Castrating Calves Early Is Least Stressful

Sooner is better when it comes to castrating beef calves. Scientists at the Agricultural Research Service found that calves castrated at birth suffered less stress and recovered faster than those castrated at weaning time 9 months later.

Castration is done to reduce aggressive behavior in male animals. It may also improve the taste and texture of beef. Meat from uncastrated cattle can be tougher and may carry an unpleasant odor.

Julie Morrow-Tesch and colleagues at ARS' Livestock Behavior Research Unit in West Lafayette, Ind., studied castration to gauge the stress level in beef calves that undergo it. The research aims at reducing livestock stress through a better understanding of how castration as well as other management practices affect animal behavior.

The researchers used two different castration methods--surgical and "banding." In banding, a tight rubber band placed around the animal's scrotum cuts off blood flow to the testicles. After several days, the scrotum withers and sloughs off. Cattle producers prefer this method because it's cheaper and easier than surgically removing the testicles.

The scientists compared stress levels of groups of animals castrated by either technique at birth, 33 weeks of age (about 3 weeks before weaning) or 36 weeks. All were compared against a control group of calves that were not castrated.

The researchers measured stress levels by checking the calves' blood levels of haptaglobin, a protein the liver makes when an animal is injured. In castrated calves, haptaglobin was lowest in those castrated at birth and highest in those castrated at weaning. In addition, banded calves generally showed lower levels of haptaglobin, meaning this method was less stressful than surgical castration.

The August issue of Agricultural Research magazine has a story about the research. The story is also on the World Wide Web at:

http://www.ars.usda.gov/is/AR/archive/aug98/stres0898.htm

ARS is the chief scientific agency of the U.S. Department of Agriculture.

Scientific contact: Julie Morrow-Tesch, ARS Livestock Behavior Research Unit, Poultry Science Bldg, Room 218, Purdue University, West Lafayette, IN 47907, phone (765) 494-8022, fax (765) 496- 1993,jmorrow@www.ansc.purdue.edu.