Effects of levels of nitrogen on the milk production of cows in coast-cross pasture

Abstract

The purpose of this work was to evaluate the effects of three levels of nitrogen (N), 100, 250 and 400 kg/ha/year, applied in coast-cross (Cynodon dactylon (L.) Pers.) pasture on the milk production of Holstein cows during two lactation periods. The pasture was irrigated in dry season and used by rotational grazing. The experimental design was in randomized blocks, in split plots (plot = level of N; split plot = period of lactation), with two pasture replications and eight cows per treatment. The crude protein contents were similar (P > 0.05) in the treatments. The stoking rates of pasture was lowest (P < 0.05) in the lowest level of N. The milk production per day and per animal were similar (P < 0.05) in the treatments. The milk productions per area were higher (P < 0.05) in two highest levels of N. The milk production per kg of N applied was highest in the level of 100 kg/ha/year.