Shade Options for Grazing Cattle
University of Kentucky Cooperative Extension Service , AEU-91 , 2000
Dairies in Kentucky lose more in milk production from heat stress as opposed to cold stress. Beef herds can also benefit from shade structures to reduce heat stress, thus improving feed efficiency and reproduction. Particularly in bef operations where fescue-based pastures with high-endophyte fescue are used, shade is a must! In other situations, the need for shade must be balanced against the tendency for animals to congregate under the shade and thereby reduce feed intake. Research data are limited as to the benefit of shade. In one study in Arizona, shade improved milk production by 7.5 % when placed over the feed bunk as compared to a control situation with no shade. In Kentucky, even more benefit should be obtained, since much higher humidities are common, and possibly less night cooling is available. Recent research conducted on UK’s Animal Research Center farm indicated that beef cows and calves showed improved gains with shade in Spring and early Summer heat stress periods (an increase of 1.25 lb/day for cows, 0.41 lb/day for calves in a May measurement period with heat stress on endophyte infected fescue). In addition, deep body temperatures during the Spring period appeared to be 0.5 to 1.4 oF higher for non-shaded cattle as opposed to shaded animals. Based upon this study, the results suggested that if adequate shade is not present in the hotter summer period, no shade at all may be better than a limited shade amount. Limited shade may actually be a detriment to performance and well-being, as animals crowd under the small shades and reduce their cooling potential. For pasture situations, producers should strongly consider providing shade for dairy cows in most situations during the summer, and probably also for beef breeding stock. For stocker animals, the value is more questionable, except in the case of animals grazing on high-endophyte fescue.