Evaluation of techniques for detection of small trematode eggs in faeces of domestic animals

This study was conducted to evaluate techniques for detection of small trematode eggs in faeces of dogs, cats and pigs. Faecal samples from dogs (n = 80), cats (n = 35) and pigs (n = 114) were examined by Kato-Katz technique (KK), formalin–ether sedimentation technique (FE) and a method of combining: filtration, sedimentation and centrifugation, developed at DBL – Centre for Health Research and Development (former Danish Bilharziasis Laboratory) (DBL). Necropsy was performed on 38 dogs, 25 cats and 16 pigs and was considered as a gold standard method for evaluation of the techniques. The results showed 100% specificity for the three techniques. Lower sensitivity was seen for the KK-technique in dog samples in comparison to that for DBL- and FE-technique. The sensitivity of the three techniques was similar in cats and pigs. Based on these findings and practical issues, DBL-technique was chosen as most suitable because the eggs were easily detected and quantified. No toxic chemicals or special equipment were required in comparison with FE-technique that needs ether solution and thus fume cupboards which are often unavailable in local veterinary centres in Vietnam and other developing countries.