Abstract:
A study was undertaken on the prevalence of cutaneous
myiasis in domestic animals and its control using
bio-pesticides and gamma irradiation.
The prevalence of cutaneous myiasis in domestic animals
was found to be 205 (2.08 per cent) among .the 9861 animals
screened. The peak of infestation was noted in the month of
January. In host-wise and parasite-wise the highest incidence
was noted in cattle (63.41 per cent) and the majority of
infestation was produced by Chrysomya bezziana larvae (90.73
per cent). Methoprene at 1 to 50 ppm concentration caused only
moderate mortality on larvae but significantly increased the
mortality rate on eggs, prolonged the larval phase, increased
the formation of larval pupal intermediaries and adult
deformities and reduced the adult emergence. Diflubenzuron at
0.5 to 5 ppm caused 55 to 100 per cent larvicidal effect due
to lowered chitin content of 18.42 to 52.11 per cent in larval
cuticle. Bacillus thuringiensis var israelensis produced only
moderate larval mortality at 160 to 800 ppm in myiasis
producing flies. Azadirachtin at 10.5 to 15 ppm produced 100
per cent mortality in eggs and larvae. Significant
antifeedant, ovipositional deterrent and repellant effects
were also produced by Azadirachtin. Among the extracts of
Acarus calamus, studied, petroleum ether extract at 2.5
per cent concentration gave 82.5 to 100 per cent mortality of
the larvae. Moderate antifeedant, ovipositional deterrent and
repellant effects were also noticed. The petroleum ether
extract produced 100 per cent sterility at 0.1 to 1 per cent
concentration by preventing the development of ovarian
follicles. Three day old pupae of myiasis producing flies
exposed to r-rays gave excellent sterility effect at 2000 to
4000 rads radiation exposure without any other deleterious
effect in the flies. Diflubenzuron at 5 ppm concentration
showed the highest larvicidal effect (88.5 per cent) in
natural cases of cutaneous myiasis.
