Abstract 244

Jerez,I; Menchaca,-MA; Rivero,-JL

Inst. Ciencia Animal, Apartado 24, San Jose de las Lajas, Havana, Cuba.

Cuban-Journal-of-Agricultural-Science. 1986, 20: 3, 231-237; 31 ref.

During 2nd and 3rd lactation 90 Holstein-Friesian cows in 3 groups grazed on fertilized and irrigated Coast cross 1 Bermuda grass (Cynodon dactylon), star grass (Cynodon nlemfuensis) or pangola grass (Digitaria decumbens) at 3, 4 or 5 cows per ha. Concentrates were offered in lactation weeks 1-10 at 0.5 kg/kg milk above 5 kg/day. In both lactations there was a significant effect on milk yield per cow and per ha of the interaction between pasture type and stocking rate, with milk yield per cow tending to be higher on Bermuda grass and pangola grass at lower stocking rates but highest on star grass at the highest stocking rate. Thus, as stocking rate increased, milk yield per ha of star grass increased from 9352 to 18 133 kg in 2nd lactation and from 7976 to 17 244 kg in 3rd lactation compared with much smaller increases from about 11 500 to 14 440 and 13 113 kg in 2nd lactation and from 9585 and 9118 to 15 310 and 14 077 kg in 3rd lactation on Bermuda grass and pangola grass resp.