Milk production in Brahman and Angus cows on endophyte-infected fescue and common bermudagrass.

Daily milk yield and milk fat were estimated by method of milking machine in 60 Angus and 60 Brahman cows grazing common bermudagrass or endophyte-infected fescue during a 3-yr period. Averaged over monthly estimates, there was evidence (P < .05) of a dam breed x forage interaction in daily milk yield. Tall fescue decreased milk yield more in the Angus (1.64 kg/d, P < .01) than in the Brahman (.53 kg/d, P > .15). There were significant dam breed effects on both percentage of milk fat and daily milk fat yield; Brahman exceeded Angus by .68% (P < .01) and 34.3 g/d (P < .01), respectively. There were significant forage effects for both percentage of milk fat and daily milk fat yield; common bermudagrass exceeded tall fescue by .5% (P < .01) and 62.3 g/d (P < .01), respectively. These data indicate that incorporation of Brahman germplasm into a grazing system that uses endophyte-infected fescue may be beneficial in daily milk yield but will probably not prevent decreases in milk fat production associated with grazing endophyte-infected tall fescue.