M Abolhasani , M Shaeghi , H Ladonii ,
Volume 1, Issue 4 (8 2003)
Abstract
In this study we employed two methods for gauging the sensitivity of B. germanica strains to organophosphorus insecticides: an in-vivo bioassay that used linear regression analysis (with mortality on a probit scale and logarithm of concentration) and an in-vitro enzyme assay.
In the bioassay method, B. germanica nymphs of stage 1 (2-3 days old) were exposed to patches of paper impregnated with 2% diazinon and propoxur. Compared to the sensitive (reference) strains, all but one of the tested strains showed resistance to diazinonzinon with resistance ratios of 0.97 to 1.67. As for propoxur, all strains were sensitive with the exception of one subject that showed a resistance ratio of 1.6. The enzyme assays used common esterase and acetylcholine esterase methods. Comparison of in-vivo and in-vitro tests on stage 1 nymphs of B. germanica shows that both methods are reasonably sensitive in measuring resistance/sensitivity ratios. In addition, the bioassay modality makes it possible to gauge the degree of insecticide sensitivity while the in-vitro method can only determine quantitative or qualitative changes in enzymes effected by carbamates and organophosphates. This study is the first of its kind, conducted by the school of Public Health in Tehran University of Medical Sciences.
M Shayeghi , N Piazak , F Yazdi , M Abolhasani ,
Volume 3, Issue 3 (3 2005)
Abstract
This survey was done to investigate the geographical distribution of ticks (Hard and Soft) in the towns of Amol, Babol and Noor in Mazandaran province, north of Iran. The study, conducted from January 2000 to October 2001, covered mostly rural districts and a total of 15 operational fields.
Ticks were collected from domestic fowl nests, stables (animal shelters, floors and other places), animal bodies and rodent holes. A total number of 3897 ticks from two families (Argasidae and Ixodidae) were collected. Ticks from the Argasidae Family totaled 2049 and belonged to 2 genera: Argas and Ornithodorus). The proportions of different species were as follows: Argas persicus 35.95%, A. reflexus 0.97% and O.lahorensis 15.65%. Hard ticks collected in the area belonged to 6 genera and included 8 species: Boophilus (B. annulatus 8.34%) Haemaphysalis (Hae. Sulcata 5%), Hyaloma (Hy. marginatum 1.66%), Dermacentor genus and Hyschulza (0.75%).
Hy. anatolicum (1.33%) De. marginatus (1.72%), the genus Rhipicephalus (Rh. Sanginues 1.18%) were collected from animal bodies (cow, sheep, goat) and animal shelters.
