The impact of different equine influenza vaccine products and other factors on equine influenza antibody levels in Thoroughbred racehorses.

The research paper studies the usage of equine influenza (EI) vaccines in training yards, how various factors influence the immunological response to these vaccines, and how to decide on effective vaccination strategies based on the gathered evidence. The findings reveal that the horse’s sex, number of vaccine doses administered, and the variety of vaccine products used are essential factors that determine the EI antibody levels in Thoroughbred racehorses.

Research Methodology

• The research was an observational field study involving 102 Thoroughbred horses in active training on a single site.
• Vaccination records from the official passports of each horse were thoroughly analyzed to understand their vaccination histories.
• Blood samples for antibody testing were collected by a veterinary surgeon a month after administering a booster shot with ProteqFlu-Te, an influenza vaccine for horses.
• The antibody levels against equine influenza were measured using Single Radial Hemolysis (SRH), a standard serological test for detecting antibodies.
• A multivariate statistical analysis was used to identify the factors that affected the levels of SRH antibody titres.

Results

• Analysis of the data indicated a strong correlation between the horse’s age and the number of vaccine doses received.
• Over 70% of horses got their first vaccine dose when they were between 6 and 12 months old.
• On average, horses had received 6 vaccine doses, and the average interval between booster vaccinations was 7.7 months.
• Almost all horses (95%) got more than one influenza vaccine product, while 32% were given three different vaccine products.
• Higher antibody levels were significantly observed in female horses than in males, indicating a substantial association between the horse’s sex and the antibody levels.
• There was also a significant association between the number of different vaccine products administered and the EI antibody levels.
• Interestingly, the study demonstrated a negative correlation between the number of vaccine doses and the levels of EI antibodies as measured by SRH.

Conclusion

• The study concluded that the principal factors influencing the levels of EI antibodies in racehorses are the horse’s sex, the number of vaccine doses received, and the variety of vaccine products administered.
• This research provides valuable insights and necessary evidence to design effective vaccination strategies for equine influenza in Thoroughbred racehorses.