Determinación de los grados de resistencia antihelmíntica que presentan los peque？os strongylus frente a las lactonas macrocíclicas, según el test de análisis del desarrollo de larvas (LDA) en equinos de las sabanas de Casanare

this study was conducted in the grasslands of the department of casanare, seeking to determine the degree of anthelmintic susceptibility or resistance against macrocyclic lactones in small populations of strongylus in this region of the country. samples were taken from four municipalities in the department: aguazul, paz de ariporo, maní and el yopal, between june, 2006 and april, 2007, where ten fresh fecal samples were collected in each municipality, directly from the field and in a completely random way. the samples were processed using the macmaster coprological technique, thus determining the highest count of fecal epg by municipality. l3 larvae were extracted from each of the six samples with the highest count of fecal epg through the coprological and baermann-wetzel tests with which the larvae development analysis (lda) test was run, detecting small strongylus highly susceptible to the action of macrocyclic lactones (ivermectin).