ABSTRACT
Much attention has been given to the development of botanical insecticides to provide effective natural control of cattle ectoparasites without harming animals, consumers, and environment. This study evaluated the efficacy of a commercial neem cake in controlling Haematobia irritans infestation on cattle. The study was conducted at the Embrapa Southeast Cattle Research Center (CPPSE), in São Carlos, SP, Brazil, from April to July 2008. The neem cake mixed in mineral salt in a 2% concentration was provided to 20 Nelore cows during nine weeks and had its efficacy evaluated by comparison of the infestation level against a control group. Fly infestations were recorded weekly by digital photographs of each animal from both groups and the number of flies was later counted in a computer-assisted image analyzer. Quantification of neem cake components by high-performance liquid chromatography revealed the presence of azadirachtin (421 mg.kg potention 1) and 3-tigloyl-azadirachtol (151 mg.kg potention 1) in the tested neem cake. Addition of the 2% neem cake reduced mineral salt intake in about 22%. The 2% neem cake treatment failed to reduce horn fly infestations on cattle during the 9-week study period.
Muita atenção tem sido dada ao desenvolvimento de inseticidas vegetais buscando-se um efetivo controle de ectoparasitas de bovinos, sem prejudicar animais, consumidores e meio ambiente. Este estudo, realizado de abril a julho de 2008, na Embrapa Pecuária Sudeste, em São Carlos, SP, Brasil, avaliou a eficácia de uma torta comercial de nim (Azadirachta indica) no controle da mosca-dos-chifres (Haematobia irritans) em bovinos. A torta de nim, misturada ao sal mineral na concentração de 2%, foi fornecida a 20 vacas Nelore, durante nove semanas, e sua eficácia foi monitorada através de contagens semanais nos grupos tratado e controle. Infestações individuais foram registradas por meio de fotos digitais em todos os animais de ambos os grupos, e o número de moscas foi, posteriormente, quantificado com o auxílio de um sistema de análise de imagem computadorizado. A quantificação dos componentes da torta de nim, por cromatografia líquida, revelou a presença de azadiractina (421 mg.kg elevado a 1) e 3-tigloyl-azadirachtol (151 mg.kg elevado a 1). A adição da torta de nim a 2% reduziu o consumo de sal mineral em cerca de 22%. O tratamento com torta de nim a 2% não reduziu as infestações por mosca-dos-chifres em bovinos durante as nove semanas do estudo.
Subject(s)
Animals , Cattle , Azadirachta/adverse effects , Cattle/parasitology , Ectoparasitic Infestations/prevention & control , MuscidaeABSTRACT
Gastrointestinal nematode infections were evaluated in Santa Inês crossbreed sheep (Santa Inês predominance) in a rotational grazing system and in lambs kept indoors, born from the breeding of these females with purebred Santa Ines, Dorper and Suffolk males. Fecal egg counts (FEC), fecal cultures, packed cell volume (PCV) and weights were evaluated during two years. Climate data were registered. Only animals that presented FEC higher than 4,000 and/or PCV lower than 21% were drenched with anthelmintic treatment and this rational use controlled the infection in the flock satisfactorily. An adequate diet during the rainy season and supplementation in dry period were important to increase relative resistance and resilience to parasites, since Haemonchus contortus was detected year-round in this region. The peripartum physiological condition influenced gastrointestinal nematode infections significantly. Crossbred (1/2) Santa Inês + (1/2) Dorper lambs did not show a significant difference in FEC when compared with other breeds, but they had greater live weight and reached slaughter weight earlier.
