In vivo efficacy of a biotherapic and eugenol formulation against Rhipicephalus microplus.

The control of Rhipicephalus microplus is essential to prevent cattle discomfort and economic losses. However, increased resistance and acaricides inefficiency lead producers to adopt strategies that could result in the accumulation of chemical residues in meat and milk with possibilities of poisoning in animals and people. This scenario demonstrates the necessity of research into the identification of novel, effective and environmentally safe therapeutic options for cattle tick control. The objectives of this study were to develop and assess the efficacy of R. microplus biotherapic and of 5% eugenol for the control of R. microplus in artificially infested calves. Eighteen male 6-month-old Holstein calves were divided into three groups of six animals. In Group 1, the animals did not receive medication (control group); in Group 2, the animals received 1 mL of R. microplus biotherapic at dilution 6CH (centesimal Hahnemannian), orally administered twice daily. And in Group 3, they received a single application of eugenol 5% in the pour-on formulation. The median efficacy for biotherapy and eugenol 5% was respectively 10.13 and 13.97%; however, upon analyzing reproductive efficiency, it is noteworthy that the biotherapic had 45.86% efficiency and was superior to the action of eugenol (12.03%) after 37 days of treatment. The ultrastructural study provided information about the effects of R. microplus biotherapic on the ovaries of engorged females and showed disorganization in the deposition of the oocyte exochorion. The results suggest hatchability inhibition of larvae, interference in R. microplus reproduction and future possibilities for eco-friendly control of R. microplus with biotherapic 6CH.

In vitro acaricidal efficacy of plant extracts from Brazilian flora and isolated substances against Rhipicephalus microplus (Acari: Ixodidae).

The tick Rhipicephalus microplus causes significant losses in livestock cattle and has developed increasing resistance to the primary acaricides that are used to treat these infections. The objective of this study was to identify new biomolecules or isolated substances showing acaricidal activity from plants. Larval packet tests were conducted to evaluate the effects of 11 species of plants and three isolated substances (betulinic acid, eugenol, and nerolidol) on R. microplus. An adult female immersion test was performed with the substance that showed the highest larvicidal activity, which was evaluated for inhibition of reproduction. Tests using Licania tomentosa, Hymenaea stigonocarpa, Hymenaea courbaril, Stryphnodendron obovatum, Jacaranda cuspidifolia, Jacaranda ulei, Struthanthus polyrhizus, Chrysobalanus icaco, Vernonia phosphorea, Duguetia furfuracea, and Simarouba versicolor extracts as well as the isolated substance betulinic acid indicated lower acaricidal effects on R. microplus larvae. The extract displaying the best larvicidal activity was the ethanolic extract from L. tomentosa at a concentration of 60%, resulting in a mortality rate of 40.3%. However, nerolidol and eugenol showed larvicidal activity, which was highest for eugenol. Nerolidol caused a 96.5% mortality rate in the R. microplus larvae at a high concentration of 30%, and eugenol caused 100% mortality at a concentration of 0.3%. In the adult immersion test, 5% eugenol was identified as a good biomolecule for controlling R. microplus, as demonstrated by its high acaricidal activity and inhibition of oviposition.

Enterorrafias em plano aposicional convencionale com adesivo à base de cianoacrilato no cólon descendente de eqüinos / Conventional appositional pattern and cyanoacrylate tissue adhesive in descending colon enterorrhaphy in horses

Em eqüinos, as enterotomias no cólon descendente säo necessárias para remover enterólitos, corpos estranhos e material alimentar compactado que näo podem ser removidos por técnicas conservativas. Este segmento intestinal possui um suprimento sangüíneo pobre, além de predisposiçäo a complicaçöes pós-operatórias relacionadas à contaminaçäo bacteriana. Assim, este estudo foi conduzido com o objetivo de efetuar avaliaçöes clínicas e anatomopatológicas do emprego de adesivo tecidual à base de cianoacrilato no cólon descendente de eqüinos, comparando-o a uma técnica de sutura aposicional convencional. A intervençäo cirúrgica foi realizada em 15 animais posicionados em decúbito lateral direito, através de laparotomia pelo flanco esquerdo, sob anestesia geral inalatória. Após a exteriorizaçäo do cólon descendente, foram realizadas duas enterotomias de cinco centímetros de extensäo cada, distanciadas 20cm uma da outra. Os animais foram aleatoriamente distribuídos em cinco tempos de observaçäo de três animais cada e sacrificados aos três, sete, 14, 35 e 70 dias de pós-operatório. O adesivo butil-2-cianoacrilato e o fio de poliglactina 910 mostraram-se igualmente apropriados para uso em enterorrafias desse órgäo, sendo que o fio de poliglactina 910 provocou inflamaçäo inicial mais intensa que o cianoacrilato e, mais tardiamente, ambos causaram inflamaçäo granulomatosa do tipo corpo estranho observada, primeiramente, junto ao fio de poliglactina 910 (7º dia) e, a partir do 35º dia, ao redor do cianoacrilato