Transgenic pigs expressing bovine growth hormone had lower appetites,
enlarged organs, gastric ulcers, and other health problems.
Pig (Sus domesticus).
Bovine growth hormone (bGH) gene, with expression controlled by the mouse
Goal of This Study:
Compare the growth and overall health of pigs expressing bovine growth
hormone with their non-transgenic siblings.
The transgenic animals gained weight 10-15% more quickly than their
Despite their faster growth rate, the transgenic pigs ate 10-20% less.
According to the authors, appetite suppression is also observed in pigs
receiving growth hormone by injection.
The weights of the heart, liver, kidneys, and adrenals in the transgenic
pigs all increased relative to their total body weight.
Autopsies were conducted on 5 transgenic and 3 non-transgenic pigs.
Five out of 5 transgenic pigs had gastric ulcers, 4 out of 5 suffered from
joint inflammation, and 4 out of 5 had enlarged nuclei in cardiac cells.
None of the 3 non-transgenic pigs displayed these symptoms.
The authors noted that the transgenic pigs were lethargic and
uncoordinated, and the boars lacked libido.
Pursel, V. G., C. A. Pinkert, K. F. Miller, D. J. Bolt et al. (1989).
"Genetic Engineering of Livestock," Science vol. 244, pp. 1281-8.
USDA Agricultural Research Service, Beltsville, MD; University of
Pennsylvania, Philadelphia; University of Washington, Seattle.
National Institutes of Health, U.S.
Not on the market as of 2009.
Copyright 2009 The Nature