARC ON MILK-PRODUCTION, MILK-COMPOSITION AND BLOOD COMPONENTS OF DAIRY-COWS

Twenty multiparous Friesian cows, 60 to 120 days postpartum, were allo tted to two groups of 10 cows, according to calving date, lactation nu mber, and daily milk production, and assigned randomly to one of two d iets in a crossover design experiment. The control diet was 50% maize silage (dry basis) and 50% concentrate. The concentrate contained grou nd maize, soybean meal, wheat bran, and mineral and vitamin mix. The t reatment diet was 30% maize silage, 20% ensiled wet grape marc, 30% co ncentrate, 15% whole cottonseeds, and 5% ground maize. The diets conta ined similar quantities of crude protein, metabolizable energy, acid d etergent fibre and neutral detergent fibre. The diets were offered ind ividually, in tie-stalls, as total mixed rations in two equal proporti ons for ad libitum intakes. The cows were allowed exercise in an open lot without shade. Dry matter, metabolizable energy and crude protein intakes, milk production, milk composition and body condition score we re not affected by the diet. No differences were observed in blood ser um concentrations of glucose, total protein, albumin, urea, triglyceri des, cholesterol, Na, K, Ca, P and Mg.