Exploring a Practical New Way to Determine Anthelmintic Resistance

SUMMARY: Researchers will study whether a combination testing regime for parasite drug resistance can provide a quick and accurate way to determine the best drug therapy to control parasites in horses.

THE PROBLEM: Parasites called strongyles are common in horses and can cause serious health problems, including weight loss, colic, and even death. To control these parasites, horse owners often use deworming drugs. However, over time, these parasites have become resistant to many of the drugs used to treat them. This is known as anthelmintic resistance, and it is a growing problem around the world. Currently, the only approved way to check if a drug is still working is to treat the horse and then test its feces. This method is slow, invasive, and may expose the animal to drugs that no longer work.

THE PROJECT: In this project, the research team wants to develop a better way to detect resistance, faster, easier, in a way that doesn’t expose a horse to unnecessary drugs. The team will test a new approach that combines two advanced diagnostic methods. The first is an in vitro test, the Larval Migration Inhibition Test (LMIT), which measures in the lab how well parasite larvae can move after being exposed to different concentrations of deworming drugs. This helps identify if the parasites are resistant. The second method uses molecular diagnostics to detect specific genetic mutations in the parasites linked to drug resistance. Together, these tools offer a faster, non-invasive, and more accurate way to detect resistance compared to traditional methods. These tests will be done on fecal samples collected from horses in Northern Italy. The team will also collect information from horse owners and stable managers to understand how different management practices may affect the spread of resistance. By the end of the study, the team aims to develop for veterinarians and horse owners a reliable, non-invasive tool to detect resistance.

POTENTIAL IMPACT: This study could help reduce unnecessary drug use and slow the spread of resistance with the goal of controlling parasite infections and thus protect horse health. The methods developed could also be used in other animals in the future, making a step forward for animal health and effective parasite control.