Detection of equine Babesia spp. gene fragments in Dermacentor nuttalli Olenev 1929 infesting mongolian horses, and their amplification in egg and larval progenies.

This study investigates the presence of equine Babesia genes in a specific tick species infesting Mongolian horses. The research indicates that these ticks may play a significant role in the transmission of equine babesiosis in this region, with evidence of transovarial transmission.

Methodology

• The research was undertaken with blood samples from horses in Altanbulag, Tuv Province, Mongolia. The team also examined Dermacentor nuttalli ticks in different stages of their life cycle. This included partially fed-females as well as their egg and larval progenies.
• The presence of Babesia parasite DNA in the samples was detected using a technique called polymerase chain reaction (PCR). This method amplifies a particular DNA sequence, making it easier to identify specific gene fragments of the Babesia species, in this case, Babesia equi (EMA-1) and Babesia caballi (BC48).
• Following the initial PCR test, a nested PCR test was conducted to confirm positive cases. Nested PCR is a modification of PCR that is used to improve amplification and specificity. It involves two sets of primers used in two successive PCR runs.

Findings

• Babesia parasite DNA was detected in some of the horse blood samples during the initial PCR testing.
• Notably, all positive detections of Babesia in the tick samples were confirmed by the nested PCR. This was consistent across all stages of the ticks’ life cycle, from partially fed-female adults through to eggs and larvae.
• The findings bolster previous research results that detected Babesia DNA in Dermacentor nuttalli ticks in Central Mongolia. Together, they suggest that this tick species likely plays a vital role in the transmission of equine babesiosis in Mongolia.
• Moreover, the discovery of parasite DNA in tick eggs and larvae raises the possibility of transovarial transmission. This refers to the process where a female tick passes on the parasite to her offspring through the eggs.

Significance

• This research adds significant value to our understanding of the lifecycle and transmission of the Babesia parasite, especially in equines.
• Understanding the ways the parasite is transmitted can be instrumental in controlling the spread of equine babesiosis. Current prevention strategies may have to be re-evaluated to take transovarial transmission into account.
• The findings have particularly pertinent implications for horse health in Mongolia, pointing to the need for targeted interventions against Dermacentor nuttalli ticks.