Ticks (Acari: Ixodidae) associated with wild animals in the Pantanal region of Brazil.

This paper describes the identification of ticks from wild animals of the Pantanal region in Brazil as part of a comprehensive study about established and emerging tick-host relationships and related pathological aspects. Eighty-one animals were captured (representing 13 species, six orders), and ticks were found on 63 (78%). Tick species identified included Boophilus microplus (Canestrini), Amblyomma cajennense (F.), Amblyomma parvum Aragão, Amblyomma pseudoconcolor Aragão, Amblyomma scalpturatum Neumann, Amblyomma nodosum Neumann, Amblyomma ovale Koch, and Amblyomma tigrinum Koch. Dragging from grasslands yielded negative results compared with the high concentration of ticks that were collected from leaves in the forests.

Daily mean number of eggs laid by the southern cattle tick (Acari: Ixodidae) compared with mean egg mass weight.

Among several methods used to estimate the efficacy of an acaricide is the Drummond adult test, based on formulas which permit the assessment of the reproductive capacity of treated female ticks in comparison with controls. A constant value of 20,000 is normally used in these formulas, because this figure approximates the number of larvae that will hatch from 1 g of eggs. In laboratory studies conducted on large numbers of ticks, egg counting is a time-consuming and fastidious operation. Therefore, in quantitative studies, sampling techniques are more convenient. The use of the weight of egg masses laid by ixodids is adequate because eggs congregate in clusters. Experimental results have demonstrated that the analysis of the mean daily weight of egg aliquots in comparison with actual counts, from the 1st to the 20th d of oviposition, did not permit rejection of the hypothesis that 20,000 would be a representative number of eggs contained in 1 g. When aliquots were weighed only on the 20th or the 30th d of the oviposition-incubation period, and the results were analyzed in comparison with egg counts, the value of 20,000 no longer was reliable to express the number of Boophilus microplus (Canestrini) eggs contained in 1 g.

Efficacy of some inseticides for control of the horn fly

A eficácia de formulaçöes pour-on de alfa-cipermetrina e a de formulaçöes para aplicaçäo por pulverizaçäo, tanto de alfa-cipermetrina como de cipermetrina associada ao clorfenvinfos, assim como a de clorfenvinfos utilizada isoladamente, foi avaliada no controle da mosca-dos-chifres em gado de corte mantido em sistema de pastejo. A populaçäo de moscas foi monitorizada durante 42 após o tratamento. O estudo indicou que todos os tratamentos utilizados proporcionaram pelo menos 90 por cento da reduçäo da populaçäo de mosca-dos-chifres durante as seis semanas de conduçäo do experimento e que, no momento, deve ser considerada a conveniência da utilizaçäo dessas formulaçöes para o controle da Haematobia irritans no Brasil

Efficacy of pyrantel pamoate either alone or combined with trichlorfon for control of cyathostomes of horses

Através de estudo comparativo, objetivou-se avaliar a eficiência anti-helmíntica de pamoato de pirantel, isolado ou associado ao triclorfon, no controle de estrongilídeos de equinos da raça Puro Sangue Inglês. As coproculturas realizadas antes e após os tratamentos levaram consistentemente ao encontro de populaçöes puras de ciatostomíneos com oito células intestinais. As reduçöes de ovos por grama de fezes foram avaliadas do 7§ ao 45§ dias pós-tratamento. Comparando os valores médios de OPG dos equinos tratados com pamoato de pirantel (13,2 mg/kg) associado ao triclorfon (30 mg/kg) e com pamoato de pirantel isolado (13,2 mg/kg), observou-se diferença näo significante (P<0,05) ao longo do experimento, verificando-se, 7 dias após o tratamento, reduçöes médias de OPG de quase 100 por cento e, do 7§ ao 20§ dias, reduçöes ainda superiores a 90 por cento. Os resultados indicam que os dois produtos säo eficazes na reduçäo de ovos por grama de fezes de ciatostomíneos de equinos mantidos sob condiçöes a campo