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A study on lactation curves in Holstein cows in some herds in Minas Gerais, using an incomplete gamma function


, : A study on lactation curves in Holstein cows in some herds in Minas Gerais, using an incomplete gamma function. Revista Brasileira de Zootecnia 26(6): 1109-1118

2036 lactation records of Holstein cows in 122 herds in Minas Gerais, milk-recorded at monthly intervals in 1981-91, were analysed using an incomplete gamma function. Year of calving, age of cow, lactation length and herd had a significant effect on milk yield in early and late lactation and peak yield (which occurred 1.5-2.1 months after the beginning of lactation).

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