Serum antibodies in mares and foals to Actinobacillus equuli whole cells, outer membrane proteins, and Aqx toxin.

The research article discusses a study that investigated the antibodies in horses and their offspring against Actinobacillus equuli, a bacterium that can cause serious illness in newborn foals. The research sought to understand whether the antibodies against specific components of the bacterium, including whole cells, outer membrane proteins, and a toxin it produces, were efficiently passed on from mother to newborn.

Research Objectives and Methodology

• The main aim of the study revolved around demonstrating and understanding the transfer of antibodies against Actinobacillus equuli bacteria from mares (mother horses) to their offspring.
• Specifically, the study targeted antibodies against the bacteria’s entire cells, outer membrane proteins, and a toxin known as Aqx.
• The research utilized sera from two distinct mare-foal cohorts, identified as A and B, respectively consisting of 18 and 10 pairs procured in the springs of 2005 and 2006.
• Samples were collected from the mares and the foals at varying moments: immediately after birth prior to nursing, at 12 and 24 hours after birth, and then daily for a week. Another sample was collected from Cohort B after a span of a month from birth.

Findings

• Essentially implicating a successful transfer of antibodies, the mares were identified to possess detectable antibodies against Actinobacillus equuli whole cells and outer membranes at the time of parturition, and the foals subsequently exhibited similar antibodies.
• However, two mares in Cohort A did not initially present antibodies against the Aqx toxin, and their offspring likewise lacked the anti-Aqx antibodies.
• In terms of the relationship between mare and foal antibodies, the study revealed substantial associations (under 5% error probability) between the two for antibodies against whole cells, outer membrane proteins, and the Aqx toxin, 24 hours after birth.
• By the 30th day, it was observed that antibody levels against the three antigen preparations had decreased but not significantly (over 5% error probability).

Conclusions

• This research suggests that Actinobacillus equuli antibodies are effectively transferred from mares to their offspring, with the exception of situations where specific antibodies, such as those against the Aqx toxin, are absent in the mares.
• The study further proposes an effective correlation between the mare and the offspring’s antibodies against specific parts of the bacterium.
• The insignificant reduction in antibody levels over a month suggests that the immunity conferred to the foals could be maintained for a considerable duration after their birth.