Gastrointestinal parasites occurrence in dairy cows kept in organic and conventional production system

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The main aim of this study was to determine the effects of pregnancy, calving, lactation, lactation number and seasons on the population of gastrointestinal helminths in dairy cows kept in organic and conventional production system. Between January 2007 and December 2009, coproparasitologic exams were performed using 72 and 43cows kept in conventional and organic system, respectively. The data was submitted to analysis of variance and Student and Tukey test, both at 5% of significance level. There was no difference (p > 0.05) between faecal egg count (FEC) of organic and conventional animals. The mean FEC during calving and lactation was higher (p < 0.05) than during pregnancy. There was no effect of season on the FEC in dairy cows kept in conventional system, while the dairy cows kept in organic system were significantly (p <0 .05) more infected during the rainy season. In both production systems the primiparous animals showed FEC significantly higher (p < 0.05) than pluriparous animals. Dairy cows kept in organic and conventional system were equally vulnerable to the subclinical helminthiasis, and the birth order was a risk factor in both systems.