Influence of the salmon mutant of Glossina morsitans morsitans on the susceptibility to infection with Trypanosoma congolense.

Four phenotypes of a sex-linked, maternally influenced semi-lethal eye color mutant of Glossina morsitans morsitans Westwood were fed on Trypanosoma congolense Broden infected guinea pigs. Infection rates were evaluated 25 days later by means of dissection. Procyclic as well as mature infections were significantly more common among females with salmon-colored eyes (sal/sal) than among heterozygous (+/sal, phenotypically wild-type) females. A tendency was found for more mature infections among sal/Y males than among wild-type males. Similarly, females tended to be more infected than males with both procyclic and mature infections. These results indicate that the genotype of the fly, exemplified by the allele salmon, might influence the development of T. congolense in G.m. morsitans. A possible explanation for this phenomenon is discussed.