Fecal strongyle egg counts in horses with suspected pre-clinical pituitary pars intermedia dysfunction before and after treatment with pergolide.

The study was about investigating the impact of Pituitary pars intermedia dysfunction (PPID) and the treatment with pergolide on fecal strongyle egg counts in horses. The study didn’t find significant evidence to support that PPID deteriorates immune function or that pergolide has a significant impact on egg counts in affected horses.

Background of the Study

• Pituitary pars intermedia dysfunction (PPID) in horses is a condition that has been linked to a weakened immune response in older horses.
• Strongyle eggs are a type of parasitic worm egg common in horse populations. Their quantity in feces (fecal egg counts, or EPG) can be a marker of the horse’s immune function.
• The research aimed to investigate if horses with PPID have increased strongyle egg shedding, indicating a weaker immune system, and if the drug pergolide could potentially decrease these counts, therefore improving immune response.

Study Design

• The study was prospective in nature, meaning it aimed to follow up with the subjects over time to study outcomes.
• The researchers tested 48 horses for their Adrenocorticotropic hormone (ACTH) levels and EPG.
• The ACTH hormone test is a standard diagnostic test for PPID in horses.
• They assessed EPG before and after pergolide treatment or placebo.

Results

• At the start of the study, EPG between horses with pre-clinical PPID and healthy controls showed no significant differences.
• There was also no significant difference in EPG between the horses treated with pergolide for PPID and those treated with a placebo.
• This implies that pre-clinical PPID may not significantly impact immune function as measured by EPG, and the treatment with pergolide might not have a significant impact on egg counts in affected horses.

Study Conclusions

• The study did not find substantial support for the hypothesis that PPID has a significant negative effect on the immune system function in horses, as the EPG was not significantly higher in horses with PPID.
• Further, the pergolide treatment did not seem to significantly reduce EPG compared to placebo, suggesting it may not have a clear beneficial effect on immune function as measured by fecal strongyle egg counts.