With winter fast approaching, dairy farmers who want to avoid unnecessary calf losses would do well to consider where they are housing them, a Utah State University research animal scientist said.

"Experimental and clinical research have indicated that environment does play a major role in exposure, infection and perpetuation of disease in calves," said Ann S. Macaulay, USU research animal scientist with the U.S. Department of Agriculture Research Service.Just as summer's extreme heat can stress an animal, so can the extreme cold of winter. These excesses can influence disease resistance of dairy calves, Macaulay said.

Yearly industry death losses in dairy calves range from 7 percent to more than 20 percent, representing a major loss to the dairy industry, she said.

John Swain, instructor over the dairy herdsman program at the USU Caine Dairy Teaching and Research Center, said the dairy farm has significantly reduced death loss through using calf hutches. He said the hutches not only protect the calf against extreme temperatures, but also isolate the animal to help minimize the spread of bacterial and viral diseases.

The effectiveness of separating calves was demonstrated by Ronald L. Bowman, USU Extension Service dairy cattle nutrition and management specialist.

He participated in a two-year dairy technical assistance program in Ecuador in 1986 where he worked with some 30 dairy farmers. Previously, he said, calf losses averaged 25 to 40 percent. That number was reduced by 38 percent in some cases simply by removing the calves from enclosed barns where they were housed together.

Isolating the animals and improving their environment and nutrition greatly reduced the spread of respiratory diseases.

"Hutches helped tremendously," he said. "They acted like isolation units."

Swain said pre-built plastic dome hutches can be purchased for about $250. To save money, he said wooden hutches can be built for $80 to $100 apiece.

He said dairy farmers who choose not to use hutches should provide dividers where the animals are housed to prevent physical contact and the consequent spread of bacterial and viral diseases.

Equally important is ventilation. He said airborne bacteria can lead to several respiratory troubles, a common cause of death among calves.

For more information regarding the construction of calf hutches, contact a USU county Extension agent.