The rapid development of modem biotechnology has introduced a new dime
nsion to veterinary medicine and animal breeding. Genome analysis of i
mportant breeding species will ultimately allow to detect and conseque
ntely to eliminate any possible genetic disorder. Moreover, infectious
diseases may also be detected easier and more reliable. The productio
n of transgenic lifestock opens the possibility to generate animals wi
th improved health and productivity without time consumig breeding pro
grammes. In the following review I will focus on the description of re
cent developments in the application of molecularbiological techniques
in veterinary medicine and animal production. Special emphasis will b
e given to the physiological consequences of transgene expression rath
er than the techniques for the production of transgenic animals.