[Effect of a paramunity inducer on the incidence of diseases and the plasma cortisol content in Thoroughbred foals before and after weaning].

The research investigates the influence of a prophylactic medication, Baypamun, on the prevalence of diseases and changes in blood cortisol levels in Thoroughbred foals during weaning. The findings suggest that Baypamun may reduce respiratory infections and impact cortisol responses in foals.

Study Design and Methods

• The study involved 63 Thoroughbred foals from four different studs. These foals were the subjects of a blind test, meaning neither the experimenters nor the handlers knew which foals received the actual treatment and which received a placebo.
• Baypamun, known as a paramunity inducer, was given to 38 of these foals at two specified time points before weaning and once after weaning. A placebo was administered in the same manner to the remaining 25 foals.
• Over three weeks, the researchers monitored the foals, specifically looking for signs of respiratory infections.
• In addition, they sampled and measured the cortisol levels in the blood plasma of 53 of the foals both before and 24 hours after weaning. Cortisol is a hormone often associated with stress response, thus serving as an indicator of how stressful the weaning process was for the foals.

Study Findings and Interpretation

• During the three-week observation period, the study found a lower incidence of respiratory infections in the foals treated with Baypamun (7.9%) than those given the placebo (24%). This suggests that Baypamun may function as an effective preventative measure against these infections.
• Changes in cortisol levels revealed interesting findings. The concentration of cortisol increased in all foals after weaning—an expected result considering the stressful nature of the weaning process.
• However, there was a significant difference in the cortisol increase between the two groups. In the Baypamun-treated foals of one stud, the increase was statistically significant, whereas the cortisol increase was significant in the placebo-treated foals of all studs. This could imply that the Baypamun may have lessened the stress response during weaning, as indicated by the cortisol levels, in a majority of the treated foals.
• Nevertheless, the fact that the decrease in cortisol level significance was observed only in one stud implies that other factors could affect the physiological stress responses of foals, or the effectiveness of Baypamun could vary across different environments or management practices.