Publications by authors named "L C Perez-Cogollo"

Gastrointestinal nematodes cause serious economic losses in sheep production systems. To determine the prevalence and risk factors associated with these parasites, a study was conducted on 595 sheep in Córdoba, Colombia. Prevalence and parasite burden were determined using the McMaster technique.

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Two bioassays were conducted in parallel to assess the effects of cattle treated with either 1% ivermectin (IVM) or 3.15% IVM (dosed at 0.2 and 0.

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Previous work has documented toxic effects of ivermectin (IVM) on dung beetles from the Old World, but very little is known about this drug's effect on Neotropical dung beetles. Accordingly, we conducted a bioassay with dung spiked with IVM to assess its lethal and sublethal effects on the Neotropical dung beetle Onthophagus landolti Harold. The experimental design consisted of five treated groups G1, G2, G3, G4, and G5 receiving 0.

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Ticks and the diseases they transmit cause great economic losses to livestock in tropical countries. Non-chemical control alternatives include the use of resistant cattle breeds, biological control and vaccines. However, the most widely used method is the application of different chemical classes of acaricides and macrocyclic lactones.

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The objective was to determine the prevalence of semi-intensive Bos indicus and Bos indicus × Bos taurus cattle herds with ivermectin (IVM) resistant nematodes in a sub-humid tropical zone of Mexico using the faecal egg count reduction test (FECRT). Thirty-three herds (28 beef and 5 dual purpose herds) were monitored in a period of 6 months (September 2008 to February, 2009). Only 14 of the 33 herds were included in the trial.

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