RAHWAY, N.J. — Merck Animal Health recently announced that its Exzolt product is now available for the treatment and control of northern fowl mites in laying hens and replacement chickens in backyard settings.
The product was initially approved by the U.S. Food and Drug Administration for chickens in July 2025 after being assessed by a team of researchers at Pennsylvania State University’s College of Agricultural Sciences.
Northern fowl mites are a persistent external parasite that feed on birds and can quickly affect flock comfort, well-being and productivity, Merck explained in the announcement. Mite infestations can cause challenges for backyard chicken owners, such as bird health, egg production, and the entire home environment.
Mites do not typically live on people or pets, but they can still bite and cause irritation.
Exzolt is an oral solution, where each dose of the product is given in two administrations via drinking water, seven days apart, providing an effective option without the need for injections or individual bird handling, Merck explained.
“Backyard chicken owners need effective parasite control options that are easy to use and protect the health of their birds without disrupting daily care,” Dr. Charles Broussard, Merck Animal Health senior account manager for poultry sales, said. “Exzolt provides a practical, water-based treatment approach with strong efficacy, helping owners manage northern fowl mites while supporting the comfort and productivity of their birds.”
The key benefits of Exzolt include:
- Fast-acting control: starts killing mites within hours to help quickly restore flock comfort as well as prevent the spread to other birds or the household.
- High efficacy: demonstrated 99.9 percent effectiveness in studies and uses the same product formulation as commercial production.
- Reliable treatment: one treatment regimen consists of two doses administered seven days apart for sustained control.
- Convenient administration: delivered through drinking water with no handling required, helping to minimize stress to the birds.
- Reduces spread: prevents mites from spreading to other birds or the household.
- Withdrawal period: zero-day egg withdrawal and 11-day meat withdrawal.
For more information about Exzolt for backyard chickens, visit Merck’s website at www.merck-animal-health-usa.com.
