Twelve sows were used to examine the effects of feeding L-carnitine from artificial insemination to mid-gestation on maternal circulating IGF-I and carnitine concentrations and fetal growth. Supplementing L-carnitine did not influence the serum concentration of IGF-I. However, sows that were fed carnitine had increased circulating plasma free carnitine. Litters
from sows fed L-carnitine were heavier and
had more fetuses. The increase in litter fetus number was not detrimental to other growth traits such as individual fetal weight or crown to rump length. Our study suggests that feeding L-carnitine to gestating sows is beneficial for fetal growth and development.