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Earlier Castration Reduces Stress

The kindest cut may be the one made at a young age, when it comes to castrating beef cattle.

Scientists in the Agricultural Research Service Livestock Behavior Research Unit at West Lafayette, Indiana, found calves castrated shortly after birth suffered less stress and recovered faster than those castrated around weaning time.

Farmers remove their calves' testicles to reduce aggressiveness in male animals as they mature. It may also improve the taste and texture of beef, says Julie Morrow-Tesch, an ARS animal physiologist/ethologist who heads the research unit. Meat from uncastrated cattle can be tougher and may carry an unpleasant odor.

The West Lafayette lab studies livestock behavior in order to gauge the stress level in animals.

"It's important to understand which management practices can be combined or should be performed independently to reduce stress in livestock,"says Morrow-Tesch. "By integrating castration prior to weaning, stress levels may be lower for calves at weaning, thereby improving animal well-being."

Morrow-Tesch used two different methods of castration --surgical and banding --on three separate groups of Angus, Simmental, and crossbred calves: Two groups were castrated and one was not. In banding, a tight rubber band around the animal's scrotum cuts off the blood supply to the testicles. After several days, the scrotum drops off. Cattle producers prefer this method because it's less expensive and not as labor-intensive as surgically removing the testicles.

Calves are usually weaned when they're 36 weeks old. The West Lafayette researchers castrated one group of animals at 36 weeks and the other at 33, which was 3 weeks before weaning. They measured the calves' stress level by checking blood levels of haptaglobin, a protein the liver makes when an animal is injured.

They found that haptaglobin levels were higher in calves castrated at 36 weeks than those castrated at 33 weeks or at birth --indicating a higher level of stress for the older animals. Surgically castrated calves also showed higher levels of haptaglobin, meaning surgical castration was more stressful than banding. --ByDawn Lyons-Johnson, Agricultural Research Service Information Staff.

Julie Morrow-Tesch is in the USDA-ARS Livestock Behavior Research Unit, Poultry Science Bldg., Room 218, Purdue University, West Lafayette, IN 47907; telephone (765) 494-8022, fax (765) 496-1993.

"Earlier Castration Reduces Stress" was published in the August 1998 issue of Agricultural Research magazine. Click here to see this issue's table of contents.