First report on the molecular prevalence and associated risk factors of spp. in dairy cattle in Khon Kaen, Thailand.

BACKGROUND AND AIM

Bovine coccidiosis, caused by the protozoa , is an important parasitic cattle disease that affects animal health and has economic impact worldwide. This study was conducted to report the first molecular prevalence and genetic diversity of spp. in dairy cattle in Khon Kaen province, Thailand, and to identify the risk factors associated with spp. infection.

MATERIALS AND METHODS

From July 2020 to October 2021, 296 fecal samples were collected from dairy cattle divided into three age groups, including <3-month-old calves, 3-month-old to 1-year-old calves, and >1-year-old cattle. spp. were identified by multiplex polymerase chain reaction (PCR) amplifying 18S RNA gene and confirmed by DNA sequencing. Information regarding all associated risk factors was collected using questionnaires and analyzed using logistic regression tests in the Statistical Package for the Social Sciences program.

RESULTS

Polymerase chain reaction results showed that 104 (35.13%) of 296 samples were positive for spp. The <3-month-old calves (46.51%) had the highest infection rate. Moreover, multiplex PCR identified five species of , namely, (32.69%), (18.26%), (5.76%), (3.84%), and (2.88%). An association was observed between risk factors and spp. incidence (p < 0.05). DNA sequencing revealed the similarity of each spp. with 91%-100% nucleotide identity. Phylogenetic tree analysis demonstrated the close relationships of clusters of and , , and and another cluster of .

CONCLUSION

The results confirm that spp. are commonly found in dairy cattle, especially calves. The molecular test could be powerful for species identification. This study also provides epidemiological information for developing future strategies to control bovine coccidiosis.