Prognosing the sex of adults of Amblyomma auricularium through evaluating the biological parameters of engorged nymphs

摘要

Maintaining tick colonies under laboratory condition, as well as carrying out experimental studies on these arthropods may be more successful with better knowledge of some basic biological parameters. In this study, we evaluated how the weight, engorgement period and premolt period of Amblyomma auricularium nymphs (N=600) correlated with the sex of the adults that subsequently emerged. The experiment was carried out in the W.O. Neitz Parasitological Research Station, Ixodology Laboratory of the Department of Animal Parasitology, Federal Rural University of Rio de Janeiro, located in Seropédica, state of Rio de Janeiro. The average weight of the nymphs was 5.1±1.51mg among those that originated males and 8.2±2.5mg among those that originated females. The engorgement period for the nymphs that originated males was 8.3±1.5days while it was longer for the nymphs that originated females, with an average of 8.8±1.8days to complete their diet. The premolt period was shorter for nymphs that originated males (17.2±0.93days) than for nymphs that originated females (17.7±1.00days). Despite an area of overlapping between the weights of engorged nymphs that originated adult males and females, this is the most reliable parameter for predicting the sex of adults of A. auricularium.