Parasitological research on fattening pigs raised under organic production system: correlation between animal density and mean egg/oocyst emission

摘要

Purpose of the research were to study the importance of coccidiosis and helminthiasis in organic fattening rearing, and to evaluate correlation between parasitic intensity/abundance and animal density. Materials and methods: from December 2003 to March 2004 we monitored two groups of organic pigs, located in Ceregnano (Rovigo province, Veneto region), reared in continuous pasture (1200 m~2) and aged from 4 to 11 months. Group 1 and 2, respectively of 7 and 26 animals, were monitored fortnightly, examining for each group 7 specimens not identified. On all specimens coprological investigations were carried out, both qualitative by flotation in heavy solution (sg 1.3), and quantitative by Mc Master technique. Pooled positive faeces were used for sporulatation of the oocysts, using Pellerdy's key for identification (Pellerdy LP, 1974, Coccidia and Coccidiosis, Verlag Paul Parey, Berlin, Germany). Differences in mean EPG/OPG emission between the 2 groups in general and for each sampling were evaluated by the non-parametric Mann-Whitney U test.