Assessment of sewage water as carrier of pathogenic organisms to cattle

Abstract

Water of a brook that receives raw sewage from Jaboticabal, São Paulo State tawn, that passes through the grounds of the UNESP University campus, and, of the well that provides water to the University’s facilities were submitted to bacteriological and parasitological analysis. At the same time, 16 steers aged 8 to 16 months (8 Bos indicus and 8 Bos taurus), were closed in and given one of each type of water to drink (4 to each water source) for seven fifteen day periods. On day zero all the animals were treated with ivermectin (at a dosage of 200 mg/Kg) and were randomly separated in two groups (one for each water source). The experimental cattle came from farms supposedly free of cysticercosis and underwent clinical and laboratorial testing to detect the presence of this parasite before the beginning and at regular intervals during the experiment. After the seven fifteen day period, the 16 steers were slaughtered and were inspected by the “Serviço de Inspeção Federal – SIF” (Federal Inspection Service). Blood and tissue samples were taken from all animals for laboratorial testing. a) the bacteriological tests revealed that the water from the well, classified as drinking water, had fecal coliform levels compatible to the classification as “drinking water” (CONAMA 20), but the water from the brook “Cerradinho” was classified as polluted in all samples; b) the samples taken during the 15 weeks all showed the presence of eggs of Cestode ( Taenia and Hymenolepis) and Nematode ( Ascaris, Trichuris, Capillaria and Ancylostomidae) helminthes; c) while one of eight steers given drinking water from the well was infected with Cysticercus bovis, four of the eight that drank water from the Cerradinho brook were infected; d) although the parasitological tests showed the presence of helminth eggs of Taenia genus, the finding of one animal with positive serum and another with the parasite embedded in its muscle, both from the group that drank the well water, suggest that theses animals were infected at the farm before the beginning of the experiment; e) the serological tests were negative for Leptospira spp, Brucella spp, Neospora canimum and Toxoplasma gondii, indicating that these pathogens were not transmitted to the animals. Laboratorial tests with mice, to verify the presence of Toxoplasma gondii, confirmed the serological tests; f) the results obtained by the serology tests and those of the Federal Inspection Service showed only 6.25% of agreement.