• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Master's Dissertation
DOI
Document
Author
Full name
Rafael Lanzelloti Fonseca
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2019
Supervisor
Committee
Gorniak, Silvana Lima (President)
Brossi, Camila
Camargo, Jaci Clea de Carvalho
Title in Portuguese
Ivermectina: estudo farmacocinético em bovinos de corte. Comparação entre raças (zebuína, europeia e seus cruzamentos) gêneros e concentração do medicamento
Keywords in Portuguese
Bos indicus
Bos taurus
Farmacocinética
Ivermectina
Meio-sangue Angus-Nelore
Abstract in Portuguese
A ivermectina foi o primeiro antiparasitário do grupo das lactonas macrocíclicas a ser comercializado, sendo introduzido no mercado, inclusive no Brasil, em 1983. Embora tenham sido desenvolvidos outros tantos antiparasitários pertencentes ao grupo das lactonas macrocíclicas, a ivermectina (IVM) é ainda o mais amplamente empregado antiparasitário na bovinocultura no nosso país. A farmacocinética da ivermectina é caracterizada, em termos gerais, por baixa absorção quando administrada por via subcutânea, largo volume de distribuição, muito pequena biotransformação e excreção lenta. A cinética está diretamente ligada a vários fatores, mas principalmente à via de administração, espécie animal e formulação. O presente estudo foi dividido em três partes, sendo objetivo verificar se há diferenças na farmacocinética da IVM, considerando-se a comparação entre os cruzamentos (europeu, zebuíno e meio- sangue), os gêneros, bem como as diferentes concentrações do antiparasitário (1% e 3,15%). Na primeira parte, foram comparados os perfis farmacocinéticos do Angus, Tabapuã e meio sangue Angus-Nelore. Os resultados mostraram grandes diferenças, tanto nos níveis plasmáticos de 22,23 Dihidroavermectina-B1a, bem como foram detectados valores significantemente maiores no Cmax, ASC e t1/2β nos animais Tabapuã, quando comparado àqueles bovinos de origem europeia e meio-sangue. Na outra etapa, na comparação entre os gêneros e machos castrados, verificou-se que não houve nenhuma alteração, em todos os parâmetros farmacocinéticos avaliados. O estudo, no qual objetivou-se comparar a farmacocinética da ivermectina entre as duas concentrações: 1% e 3,15%, mostrou, como o esperado, várias diferenças no perfil farmacocinético do antiparasitário entre os dois grupos. Assim, inicialmente os níveis de plasmáticos de 22,23 Dihidroavermectina-B1a foram superiores naqueles animais tratados com IVM 1%; no entanto, a partir da 3a semana após a administração do medicamento, esses valores foram significantemente superiores nos bovinos tratados com a maior concentração da avermectina. Em relação aos parâmetros farmacocinéticos, conforme o esperado, houve maiores valores de Tmax, ASC e t1/2β naqueles animais que receberam IVM 3,15%. Entretanto, pelos dados farmacocinéticos, aqui obtidos, pode-se levantar a hipótese de que os períodos de retirada propostos pelo fabricante para IVM 3,15% é seguro, mesmo para animais de origem zebuína.
Title in English
Ivermectin: pharmacokinetic study in beef cattle. Comparison between breeds (zebu, European and their crosses) genres and drug concentration.
Keywords in English
Bos indicus
Bos Taurus
Cross breed AngusNelore
Ivermectin
Pharmacokinetics
Abstract in English
Ivermectin (IVM) was the first antiparasitic of the macrocyclic lactone group to be marketed and was marketed, including in Brazil, in 1981. Although many antiparasitics drugs have been developed in the macrocyclic lactone group, ivermectin is still the most widely used antiparasitic in Brazil. The pharmacokinetics of IVM are generally characterized by low absorption when administered subcutaneously, large volume of distribution, very small biotransformation and slow excretion. The kinetics is directly linked to several factors, but mainly route of administration, animal species and formulation. The present study was divided in three parts, with the objective to verify if there are differences in the pharmacokinetics of the IVM, considering the comparison between the crosses (european, zebu and half-blood), the genera, as well as the different concentrations of antiparasitic (1 % and 3.15%). In the first part, the pharmacokinetic profiles of Angus, Tabapuã and the cross breed Angus-Nelore were compared. The results showed large differences in plasma levels of 22,23 Dihydroavermectin-B1a, as well as significantly higher values in Cmax, ASC and t1 / 2β in the Tabapuã animals when compared to those of european and half-blood cattle. In the other step, in the comparison between genders and castrated males, it was verified that there was no change in all pharmacokinetic parameters evaluated. The study, which aimed to compare the pharmacokinetics of IVM between the two concentrations: 1% and 3.15%, showed, as expected, several differences in the pharmacokinetic profile of the antiparasitic between the two groups. Thus, initially plasma levels of 22.23 Dihydroavermectin-B1a were higher in those animals treated with ivermectin 1%; however, from the third week after administration of the drug, these values were significantly higher in cattle treated with the highest concentration of the avermectin. Regarding the pharmacokinetic parameters, as expected, there were higher values of Tmax, ASC and t1 / 2β in those animals that received ivermectin 3.15%. However, from the pharmacokinetic data it can be hypothesized that the withdrawal periods proposed by the manufacturer for IVM 3.15% would be safe, even for animals of zebu origin.
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
Publishing Date
2019-10-21
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
CeTI-SC/STI
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2021. All rights reserved.