Variation in thickness and protein content of the cuticle of the female of Glossina austeni

Abstract The thickness and total protein content of the ventral abdominal cuticle of the female tsetse, Glossina austeni , increase during the early part of each pregnancy cycle, reaching a maximum at approximately 2 days after ovulation. They decrease thereafter, and reach a minimum value just before larviposition. Virgin females do not exhibit a cycle of protein content or thickness in the cuticle. Preliminary data on the incorporation of [ 3 H]tyrosine or [ 3 H]leucine into the water‐soluble proteins of the ventral abdominal cuticle at the time of the second larviposition suggest that there is rapid turnover of protein in the cuticle at this time. These observations are consistent with the net storage of protein in the cuticle during the early part of pregnancy cycle followed by a net depletion of that store as the nutritional demands of the rapidly growing larva in utero exceed the capacity of the ingested blood meals to supply them.