Balantidium, Cryptosporidium and Giardia species infections in indoor and outdoor pig production units in Croatia

IN order to maximise profit, outdoor production has been implemented on many pig production units in Croatia (Akos and Bilkei 2004). The low animal density on outdoor units positively influences the growth performance of young pigs in units suffering problems with respiratory diseases (Docic and Bilkei 2001) or Lawsonia intracellularis (Bona and Bilkei 2003). However, studies from Germany and Hungary have shown that outdoor production exerts a negative effect on the performance of weaned piglets (Bolcskei and others 1996), growing-finishing pigs (Clark and Bilkei 2003) and breeding sows (Karg and Bilkei 2002) suffering infections with pathogenic Escherichia coli and Ascaris suum. Giardia duodenalis, Balantidium coli and Cryptosporidium species are foodborne, waterborne or environmental pathogens. From the point of view of the practising veterinarian, all three pathogens represent a neglected field in outdoor pig production. This short communication describes a study to evaluate the performance of Giardia-, Balantidiumand Cryptosporidium-infected pigs in outdoor and indoor systems, raised under identical nutritional management programmes and in the same geographical area. Faecal samples were collected from 17 outdoor and 21 indoor pig production units in Croatia (female line F1 Landrace x Large White, mated to Duroc or Landrace boars) in July and August 2004. The units suffered from subclinical enzootic pneumonia causing respiratory health problems, subclinical swine dysentery and proliferative enteropathy causing production losses. Pretrial serological testing, by using an indirect ELISA, had shown that all units were positive for antibodies to Mycoplasma hyopneumoniae; immunofluorescent antibody tests showed positive titres to Brachyspira hyodysenteriae and L intracellularis in all the units. The samples were collected from the rectum of five growing-finishing pigs on each unit. All the samples were analysed for the presence of Giardia, Balantidium and Cryptosporidium species antigens by ELISA, using the ProSpec T Giardia, Balantidium and Cryptosporidium Microplate Assays (Alexon-Trend). The average daily gain and the mortality of the pigs were evaluated and statistically compared by using