Abstract
The effect of an improved mist and fan system for dairy cows on milk production was investigated from the economical standpoint, based on three years of studies during 1985-87. When the dairy cows with an average milk yield of 20-25kg were used, the system increased by 0.66-1.90kg milk per day during the hot summer and the effect of the system was related to the environmental air temperature. From an economical viewpoint, for example, if 20 cows are treated with the system for 42 days during a hot summer and milk production increases by 1.90, 1.15 and 0.66kg per day per cow as shown in the results of Experiments 1, 2 and 3, the profits will be ¥91, 262, ¥28, 932 and ¥-12, 315 respectively, and the break-even point of the system is about 0.81kg milk production increase.
