Investigation of a Cryptosporidiosis Outbreak Caused by Cryptosporidium parvum in a Dairy Farm

Abstract

Background Diarrhea caused by parasitic agents is common in neonatal calves and causes significant economic losses in cattle farms worldwide. Cryptosporidium spp. is one of the most frequently detected parasitic agents causing diarrhea in neonatal calves. Also, Giardia intestinalis is shown to cause diarrhea in calves. This study aimed to investigate the presence of Cryptosporidium spp. in calves (n:36), cows (n: 11), drinking water and two different artesian water supplies as well as in environmental swap samples (n:32) obtained from the manger, silage, bottle, and doorknob in a dairy farm which has big diarrhea problems. For this purpose, all fecal samples investigated with using direct microscopy for routine parasitological screening. Then, the presence of Cryptosporidium spp. was examined in feces samples and other environmental samples using Kinyoun acid-fast stained slides and Real-Time PCR targeting Cryptosporidium spp.. In addition, Real-Time PCR positive samples were investigated by nested PCR and subsequently by sequencing, BLAST, and phylogenetic analysis for species identification by MEGA7. Results Giardia intestinalis was detected in 10 feces samples (21,27%; 10/47) during routine microscopic examination. Among them, 9 belonged to calves older than two months without diarrhea, and one belonged to an adult cow. Cryptosporidium spp. was found in 11 calves (30.55%; 11/36) by Real-Time PCR, whereas no cows were found positive. Among the PCR positive samples, only five of them were detected as positive by microscopy. Cryptosporidium spp. positivity value was found higher in younger than two month old calves with diarrhea (9/12; 75%). Also, Cryptosporidium spp. was found in one of two water supplies and five of environmental samples by real-time PCR. Of the 18 real time positive samples, 8 were found positive by nested PCR and all positive samples were detected to be Cryptosporidium parvum by sequencing, BLAST, and phylogenetic analysis. Conclusions Our findings showed the importance of C. parvum infection in diarrhea cases occurred in calves. Besides the correct diagnosis and treatment of Cryptosporidium spp. contaminated water resources, and hygiene measures are very important for preventing the cryptosporidiosis in dairy farms.