Use of whole cotton seed as a dietary supplement for grazing dairy cows

Abstract

In a 2-part preliminary experiment, groups of 6 and 9 Holstein-Friesian cows in early t o mid lactation were unsupplemented or supplemented with either 3 kg cracked sorghum grain or 3 kg whole cotton seed on a base pasture of irrigated pangola grass for 12 weeks or oats for 12 weeks. The stocking rate was 5 cows/ha. Supplementation did not affect milk yield or composition. In a second experiment a group of 20 Holstein- Friesian cows in early to mid lactation grazed on a base pasture of subterranean clover at a stocking rate of 4 or 6 cows/ha a n d w e r e either unsupplemented or supplemented with 3 kg of whole cotton seed (WCS) over 12 weeks. Milk yield averaged 20.3 kg/cow.day and there were no significant effects on milk yield or composition. We suggest the lack of a significant milk yield response was due to a high substitution rate of WCS for pasture, associated with an oil content in the diet of 7.1 % of dry matter.