Revista MVZ Córdoba
Print version ISSN 0122-0268
QUIJADA P, Jessica et al. DISTRIBUTION AND ABUNDANCE OF DIGESTIVE bYLES EGGS IN NATURALLY INFECTED BOVINES. Rev.MVZ Cordoba [online]. 2008, vol.13, n.2, pp. 1280-1287. ISSN 0122-0268.
Objective. To quantify the prevalence and parasitic burdens of byles in naturally infected bovine herds in an important western cattle production area in Falcon state, Venezuela. Materials y methods. Four ranches with the “Carora” breed (result of crossing Holstein, Swiss Brown, Zebu) were sampled over a seven month period. Every month cattle were examined by the McMaster coprological technique. In each ranch, sampling was stratified among four age groups (calves: 0-6 mo; “maute”: 7-12 mo; heifers: 13-24 mo; adults: >25 mo). Results. A total of 1140 samples were collected. Mean prevalence values were 31.06-50.36%. Statistical differences in prevalence values among ranch and age groups were observed. Infections showed an over-dispersed distribution in each herd, as confirmed by very low K coefficients (0.001-0.01). Conclusions. Abundance values (EPG average) were mostly affected by the number of animals with a high parasitic burden rather than high prevalence values at each of the ranches. Most infections were not clinically relevant; animals with high parasite burdens were 1.75-28.56% of the total number of animals evaluated.
Keywords : Prevalence; parasites; parasitic; byles; bovines; Venezuela.