Dairy cows cooling

MISTING AND DAIRY COWS

Cattle without water misting have a physiological and behavioral stress response to heat which negatively affect onbehavior, physiology, performance, and carcass traits.

Studies have found that at temperatures as low as 79°F, dairy cows will begin to cut feed intake and lose body weight. Milk production falls. Reproductive performance, health, and lactational performance are affected. Heat stress will continue to affect performance even in the cooler months ahead. High yielding cows are most susceptible to heat stress. All of this quickly impacts your pocket book!
The degree of heat stress suffered by the cow will depend on the combination of environmental conditions – air temperature, relative humidity, air movement, and radiation from the sun. Dairymen use shades, fans, and ample fresh drinking water to help herds beat the heat; but often shade and ventilation are just not enough. In southern states, where heat and humidity are more severe, dairymen have also used sprinklers to provide added cooling effects. Research has shown that intermittent misting in combination with shade and forced air movement is a very effective method of cooling diary cows, thereby reducing the production losses experienced during hot humid weather conditions. By using a high pressure, misting nozzles, enough water can be applied to fully cool the cows to the hide. The water is then allowed to evaporate, which pulls heat from the air and the animal, just like sweating. Increased air movement provided by fans, makes this system most efficient.

These results indicate that cooling cows with water applied through either a mist or spray can increase milk production if the system is installed properly. Overall, the combination of mister and fan cooling system provided the best choice in several studies, because water use and waste-waterrunoff were reduced compared tostandard spray system.

Effects of ventilation and misting on behaviour of dairy cattle in the season in south Italy: Milk Yield kg/head/day +4kg/day

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org Citation: Pp. 303-311 in Fifth International Dairy Housing Proceedings of the 29-31 January 2003 Conference (Fort Worth, Texas USA) 701P0203. Authors: F. Calegari, L. Calamari and E. Frazzi
This research evaluated the effectiveness of the ventilation and misting equipment on three farms with Italian Friesian cows in the South of Italy. This research was carried out in the hotter period (May – September) during two consecutive years.
At each farm there were two homogeneous groups of animals with respect to production, number of calving and lactation phase The first group was raised in a pen with environmental conditioning system limited to the feeding area and carried out with the use of ventilation and misting (FM). The second group, which was the control group (C), was not conditioned. The micro-climatic parameters (temperature and relative humidity) were recorded continuously at each farm by electronic probes which were put at animal height and connected to a data logger. Weekly individual measurements were performed on milk yield and behavior observing the animals in different areas two times a day. The difference in milk yield between C and FM group ranged between 1-3 kg/head/day and, in the hottest period, ranged between 2-4 kg/head/day. Animal behavior changed as the climatic conditions varied. On average, in the conditioned pen, we noticed higher values in the rate of standing animals in the feeding area (18.6 % in FM vs. 12.9% in C) and lower values in the rate of lying animals in
the resting area (31.3% in FM vs. 34.0% in C). These results show the value of the treatment with the use of ventilation and misting of water.