The present study aimed to analyze the occurrence of infection by Cryptosporidium spp. in mares and their respective foals. This study was carried out in 11 farms located in the municipalities of Araçatuba, Birigui, Guararapes and Santo Antônio do Aracangua, in the northwest region of the State of Sao Paulo, from November 2010 to March 2011. A total of 98 mares and 98 foals of several breeds were analyzed; among foals, 59 were males and 39 females, aged from three to 330 days. Feces were collected directly from the rectal ampulla, purified and processed according to modified Kinyoun stain. Occurrence of Cryptosporidium spp. was 21.4% (21/98) for foals and 18.4% (18/98) for mares. Occurrence of Cryptosporidium spp. had significant association with breeds and age of animals. Results obtained led to the conclusion that foals older than two months and Mangalarga animals are less susceptible to the occurrence of Cryptosporidium spp.

Despite the existence of therapeutic and prophylactic measures, gastrointestinal parasites are common in pets. Due to the zoonotic potential of some species, parasitic protozoa and helminths are of great importance to public health. In this study, we investigated the occurrence of the main gastrointestinal parasites in domestic dog puppies in the city of Araçatuba, São Paulo, Brazil. One hundred fecal samples were collected from dogs up to six months of age. Parasites were diagnosed using Willis’, Faust’s and malachite green coproparasitological techniques. Parasite prevalence as determined by Willis and/or Faust diagnostic techniques was as follows: Toxocara spp. 34%, Cystoisospora spp. 28%, Ancylostomatidae 22% and Giardia spp. 8%. These prevalence rates were calculated by considering an animal to be positive if Willis’ or Faust’s or both tests returned a positive result. Cryptosporidium diagnosis with malachite green was negative for all samples. Infection with Toxocara spp., the most prevalent pathogen in this survey, was not limited to dogs with abnormal fecal consistency. The occurrence of asymptomatic parasitized dogs increases the risk of zoonotic transmission.