Molecular epidemiological survey of Babesia species infecting cattle in Paraguay.

Paraguay, an agricultural country in South America, has a high prevalence of tick infestations in its cattle population due to warm temperatures, high humidity, and extensive grazing management practices. Consequently, Babesia infections, which are transmitted by ticks, might have a wide distribution in Paraguay, but the current status of these infections remains uncertain. Therefore, we aimed to assess the infection status of three clinically significant Babesia species, including Babesia bovis, Babesia bigemina, and Babesia naoakii, among cattle populations in Paraguay. Blood samples were collected from a total of 326 cattle across nine departments in Paraguay, and their DNAs were screened with species-specific PCR assays. Of the surveyed cattle, single infections of B. bovis and B. bigemina were detected in 24 (7.4 %) and 127 (39.0 %), respectively, while co-infection with both the parasite species was detected in 38 (11.7 %). In contrast, all of the surveyed cattle were negative for B. naoakii infection. The prevalence of B. bigemina-single infection was higher in the Eastern region (49.0 %) compared to the Western region (34.6 %), in cattle under extensive management (51.3 %) compared to those under semi-intensive management (34.6 %), and in Bos indicus cattle (50.3 %) compared to Bos taurus (15.8 %). Our findings demonstrated a wide distribution of B. bovis and B. bigemina infections among cattle in Paraguay, underscoring the importance of implementing effective control measures to reduce the potential economic losses associated with bovine babesiosis.