Eficácia anti-helmíntica comparativa entre diferentes princípios ativos em ovinos jovens

Abstract

The objective of the present study was to verify the efficacy of different anthelmintics in young sheep and the variation between males and females. The work was carried out between March and April 2015 in private property in the municipality of Dom Pedrito - RS. The evaluations were carried out on 180 lambs (90 males and 90 females) crossed Corriedale x Ile de France with mean age of 10 ± 2 months live weight (LW) of 26.00 ± 2.0 kg kept in intermittent grazing with fixed stocking In 20 hectares (ha) of native field. The animals were separated into three groups which received different active principles (Closantel 10% via oral; 30% oral Diophenol and 34% Nitroxinil via injectable). Each group consisted of 60 individuals 30 males and 30 females. The faeces were collected before the application of the active principle (day zero) and after 10 days for the quantification of eggs per gram of faeces (OPG). Also the cultivation of larvae (coproculture) was carried out. The efficacy test was checked according to the following formula Efficacy (E%) = [(OPG control day0 – OPG treatment day10) /OPG day0 ] x 100. All OPG averages were found to be above the maximum dosage limit (OPG> 500). The anthelmintic efficacy in the herd for Closantel dysophenol and Nitroxinil was 64% -7% 60% respectively and efficacy less than 90% is sufficient to presume the resistance of helminths to these drugs. When efficacy was observed between the sexes it was found that all drugs were considered ineffective. However it is worth noting that the efficacy of the active ingredient Nitroxinil was 72% in lambs and 33% in lambs. The population of nematodes identified in the coproculture of the herd referring to day 0 was Haemonchus spp. (45%) followed by Trichostrongylus spp. (53%) and with fewer occurrences Bonostomum spp. (2%). When identification was performed after treatments (day 10) the presence of Haemonchus spp. (43%) Trichostrongylus spp. (56%) and Bonostomum spp. (1%). Efficacy and coproculture tests should be carried out periodically in the herd in order to guide the selection of the most appropriate anthelmintic in the control of verminosis. Comprovou-se que na propriedade há resistência anti-helmíntica aos princípios ativos utilizados. Embora, fosse verificada maior eficácia nas cordeiras fêmeas tratadas com Nitroxinil em comparação aos machos do mesmo grupo, ambos foram considerados ineficazes no combate à parasitose.

Efficacy of antiparasitic drugs in control of gastrointestinal helminthiasis in naturally colored and white lambs from southern Brazil

“…According to the guidelines provided by MAPA (BRASIL, 1997) and based on our findings, this drug would be considered insufficiently active in the two parasitized phenotypic groups studied and therefore should not be used in the treatment of gastrointestinal nematode infections in sheep. Disophenol resistance in lambs from the State of Rio Grande do Sul, southern Brazil, was recently documented by Silva et al (2017). Similar findings were reported by Cezar et al (2010) even when the drug was used at higher concentrations (20% disophenol).…”

“…Gastrointestinal (GI) parasitic infections are one of the major health problems affecting sheep herds worldwide (Taylor et al, 2007;Molento et al, 2013;Vieira et al, 2014) and can reduce the productivity of herds and result in high mortality rates if treatment, prevention and control measures are not readily implemented (Vieira et al, 2014;Benavides et al, 2015;Silva et al, 2017). Young animals are particularly susceptible to GI nematode infections as they are unable to mount an effective immune response against these parasites (Schallig, 2000).…”

“…However, prolonged use of antihelminthics results in antiparasitic drug resistance. There are reports of resistance of parasites to the main antiparasitic drugs available in the market for the treatment of gastrointestinal helminthiases of farm animals (Taylor et al, 2007;Cezar et al, 2010;Nova et al, 2014;Vieira et al, 2014;Dias et al, 2015;Costa et al, 2017;Silva et al, 2017).…”

A Produção De Alimentos Orgânicos Numa Perspectiva Bioeconomica

“…As enfermidades podem influenciar no desempenho dos animais, ocasionando anemia, perda de peso e diminuição do potencial reprodutivo, além de, em casos extremos, levar a óbito (AMARANTE, 2009;LOPES et al, 2013;SILVA et al, 2017).…”

Dieta proteica e transcriptômica de tecidos associados à resposta imune de ovinos infectados por Haemonchus contortus

“…A seleção de populações de endoparasitos resistentes aos antiparasitários é um problema global e há relatos de resistência anti-helmíntica a praticamente todos os grupos químicos de anti-helmínticos (Kaplan;Vidyashankar, 2012), como ocorre frequentemente nas regiões tropicais e subtropicais da América Latina (Thomaz-Soccol, 2004;Silva et al, 2017).…”