Efeito de diferentes teores de umidade relativa sobre fêmeas ingurgitadas, ovos e larvas em jejum de amblyomma cajennense (acari: ixodidae)*

ABSTRACT: SILVA C.L.G. da, E. DAEMON, A.C.G. dos SANTOS & J.L.H. FACCINI. Effects of relative humidities on engorged females, eggs and unfed larvae of Amblyomma cajennense (Acari: Ixodidae). Rev. VQiv. Rural_ Ser. Cienc. Vida, 22 (Supl.):137-142, 2000.- This experiment was conducted aiming to evaluate the effects of different relative humidities on free - living phase of Amblyomma cajennense. A total of 120 females artificially engorged on horses were divided in four groups of 30 females. Each group was kept under controlled humidities of 95, 70, 50 and 30% and 26 ± 2°C. The study showed that the weight of egg mass, periods of preoviposition and incubation , percentage of eclosion, egg production and nutrient indexes under 95% RH were statist i cally different from the remainders RHs (p 0,05) between 95% and 70% RH and shorter under 50% and 30% RHs (p<0,05). There was no eclosion under 50% and 30% RHs, and the percentage of eclosion was only 9% under 70% RH against 81% under 95 % RH. The larva! survivorship under 95% RH was higher than 485 days whereas ali larvae ecloded under 70% RH died in 24 hours. It was suggest that reducing the RH from 95% to 70% or l ower affected the free- Iiving phase of the Iife cycle of A. cajennense from oviposition to larva!survivorship.