Reproductive abnormality and loss in natural populations of Glossina pallidipes Austen (Diptera: Glossinidae) in Kenya

Abstract

AbstractThe nature, frequency and causes of reproductive loss were investigated in populations of Glossina pallidipes Aust. in western and coastal localities in Kenya. Daily collections from biconical traps in which females were trapped for varying periods up to 30 h were followed by a series of hourly captures which gave less biased data. Ovarian abnormalities and insemination failure were rare, and abortion was the only major source of loss of fecundity. Total reproductive loss was within the range 1·60–1·97% (0·23% ovarian loss plus 1·37% abortions or 1·74% total empty uteri) in western Kenya (Lambwe Valley) and 0·99–1·71% from less comprehensive data at the coast. The incidence of empty uteri was higher in daily than in hourly collections, due mainly to premature parturitions brought about by the stressful effects of prolonged confinement in traps and handling. Abortions were significantly more frequent in females which had ovulated but were not yet parous than in older, parous flies. No relationship between the frequency of abortion and climate, tsetse density or pathogen or parasite infection could be demonstrated.