Effectiveness of an ivermectin liquid formulation given by nasogastric tube against strongyles in horses.

The study investigates the efficacy of an ivermectin liquid formulation, administered via a nasogastric tube, in treating strongyles in horses, and compared this approach’s efficiency to a paste formulation of the medication consumed orally. The research demonstrates that this method of treatment effectively reduced the presence of strongyle eggs in the horses’ feces, indicating a decrease in infestation.

Study Design and Methodology

The researchers conducted an experiment involving 30 horses. These consisted of:

• 20 horses that were treated either with a liquid ivermectin formulation administered through a nasogastric tube or with an orally consumed ivermectin paste.
• 10 horses that were left untreated to serve as a control group.

All the treated horses received a dosage of 200 micrograms per kilogram body weight. The researchers collected fecal samples from all 30 horses at the time of treatment then every two weeks after for up to 10 weeks.

Analysis of Fecal Samples

In order to analyze the fecal samples, the researchers used the Cornell-McMaster dilution and the Cornell-Wisconsin Double Centrifugation procedures, specifically looking for nematode (worm) eggs.

Results and Conclusions

The study revealed a few significant findings:

• None of the horses that received ivermectin showed any signs of toxicosis (poisoning).
• Strongyle eggs were found in the feces of all horses before treatment.
• In the two weeks following treatment, none of the treated horses had strongyle eggs in their feces, indicating that ivermectin was effective at reducing the parasite load.
• At eight weeks after treatment, most of the treated horses were still mostly free of strongyle eggs.
• By the tenth week post-treatment, most of the treated horses began showing strongyle eggs in their feces again, though generally less than before treatment.

These results seem to suggest that the liquid ivermectin formulation administered via a nasogastric tube effectively reduces strongyle infestation in horses which can provide useful guidelines for treatment strategies in the future. However, the effectiveness diminishes over time, potentially indicating a need for regular 8-10 week treatment intervals.