New short acting antibiotic approved for Canadian farms
Merck Animal Health has announced the Canadian launch of Engemycin DD, a new short acting antibiotic designed for cattle, swine and sheep. Known as MSD Animal Health outside the United States and Canada, the company is introducing this product to help farmers manage bacterial infections in livestock.
Engemycin DD contains oxytetracycline and is classified as a Category III antimicrobial drug, which is considered less critical to human medicine than higher-category antibiotics. This makes it an important tool for veterinarians and farmers seeking responsible treatments that reduce the risk of antimicrobial resistance.
Unlike many existing products, Engemycin DD is the only short acting oxytetracycline available for livestock. This feature is particularly valuable for dairy farmers because it allows treatment of infected cows while maintaining a manageable withdrawal period for milk.
“The launch of Engemycin® DD is significant, especially for dairy farmers in provinces where the use of Category I antimicrobials has been restricted in food-producing animals,” said Ray Reynen, DVM, Veterinary Services, Cattle at Merck Animal Health. “Engemycin® DD gives producers a viable option where they have had limited choices for broad-spectrum antibiotics.”
“Increasing the diversity of veterinary health care tools available in Canada is essential to positive health outcomes for animals and helping farmers play their part in reducing antimicrobial resistance,” said David Wiens, President of Dairy Farmers of Canada. “We welcome the introduction of new treatment options as a positive step towards a more robust set of veterinary health care solutions.”
Merck Animal Health submitted an updated regulatory dossier for Engemycin DD in February 2024. Recognizing the shortage of broad-spectrum antibiotics, Canada’s Veterinary Drugs Directorate granted a priority review, leading to market authorization in February 2025.
Engemycin DD is now available through Canadian veterinarians. Farmers can contact their local veterinarian or Merck Animal Health representative to determine suitability for their livestock and to obtain more information on safe use and withdrawal guidelines.
Photo Credit: pexels-bylukemiller