[The epizootiology and pathogenic significance of infections with Isospora suis in ten piglet production operations in Nordrhein-Westfalen].

From July 1993 to June 1994 2036 fecal samples from 196 litters from 10 pig farms were collected. Three or four piglets from each litter and the respective sows were examined 3 times at 2, 3 and 4 weeks after farrowing. I. suis was detected in all 10 farms. The rate of infection of the litters was 62.2%. 71.6% of all litters with diarrheic problems were I. suis positive. The percentage of I. suis in the feces of piglets was 17.4% at the age of 2 weeks, 41.3% at the age of 3 weeks and 39.1% at the age of 4 weeks. It was also shown that I. suis occurs on any farm with any type of management system and at any time of the year. Fecal samples of sows were always Isospora negative. It is inferred that I. suis is a more important causative agent of porcine neonatal diarrhoea than considered so far. Therefore, further studies on epizootiological and therapeutical aspects and sanitation measures are necessary.