title: [Propensity for feeding on blood under laboratory conditions and chromosomal polymorphism in Anopheles stephensi].
abstract: Propensity to blood feeding under laboratory conditions was studied in females of A. stephensi carriers of different arrangements of a polymorphic paracentric inversion of chromosome 2R (+/+, +/b, b/b). One hour experiments were performed at various hours of the day, in continuous light, with temperature between 26 and 28 degrees C and relative humidity between 65 and 75%, using unfed mosquitoes 4-5 days old and guinea pigs as hosts. The frequency of blood fed females was found to be constantly much lower in the +/+ homokaryotypes, than in the other two karyotypes. Smaller differences in biting activity were observed between the heterokaryotypes and the b/b homokaryotypes, the latter appearing significantly more active at least during the scotophase hours. The evidence of a lower activity of the +/+ homokaryotypes was confirmed when the mosquitoes were stimulated by a human arm. Such marked and constant behavioural difference is tentatively considered as the expression of a diversified response to the environmental conditions whose deterrent effect on biting activity would be more pronounced on the +/+ homokaryotypes than on the carriers of the 2Rb arrangement.
mesh_terms: D000818:Animals; D000852:Anopheles / Q000502:physiology*; D001769:Blood; D002875:Chromosomes; D005247:Feeding Behavior; D005260:Female; D005824:Genetics, Behavioral; D011110:Polymorphism, Genetic
vernacular_title: Propensione al pasto di sangue in condizioni di laboratorio e polimorfismo cromosomico in Anopheles stephensi