Screening for the ciliate Buxtonella sulcata in free-ranging dairy cattle on Terceira Island, Azores archipelago.

Buxtonella sulcata is an alveolate ciliate protist, historically considered a commensal of the gastrointestinal tract of cattle. Despite the fact that its cysts are morphologically identical to those of Balantioides coli, molecular identification techniques have shed new light on its role as a pathogen. This work aimed to assess the presence of this ciliate in the population of dairy cattle on the Azorean island of Terceira by means of molecular analyses (ITS1-5.8S-ITS2 rRNA) of stool samples. A total of 116 samples were collected from adult Holstein-Friesian dairy cows, with no signs of gastrointestinal disease. A proportion of 49.1% of the samples were PCR-positive for Bu. sulcata, and 12 different genetic sequences were identified. These findings highlight the need for future research concerning the factors that influence the presence of Bu. sulcata in the gastrointestinal tract of dairy cows, the role of bovines as possible sources of infection, and the impact this ciliate may have on the health, welfare, and productivity of these animals.