In vitrorearingOestrus caucasicusthird-instar larvae and pupae (Diptera: Oestridae) from naturally-infested Iberian ibex,Capra pyrenaica(Artiodactyla: Bovidae)

Abstract

Summary :Third-instar Oestrus caucasicus larvae (n = 236) obtained from Iberian ibex, Capra pyrenaica, were reared in a laboratory to obtain adult flies. They were maintained at a temperature of 21.9 ± 2.7°C and a relative humidity of 38.9 ± 8.0 %. In all, 78 imagos emerged (33.1 %), with a sex-ratio at emergence not differing significantly from 1:1; 25 larvae did not complete pupariation. A total of 14 adult flies (17.9 % of the adults obtained) showed malformations, mainly in their wings. The pupariation period lasted around 30 hours and the pupal stage lasted on average 29.8 ± 6.8 days. The success of pupation in both sexes was mainly determined by the weight of the larvae. Sexual dimorphism, with higher weights in females, was evident in third-instar larvae, pupae and adults. The mean longevity of adult flies was 224.8 ± 91.4 hours and males generally survived for longer than the females. Résumé : CULTURE IN VITRO DE LARVES ET NYMPHES D'OESTRUS

A system dynamics model of the population dynamics ofOestrussp. (Diptera: Oestridae) infesting Iberian ibex,Capra pyrenaica

“…For this reason, hereafter, we call it Oestrus sp. Regarding morphological and biological features, this latter parasite species is very similar to O. ovis (Grunin 1957;Zumpt 1965;Colwell 2001;Guitton et al 2001;Pérez et al 2006).…”

“…Values assigned to the relationships between levels and auxiliary variables of the model were obtained from the literature. Adult life expectancy was considered as the mean obtained for males and females: 0.31 ± 0.13 months (Pérez et al 2006). The biotic potential for Oestrus sp.…”

“…In addition, in vitro culture experiments showed that Oestrus sp. post-feeding third-instar larvae have a mortality rate of 10.6% and that they take 1.28 days ("Time L3 to Pupae") on average to pupate, the pupal stage then lasting for 30 days (Pérez et al 2006); all of these values were included in the model.…”

“…The emergence rate of adult flies reaches 43.6% (assuming a mortality rate of 56.4% during the pupal phase) with a sex ratio not differing significantly from 1:1 (Pérez et al 2006). However, we assumed that 17.9% of adult flies emerged with vestigial wings and would probably not reproduce (Pérez et al 2006). Because we have no information about the natural mortality of adults (e.g.…”