Occurrence of intestinal helminths in two organic pig production systems

Summary

Organically raised pigs are at particular risk of being infected with pasture borne endoparasites, but the housing and management system may nevertheless have a great impact on transmission. In the present study pasture rotation routines on six pig farms representing two different organic management systems were compared; 1) a mobile system, in which the pigs during the summer were living in huts on pastures that were included in a long-term crop rotation scheme, while they during the winter were stabled with access to a concrete yard; 2) a stationary system, in which the pigs all year round were stabled with access to outdoor pastures in the summer time and a concrete yard in the winter. On one farm per system, the faecal excretion of nematode eggs from the pigs were analysed for a period of 3 years. Furthermore, soil samples were collected on a mobile farm to investigate levels of nematode eggs from fields with different pig/fertilizer history. The results showed that the use of a stationary system did not fulfil the actual recommendations for prevention of nematodes. The infection levels of A. suum and Oesophagostomum spp were high in the young pigs in both systems. In contrast, T. suis egg excretion was steadily very low in the mobile system, while the infection level increased during the observation period in the stationary system. The number of eggs in soil from the fields that had been used as pig pastures until November was larger compared to those used only until September, or that was fertilized by manure.