Content of taurine and other free amino acids in milk of goats bred in Italy

Abstract

Taurine, considered a `conditionally essential amino acid' and the profile of free amino acids in milk from four different goat breeds bred in Italy ( Garganica, Maltese, Saanen and Derivata di Siria) were determined by using a new physico-chemical purification system. The trial involved three different stages of lactation: beginning, middle and final. Taurine was the most representative free amino acid in goat milk, followed by glycine, glutamine and glutamic acid. Taurine was significantly the highest in the Maltese breed milk (90.90 vs. 55.21, 49.59 and 36.80 μmol/100 ml in Garganica, Derivata di Siria and Saanen, respectively). Also, the total amino acid content in the Maltese breed was significantly higher (252.10 μmol/100 ml vs. 200.62 in Derivata di Siria, 200.45 in Garganica and 174.42 in Saanen). As far as the trend during lactation was concerned, the Tau amount was the highest at the final stage, but a significant difference was found only between the second and the final stages. The multivariate analysis of variance showed a highly significant difference ( P=0.0001) for breed factor, lactation stage factor and for their interaction. This investigation showed also that the milk from goats, bred in Italy, and especially from the Mediterranean breeds, had a high content of taurine in all stages of lactation, and new-borns and infants fed goat milk do not need any addition of this amino acid. Further investigations are needed to verify if Maltese milk has higher taurine contents than other breeds.