The effect of lactation persistence on the milk energetic value

Abstract

The effect of lactation persistence on the milk energetic value was studied on 36 cows. The cows produced 4373 | of milk on the average. Milk samples were taken from the start to the end of lactation period every 15 days. During the experiment, 707 samples were collected and tested. The processing of statistical data made it possible to obtain the average milk energetic value of 292,8 joules, followed by standard deviation of 19,31, variation coefficient of 6,59% and variation range from 269,95 to 327,83 joules. Characteristically, the milk energetic value was steadily incerasing during the lactation, with its peaks recorded at the end of this period, which suggests a highly positive effect of the lactation on the milk energetic value.