First molecular detection of Anaplasma marginale, Babesia bovis, and hemotropic Mycoplasma spp. in bovine colostrum.

Bovine colostrum (BC) is widely recognized for its fundamental role in the nutrition and protection of newborn calves. However, it may also contain pathogens, and research is still limited to a few agents. This study aimed to assess the presence of Anaplasma marginale (msp4), Babesia bovis (cytb), B. bigemina (cytb), and hemotropic Mycoplasma spp. (hemoplasmas) (16S rRNA or gapN) in BC and blood by molecular investigation. Aseptically collected blood (5 mL) and colostrum (40 mL) were obtained once from 104 Holstein cows from a commercial dairy herd in southern Minas Gerais, Brazil, within the first 24 hours after parturition. Blood analyses by PCR revealed the frequencies of 95.19% (99/104) for A. marginale, 62.5% (65/104) for B. bigemina, 52.88% (55/104) for B. bovis, and 74.85% (82/104) for hemoplasmas. The most prevalent blood co-infection was A. marginale plus hemoplasmas. The investigation in BC by PCR showed that the agents were present in 22.12% of the samples, with frequencies of 12.12% (12/99) for A. marginale, 10.91% (6/55) for B. bovis, and 6.1% (5/82) for hemoplasmas. No co-infection was identified. These findings highlight the relevance of management for control of the hemopathogens, and demonstrate the need for further investigation into the viability of the microorganisms and their epidemiological role, once the vertical transmission is an important route for some pathogens.