Changes in free amino acids and peptides in the haemolymph of Glossina austeni during the reproductive cycle.

The animo acids in the deproteinized haemolymph of Glossina austeni females, before and after hydrolysis, have been determined at 12 different times during the 1st 2 pregnancy cycles. Hydrolysis resulted in a large increase in the concentrations of tyrosine, phenylalanine, aspartate and lysine, indicating that these amino acids are present mainly as peptides in the haemolymph. The rate of transfer of the aromatic amino acids to the offspring, based upon the amino acid content of the larval gut, must be exceptionally high and has been estimated to be at least 7.9 microgram/h.