High-tech's answer to Old MacDonald's question: How big should the barn be, Bertha? A new computer program developed at the University of Wisconsin takes a few facts about a farm animal and the weather, chews them a bit, then tells a farmer how much shelter and food the animal needs. Some of the statistical ''fodder'' required: data on the weather, an animal's size, type, and fur characteristics. Large animals, for instance, are particularly sensitive to changes in sun but not to temperature shifts. So a simple roof shelter may adequately protect a cow in winter or summer. The new program, still being tested, may help farmers with livestock breeding strategies.
A check with the computer may help farmers learn which color cattle would be best for what climates.m