Monitoring piroplasms infection in three cattle farms in Minorca (Balearic Islands, Spain) with previous history of clinical piroplamosis

Bovine piroplasmosis are tick-borne protozoan diseases caused by parasites of the genera Theileria and Babesia. Three Friesian cattle farms (F1-F3) with previous history of clinical piroplamosis were selected in Minorca (Balearic Islands, Spain). Blood samples were collected from 8 to 11 animals every two months throughout a year and, a newly developed multiplex DNA bead-based suspension array based on the Luminex® xMAP technology was used to monitor for the presence of piroplasms. The assay incorporated probes for Babesia divergens, Babesia bovis, Babesia bigemina, Babesia major, Babesia occultans, Theileria annulata and Theileria buffeli, and a Catch-all Theileria and Babesia (TB) control probe. An internal amplification control that was detected with a Luminex probe was also included to monitor for inhibition. Infection was detected in 87.5% of the samples, 38.7% as single infections and 48.8% as mixed infections. T. annulata was widespread in Farm F1, with all animals positive over the whole study; albeit less frequently, T. annulata was also detected in Farms F2 and F3. T. buffeli was the overall most prevalent piroplasm, with a wide distribution in Farms F2 and F3 but only occasionally detected in F1. B. bigemina was the most frequent Babesia species, but was absent from Farm F1. B. bovis, previously reported in Minorca, was only sporadically detected in F2 and F3. A further 3 Babesia species not previously found in Minorca were also identified: B. major present in the 3 farms; B. divergens detected once in 2 animals in F2; and B. occultans found in 4 animals in F2 and in 1 Hyalomma marginatum female tick collected from a positive animal. Sequencing confirmed the identity of B. occultans thus extending the distribution of this species to Mediterranean Europe. This study confirmed the endemic situation for piroplasm infection in the region and detected the presence of a large number of chronic asymptomatic carriers. More importantly, 3 Babesia species not previously detected in the region were detected for the first time.