Produção de leite de vacas mestiças mantidas em pastagens de campi-elefante e capim-tanzânia em São Paulo

The aim of this study was to evaluate some agronomic characteristics of elephant grass cv. Guacu and tanzania guinea grass, during four grazing cycles, in two consecutive years, and the milk yield of crossbred cows grazing in rotation on the two areas. The grazing method was rotational grazing system. For the 1st and 2nd years, the results for elephant grass were 7,781 and 5,321kg of DM ha-1 of FM pre grazing and 2,658 and 2,730kg of DM ha-1 of residual mass, respectively. Considering the grazing cycles, no difference was observed for FM pre grazing for the 1st year but it was different for the 2nd year. The results for the 1st year were 7,715; 7,678; 8,534 and 7,510kg of DM ha-1 and 2nd year were 6,358; 4,727; 5,548 and 4,133kg of DM ha-1 of pre grazing FM for 1st 2nd 3rd and 4th grazing cycles, respectively. For Tanzania guinea grass, the averages were 5,000 and 5,384kg of DM ha-1 of pre grazing FM and 2,287 and 2,819kg of DM ha-1 of residual mass for the 1st and 2nd years respectively. There was difference for grazing cycles on pre grazing FM in the two studied years. The results for the 1st years were 5,501; 5,825; 5,631 and 4,382kg of DM ha-1 of pre grazing FM and in the 2nd year were 5,411; 6,000; 5,736 e 4,068kg of DM ha-1 of pre grazing FM for 1st 2nd 3rd and 4th grazing cycles, respectively. No difference was observed in daily milk production, and the average per cow was 10.7 and 10.6kg in elephant grass and 10.8 and 10.1kg in Tanzania grass, respectively. The coefficient of correlation between milk production and percentage of leaves in FM was 0.77 and between milk production and percentage of leaves in residue was 0.61.