Parasitismo por larvas de Dermatobia hominis (Linnaeus, Jr. 1781), em bovinos no município de Lorena, Estado de São Paulo

Abstract

Between January, I983 and December, 1984 studies were performed about the parasitism of D. hominis, taking account of the side of the body, age, degree of crossbreeding, side of the body, coat color and monthly variation of the number of larvae in 48 tracer animals, and the capture of vectors of eggs of D. hominis, at São João farm, in the Lorena municipality area, São Paulo State, Brazil. Two trace animals were used monthly, the data were coIlected and statistically analysed. There was no difference among the side of the body, parasitism being identical in both. The degree of crossbreeding did not influenced the infestation, and both European and Zebu cattle were susceptible. The influence of the age of the animals was not important too. The body of the animals was divided in five areas, wich were: area I, head and neck; area II, shoulder, foreleg xix and breast; area III, back and croup; area IV, sides and lower belly and area V, quarters, hind leg and tail. Area IV showed more parasitism than the others, foIIowed by area II (35,82 and 23,32% respective|y). Coat color was also important, and the animals were classified in six groups, the ones with black coat showing more D. hominis larvae, foIlowed by brown/gray and red coats. The highest infestations were seen in January and June to October 1983, and January, October and December 1984. And the lowest occurred in March, April and December 1983, and in February, March, July and November 1984. During four months two methods of the capture of vectors, W.O.T. (Wind Orientated Trap) and entomological net. Six insects were captured with entomological net carrying D. hominis eggs. From those, five were Sarcopromusca pruna and the other were Musca domestica. The range of eggs laid in the vectors was 15 to 78, averaging 31,16 eggs