EFFECTS OF DRY CORN GLUTEN FEED ON MILK-PRODUCTION AND BLOOD COMPONENTS OF DAIRY-COWS

Twenty multiparous Friesian cows, 80 to 110 days postpartum, were allo tted to two groups of 10 cows according to calving date, lactation num ber, and daily milk production and were assigned randomly to one of tw o diets in a crossover design experiment. The control diet was 45% cor n silage (dry basis), 15% whole cottonseeds, and 40% concentrate. The concentrate contained ground corn, wheat bran, soybean meal, and miner al-vitamin mix. Dry corn gluten feed was 20% in the treatment diet, re placing an equal proportion of concentrate. The two diets contained si milar quantities of crude protein, net energy for lactation, neutral d etergent fiber and acid detergent fiber. The diets were offered indivi dually as total mixed rations in two equal portions at 09:00 and 20:00 h in amounts to achieve nn libitum intake. The two groups of cows wer e allowed exercise in an open lot without shade from 11:00 to 16:30 h and 22:00 to 05:30 h. The cows were milked daily at 06:00 and 17:00 h. The dry matter, net energy for lactation, and crude protein intakes w ere not significantly affected by the addition of dry corn gluten feed to diet. Milk production and milk composition were not affected by di et. No differences were observed in blood serum concentrations of gluc ose, total protein, albumin, urea, triglycerides, cholesterol, phospho lipids, Na, K, Ca, P, Mg, and Cl. Results of this study indicate that corn gluten feed will support similar levels of milk production and co mposition when used to replace a portion of the concentrate fed to lac tating dairy cows.