A toxin that ARS scientists identified in ponderosa pine needles causes pregnant cows to abort or deliver prematurely. The toxin is isocupressic [eye-so-cue-PRES-ik] acid. Pine-needle poisonings cause an estimated $20 million a year in losses to western beef ranchers. ARS researchers found that four of five pregnant cows that were fed two doses of the toxin a day delivered premature offspring two to eight days later. Pinpointing the culprit compound may bring scientists closer to an antidote and yield other ways to protect pregnant cows and their unborn calves. One of the questions to be addressed is whether other pine needle and bark components in isocupressic acid 's chemical family play a role in pine needle poisonings? Researchers also will find out if environmental conditions such as temperature cause toxin amounts to vary.
Poisonous Plant Research Laboratory, Logan, UT
Lynn F. James, (801) 752-2941

Controlling flies by using dung beetles has become easier, thanks to a newly published aid to identify these beneficial insects. The information will help scientists develop integrated pest management strategies for controlling fly pests. Each year, the U.S. cattle industry spends millions of dollars to control flies that breed in dung and to pay for losses in livestock weight due to biting flies. Scarab beetles of the genus Aphodius are dung feeders. They break down the dung piles and, in the process, destroy the eggs and larvae of house, horn and stable flies that breed in dung. The new guide will aid in determining species of dung beetles that are most numerous, most widely distributed and perhaps most valuable in controlling fly pests.
Systematic Entomology Laboratory, Washington, DC
Robert Gordon, (202) 382-1792

Last Updated: December 13, 1996
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