Epidemiological investigation of cryptosporidiosis in dairy cattle in Guangxi,China

To investigate the prevalence of cryptosporidiosis in dairy cattle in Guangxi Province,Cryptosporidium oocysts were collected by the Sheater's sugar flotation technique and the modified acid-fast stain method from 1 612 fecal samples which were collected from nine Holstein dairy cattle farms and four individual Holstein dairy cattle farms.The Cryptosporidium oocysts were then identified using the PCR-RFLP based on the 18S rRNA gene.Results showed that the infection rate of Cryptosporidium was 11.72%(189/1 612),distributed in seven Holstein dairy cattle farms.The infection rate of Cryptosporidium in 1-6-month-old cattle was 21.3%,which was significantly higher than that in 7-12-month-old cattle(9.6%) and above 1-year-old cattle(3.8%)(P0.01).The infection rate of Cryptosporidium in winter was higher than that in summer,however,no significant difference was found(P0.05).PCR-RFLP analysis suggested that seven Cryptosporidium isolates all belonged to Cryptosporidium andersoni.The results indicated that the C.andersoni was the predominant species of Cryptosporidium in dairy cattle in Guangxi.The infection rate of Cryptosporidium in dairy cattle was similar to that in Henan,Jiangsu,Anhui,and Jilin provinces.