Newborn Pigs for Faster Weight Gains
By Ben Hardin
June 18, 2001
Newborn pigs may get off to a better
start if given a one-time injection of an anti- inflammatory agent used in
veterinary and human medicine. In repeated small-scale tests, pigs treated with
dexamethasone grew about 12 percent faster in their first 18 days of life than
did other pigs.
Dexamethasone is a synthetic version of a type of hormone called a corticoid
that is naturally produced by animals under stress.
Agricultural Research Service animal
physiologist Jeffery A. Carroll and his colleagues at the
University of Missouri-Columbia now are
beginning to test the one-time treatments long-term effects on pigs.
These tests include measures of body composition at market weight, rate of
weight gain and the amount of feed consumed per pound of gain.
Reducing the average time from birth to market by just one day could
translate into an annual income boost of tens of millions of dollars for the
nation's swine producers, says ARS animal physiologist Robert L. Matteri,
formerly at Columbia.
If treated pigs faster growth persists, a pharmaceutical company might
be interested in conducting additional tests. More tests would be needed in
order for the company to apply for federal regulatory approval of dexamethasone
injection as a treatment to enhance pigs growth.
Injected at the wrong time, dexamethasone could slow a pigs growth,
according to Carroll. The first hour after birth may be an opportune time to
apply the synthetic stress hormone to program the pigs endocrine systems
for lifetime efficient weight gain. In the experiments, pigs injected with the
drug experienced no obvious behavioral effects and they started to nurse
Carroll decided to research dexamethasone after earlier experiments had
provided insights on lasting effects of stress at birth. In those studies, he
measured natural hormone and chemical levels of young pigs, some of which had
been delivered by caesarian section. He concluded that, by preventing the
stress of natural birth, surgical birth inhibited the pigs' growth.
ARS is the U.S. Department of
Agricultures chief scientific agency.
Scientific contact: Jeffery A. Carroll, ARS
Physiology Research Unit, Columbia, Mo., phone (573) 882-6261, fax (573)