REPLACEMENT OF CORN SILAGE BY CHOPPED SUGAR CANE AND WHOLE COTTONSEED ON THE PERFORMANCE OF LACTATING HOLSTEIN COWS

Abstract

Five multiparous Holstein cows averaging 526 kg of body weight and 85 days of lactation were assigned in a 5 x 5 latin square design for the evaluation of the replacement  of corn silage by sugar cane and whole cottonseed. Cows were fed a 50:50 concentrate:forage diet (dry matter basis-DM). Treatments were defined by the replacement of corn silage by chopped sugar cane (whole plant) according to the following proportions: 100:0 (control), 75:25, 50:50, 25:75, 0:100, based on dry matter roughage. In each treatment, 0, 5, 10, 15, and 20% of whole cottonseed were added to the dietary DM, respectively. Dry matter intake (DMI) of cows fed 100, 75, and 50% corn silage diets was higher (P < 0.05) than the DMI of cows fed 25 and 0% corn silage. Milk production was higher (P < 0.05) for cows fed 100, 75 and 50% corn silage than for cows fed 25 or 0% corn silage. Milk fat concentration was higher (P < 0.05) for cows fed 50, 25 or 0% corn silage than for cows fed 100 or 75% corn silage. Milk protein concentration was not affected (P > 0.05) by inclusion of sugar cane and whole cottonseed. Corn silage can be replaced by sugar cane up to 50% of roughage level without negative effect on performance of dairy cows producing up to 18 kg milk/day.

KEYWORDS: Cottonseed, dry matter intake, milk composition, milk production.