Whole unprocessed cottonseed was fed to lactating cows in two trials. Total concentrates were fed at 1 kg/2 kg milk in excess of 9.1 kg per cow daily. In Trial I, 18 cows were fed a control ration. Cottonseed (1.9 kg) replaced an equivalent amount of regular concentrate for 20 cows. Milk production was higher from cows fed cottonseed, but percentage of protein was lower. Cottonseed feeding did not affect percentage of fat and solids-not-fat, intake of hay, silage, regular concentrate, or dry matter. Increased intake of digestible energy accounted for 75% of the increased production. In Trial II, 18 cows were assigned to one of six Latin squares. Three rations were used: 1) regular concentrate, 2) replacement of 20% regular concentrate with cottonseed, 3) ration 2 but fed to provide energy equal to ration 1. Production of milk and solids-not-fat was highest from ration 2. Rations caused no significant differences for production of fat-corrected-milk, fat, and protein; percentage of fat and protein; efficiency of utilization of energy and protein; and intake of hay, silage, dry matter, and energy. Percentage of acetic, propionic, butyric, and valeric acid in rumen fluid was not affected by ration. © 1979, American Dairy Science Association. All rights reserved.
