New findings of ciliates Buxtonella sulcata in the faeces of cattle from northern regions of Russia and comparative analysis of Buxtonella species.

Buxtonella sulcata is a common ciliate that inhabits the intestines of cattle and can cause diarrhea and other clinical signs of infection. The distribution of B. sulcata in Russia has been practically unstudied, while the buxtonellosis it causes can have a negative impact on the health of cattle. This study aimed to morphologically and molecularly identify cysts and trophozoites of B.sulcata. This study provides data on the first finding of infection with B. sulcata ciliates in cattle from two northern regions of Russia. The structural features of B. sulcata were studied using immunofluorescence microscopy and silver impregnation methods. The phylogenetic position of the studied isolates was determined using sequences of the SSU and ITS regions. The results of our comprehensive comparative analysis revealed distinct features that enable the differentiation of species within the genus Buxtonella.