Influence of the quality and quantity of blood ingested on reproductive parameters and life-span in Triatoma infestans (Klug).

ABSTRACT

In Triatominae, female fecundity and fertility may be affected by age, adult nutritional status (i.e., blood meal source and amount of blood ingested) and number of matings. Triatoma infestans (Klug) is the main vector of Chagas disease in southern South America and considering that reproductive success is intimately associated with the potential for colonizing or re-colonizing new ecotopes in endemic areas, we studied whether the blood meal source and the amount of blood ingested have influence on reproductive parameters. We constitute two groups couples feeding regularly on guinea pigs and couples feeding regularly on pigeons. We registered quantity of blood ingested, fecundity, fertility, number of matings, days between the first feeding and mating, copula initiation, oviposition initiation and adult life-span. Results showed that females that fed on guinea pigs exhibited high fecundity and fertility, higher number of matings and they needed a lower amount of blood to form an egg. The number of matings and fecundity increased linearly and significantly with the quantity of blood ingested for both meal sources. Results from lineal regression between life-span and fecundity showed a positive and significant relation for both meal sources. The number of matings showed a positive relation with fecundity for both meal sources but significant only for guinea pigs. In T. infestans, the quantity of blood ingested could be a determinant of their reproductive efficiency. This species is mainly adapted to human dwelling and peridomestic structures where there is low host diversity. Considering that this species is in contact with mammals over other food sources, a greater reproductive success may result from an adaptation to this environment.