Occurrence of Cystoisospora spp. and other intestinal parasites in dogs and cats with diarrhea.

The occurrence of Cystoisospora spp. and other intestinal parasites in young dogs (n. 117) and cats (n. 118) with diarrhea was evaluated. Fecal samples were processed using flotation and sucrose concentration, and fecal and clinical scores were assigned to each animal. Statistical associations between the occurrence of coccidia and/or other intestinal parasites and the severity of clinical signs were evaluated. Seven dogs were infected only with Cystoisospora canis (6.8 %), 3 only with Cystoisospora ohioensis-like (3.4 %) and 1 with both (0.9 %). Forty cats (33.9 %) tested positive for coccidia, i.e. 33 (28 %) only with Cystoisospora felis, 6 (5.1 %) only with Cystoisospora rivolta, and 1 (0.8 %) with both. Other parasites recorded were Giardia spp., Ancylostomatidae, Toxocara spp. and Taeniidae. All dogs with coccidiosis had very soft feces. Watery/hemorrhagic diarrhea was detected in 4/21 (19 %) and 2/5 (40 %) cats infected with C. felis and C. rivolta, respectively. The occurrence of coccidia and Toxocara, and of hookworms and Giardia, was significantly higher (p ≤ 0.05) in cats than in dogs, and vice versa. Other significant associations found in dogs were: reduced activity and positivity to C. canis, presence of very soft feces and positivity to Ancylostomatidae. In cats, the positivity to Ancylostomatidae was significantly correlated with vomiting, dehydration, watery/hemorrhagic diarrhea. This study highlights the frequent occurrence of Cystoisospora spp. in young dogs and cats with diarrhea, with a higher incidence in cats compared to dogs. The clinical score results suggested a more pathogenic role of C. canis and C. rivolta in dogs and cats, respectively.