USE OF WHOLE COTTON SEED AS A DIETARY-SUPPLEMENT FOR GRAZING DAIRY-COWS

In a 2-part preliminary experiment, groups of 6 and 9 Holstein-Friesia n cows in early to mid lactation were unsupplemented or supplemented w ith either 3 kg cracked sorghum grain or 3 k- whole cotton seed on a b ase pasture of irrigated pangola grass for 12 weeks or oats for 12 wee ks. The stocking rate was 5 cows/ha. Supplementation did not affect mi lk 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 s ubterranean clover at a stocking rate of 4 or 6 cows/ha and were eithe r 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 s ignificant effects on milk yield or composition. We suggest the lack o f a significant milk yield response was due to a high substitution rat e of WCS for pasture, associated with an oil content in the diet of 7. 1% of dry matter.