A critical review is given about the use of carnitine supplementation
in animals for zootechnical purpose. The main function of carnitine is
the transport of long chain fatty acids through the inner mitochondri
al membrane for energy production. Only the L-isomere is endogenously
synthetised in the body of vertebrates. The D-form can inhibit L-carni
tine and should not be administered. The major sources of carnitine ar
e of animal origin, like meat. The use of carnitine has been proposed
for a range of applications in very different domains like muscle stre
ngth, production and reproduction and diseases of heart, liver, kidney
and other organs. Even neurological problems are claimed to be effect
ed by carnitine. A synthesis of the biochemical and physiological aspe
cts of L-carnitine is made. New applications of L-carnitine supplement
ation in animals have been suggested.