Evaluation of Treatment With Respiratory Gene Technology and Serum in a Group of Standard Bred Racehorses With Cytological Evidence of Mild Equine Asthma.

The study investigates the effectiveness of a novel method, targeted at reducing bronchoalveolar lavage (BAL) neutrophils and mast cells, as a potential alternative treatment option for mild equine asthma. The study found that both the Respiratory Gene Technology (RGT) and serum treatments were effective in reducing these cells.

Objective and Methodology

• The primary objective of this research was to test an alternative treatment for glucocorticoids in treating equine asthma. The need for this study arose because of the prolonged withdrawal time associated with the use of glucocorticoids.
• The researchers used both RGT and serum treatments, with a commercial kit available to produce autologous conditioned serum. They aimed to understand if these treatments could effectively reduce the number of BAL neutrophils and mast cells in racehorses suffering from mild equine asthma.
• The study adopted a randomized clinical trial structure, involving 36 Standardbred trotters in active training. The horses were divided into three groups – a healthy control group, an RGT group, and a serum group, with each group consisting of 11-13 horses.

Procedure, Observations and Results

• Initial tests including a TW and BAL were performed before starting the treatment. Subsequent tests took place after a 6-week treatment period, which included 12 intramuscular injections of either RGT or serum. The horses were followed up 10 weeks after the conclusion of treatment.
• The results indicated significant decreases in BAL neutrophils for both the RGT and serum groups between before and after treatment (T0 and T6). Further, a significant decrease in BAL mast cells was observed for both the treatment groups.
• However, the researchers did not find any significant difference in tracheal wash (TW) cytology at any time-points. Pro- and anti-inflammatory cytokines were regulated according to the treatment, and the control group show no differences at any points.

Conclusion

• The study concluded that treatments using both RGT and serum were effective in reducing the presence of BAL neutrophils and mast cells in horses with mild equine asthma.
• The authors further suggest that large-scale follow-up studies would be necessary to confirm these findings and to potentially develop and confirm these methods as an effective alternative treatment option for mild equine asthma.