Examination of the back fat thickness and its relationship with the cows’ age and production by Red Angus cows

Abstract

Relationship between milk production live weight and condition (applied ultrasound measurement) of Red Angus cows were examined in our experiment. Significant difference was found between the back fat thickness of the oldest (n=10) and the two young(er) groups (n=11 and 4). The age of the cows primarily effected body weight, where significant difference was found between every group. Connected with the milk production we didn’t obtain statistically demonstrable difference at any time of measurement. During the grazing period a moderately high (r=0.603) correlation coefficient was found between the back fat thickness and weight of the cows. The back fat thickness (condition) and the weight-alteration of the cows during lactation were independent - within small intervals. The relationship between the back fat thickness and the milk mass was weak and negative (r=-0.117), meanwhile the cows’ weight and the milk mass shown no connection (r=0.005). It is highly probably that the change of the beef cows’ condition was primarily influenced by the feed energy content, regardless of the energy demand of (milk) production, during lactation. Finally, regression equations for the measured variables were estimated.