Concordância entre a técnica parasitológica e nPCR na detecção de Cryptosporidium spp. em amostras de fezes de bovinos leiteiros infectados naturalmente

Abstract

Cryptosporidiasis is a zooanthroponic disease caused by protozoa of the genus Cryptosporidium. Its transmission is via fecal-oral route through the spread of sporulated oocysts in the environment by infected hosts, contaminating water and food. This study aimed to evaluate the occurrence of Cryptosporidium spp. in fecal samples of dairy cattle from three different farms. The data were obtained through the analysis of cattle feces samples that were submitted to the modified Ziehl-Neelsen technique and to the process of purification and extraction of DNA through Nested-PCR. From 344 samples analyzed, it was possible to observe the positivity in 31.7% samples by the ZNm technique. Of these positive samples, 28 were submitted to nPCR, of which 20 (71.4%) were positive in this technique. Although molecular techniques are more sensitive, they have limitations. Failure to amplify eight samples may result from the presence of inhibitors. Positive nPCR samples were saved for species identification at another time. The prevalence of Cryptosporidium in cattle is approximately 1/3 of the studied sample, which can cause significant economic losses due to reduced milk production if control, prevention and treatment measures are not taken.