Amino acid profile in natural prey of sole-Solea solea

The amino acid profile of the dominant prey items of the sole natural diet was analysed; differences in the quantity and proportions of non-essential and essential amino acids between the sexes were determined. The highest level of total amino acid was found in Upogebia from F. Callianassidae. The prey items with a higher proportion of essential amino acids are Callianassidae, Glyceridae and Apseudidae. As a higher quantity of prey was found in the female stomach contents, a higher level of amino acids was found in the female diet. Differences between the sexes in essential amino acid proportions in sole spring diet have not been found. In both sexes, phenylalanine, histidine and lysine are the most abundant essential amino acids and valine the least abundant. © 1994.