INVESTIGADORES
ALVAREZ Luis Ignacio
artículos
Título:
The route of administration drastically affects ivermectin activity against small strongyles in horses
Autor/es:
CARLOS SAUMELL, ADRIÁN LIFSCHITZ, RENATO BARONI, LUIS FUSÉ, MARIANA BISTOLETTI , FEDERICA SAGÜES, SANTIAGO BRUNO, GUSTAVO ALVAREZ, CARLOS LANUSSE, LUIS ALVAREZ
Revista:
VETERINARY PARASITOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2017 vol. 236 p. 62 - 67
ISSN:
0304-4017
Resumen:
The goal of the current study was to evaluate the comparative efficacy of ivermectin (IVM) againstsmall strongyles (cyathostomins) following its oral and intramuscular (IM) administration, in naturallyparasitized horses. The parasitological data were complemented with the assessment of the plasma dispositionkinetics of IVM. The trial included two different experiments. In experiment I, 40 horses naturallyinfected with small strongyles were randomly allocated into four experimental groups (n = 10) and treatedwith IVM (0.2 mg/kg) as follows: IVM oral paste, animals were orally treated with Eqvalan® (IVM 1.87%paste, as the reference formulation) by the oral route; IVM oral solution, animals were orally treated withRemonta® (IVM 2% solution, as a test formulation); IVM IM solution, animals were IM treated with thetest product (Remonta® IVM 2% solution); and control, animals were kept without treatment as untreatedcontrols. In experiment II, 24 horses naturally parasitized with small strongyles were randomly allocatedinto the same four experimental groups (n = 6) described for experiment I. Faecal samples were individuallycollected directly from the rectum of each horse prior (day−1) and at 7 and 15 (ExperimentI) or 7, 15 and 21 (Experiment II) days after-treatment, to assess the eggs per gram (epg) counts andestimate the efficacy of the treatments. Additionally, the comparative plasma disposition kinetics of IVMin treated animals was assessed in experiment II. In both experiments, an excellent (100%) IVM efficacywas observed after its oral administration (test and reference formulations). However, the IM administrationof IVM resulted in a low efficacy (36?64%). Similar IVM plasma concentration was observed afterits oral administration as a paste or as a solution. The higher IVM plasma profiles observed after the IMadministration accounted for an enhanced systemic availability. The improved IVM efficacy observedagainst adult cyathostomins after its oral administration can be explained by an enhanced drug exposureof the worms located at the lumen of the large intestine. These findings may have a direct impact on thepractical use of macrocyclic lactones in horses.