Feeding Holstein Cows Exclusively on Well Managed Tropical Grass Pastures

Abstract

A herd of Holstein cows fed exclusively on well managed tropical grass pastures in the humid mountain region of Puerto Rico completed 271 lactations over a 2-year period. An average of 3,340 liters of milk/cow/lactation was produced in the first lactation by 185 cows, 176 of which had never before been fed on grass only. The 86 cows that completed 2 lactations during the trial produced an average of 3,535 1iters/cow/lactation during the first lactation and 3,826 liters during the second lactation. The average calving interval was 395 days. Cows of low productivity during the first lactation produced markedly higher yields during their section lactation on all-grass rations, whereas the production of the initially higher yielding cows was either sustained or decreased slightly during the second lactation. These results show that cows fed only on well managed tropical grass pastures with no concentrate feeds can produce fairly high yields of milk