Cattle, Rhipicephalus microplus and Babesia bigemina

Three splenectomized naïve Holstein calves ({"type":"entrez-nucleotide","attrs":{"text":"C46527","term_id":"2382780","term_text":"C46527"}}C46527, C1437 and {"type":"entrez-nucleotide","attrs":{"text":"C46541","term_id":"2382794","term_text":"C46541"}}C46541) approximately 4 months old and confirmed to be Babesia-free by competitive enzyme-linked immunosorbent assay and nested PCR (Goff et al., 2006; Suarez et al., 2012) were used for feeding R. microplus, the La Minita strain. Approximately 40,000 larvae were applied under a cloth patch on the dorsal region for acquisition of B. bigemina parasites. Fourteen days after tick application, when approximately 1% of the ticks had molted to unfed adults, ~10⁷ B. bigemina infected erythrocytes, the Mexico strain, were inoculated intravenously into each calf to synchronize female tick acquisition feeding with an ascending B. bigemina parasitemia (Bohaliga et al., 2019). The presence of B. bigemina in the blood was determined by Giemsa-stained blood smear.