CSIRO Science Image

Typically transgenic sheep expressing the extra growth hormone gene grow larger than normal sheep, are leaner, produce more milk and, in some breeds, produce more wool. A sheep has approximately 45,000 genes. CSIRO research indicates that taking just one of these genes (growth hormone) and inserting an extra copy into an animal's DNA is a complex business and can have effects previously unknown. For example, CSIRO research indicates that these transgenic sheep had a higher fecal worm egg count, indicating they may be more susceptible to internal parasites - something previously unsuspected. This image shows the larger transgenic sheep modified with an extra copy of sheep growth hormone gene on left, normal-sized control sheep on right.

Libraries and tags

•  animal husbandry   sheep   transgenic animals   genetics and molecular biology