gm-pig/report-1
Transgenic pigs expressing bovine growth hormone had lower appetites, enlarged organs, gastric ulcers, and other health problems.
Manipulated Organism: Pig (Sus domesticus).
Inserted Transgenes: Bovine growth hormone (bGH) gene, with expression controlled by the mouse metallothionein promoter.
Goal of This Study: Compare the growth and overall health of pigs expressing bovine growth hormone with their non-transgenic siblings.
Intended Effect: The transgenic animals gained weight 10-15% more quickly than their non-transgenic siblings.
Unintended Effects:
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.
Source: 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.
Author Affiliations: USDA Agricultural Research Service, Beltsville, MD; University of Pennsylvania, Philadelphia; University of Washington, Seattle.
Funding: National Institutes of Health, U.S.
Product Status: Not on the market as of 2009.
Copyright 2009 The Nature Institute.
This document: http://natureinstitute.org/nontarget/gm-pig/report-1