On the milk ejection mechanism in cows upon an increase in one-time milk yield

Sympathetic nervous system regulates milk flow through the udder duct system. However, the mechanisms of contraction of the alveoli upon accumulation of different amounts of milk in the udder have not been studied. In the paper, it is found for the first time that the excretion of an increased amount of milk is accompanied by a change in the parameters of the udder blood supply caused by an increase in the contractile response of the alveolar complex. Thus, the goal of the paper is to investigate the contractile reaction of the alveolar complex and lactation in cows with an increased single-milking yield. Nine black-and-white dairy cows of the 2-5th calving were tested, 7 times each, in the first half of lactation (All-Russian Scientific Research Institute of Physiology, Biochemistry and Nutrition of Farm Animals, Kaluga Province). A serial ADU-1 milking machine and a counter sensor (Latvia) were used to record milking parameters. The single-milking yield ranged from 3.4 to 6.7 kg in the control period and was 24.5 % higher (p function show_eabstract() { $('#eabstract1').hide(); $('#eabstract2').show(); $('#eabstract_expand').hide(); }