Bayer’s Baytril® 100 (enrofloxacin) Injectable FDA approved to fight BRD associated with Mycoplasma bovis

Leading antimicrobial now labelled for single-injection treatment of all major BRD pathogens including Mycoplasma bovis

SHAWNEE, Kan. (June 2, 2011) – Baytril® 100 (enrofloxacin) Injectable, manufactured by Bayer Animal Health, has been approved by the Food and Drug Administration for treatment of Mycoplasma bovis — a major pathogen for Bovine Respiratory Disease (BRD) that has a significant health and economic impact on cattle operations across the country.

“Mycoplasma bovis is often overlooked, but can be a very opportunistic and damaging pathogen,” said Dr. Fiona Maunsell, of the College of Veterinary Medicine, University of Florida. “It presents itself in a wide range of clinical manifestations, including mastitis and respiratory, ear and joint infections. Early diagnosis and treatment is critical with Mycoplasma bovis to prevent irreparable damage.”

Mycoplasma bovis is a slow-growing, very contagious infection that is easily spread throughout herds via nose-to-nose contact, contaminated water and feed and, even inhaled by calves as they suckle dams shedding the infection. Symptoms can be similar to other BRD indicators, such as coughing, depression and fever, but also can include head tilt, ear droop and ocular and nasal discharge. Recent data have shown that Mycoplasma bovis plays a larger role in respiratory and other infections in beef cattle than previously thought, with an estimated $32 million a year in damage to the United States beef industry, primarily through losses in weight gain and carcass value1.

With this approval, Baytril® 100 (enrofloxacin) is now labelled and proven effective as a single-injection treatment for all major pathogens of BRD in cattle and non-lactating dairy heifers less than 20 months of age, including Mannheimia haemolytica, Pasteurella multocida, Histophilus somni and Mycoplasma bovis.

Clinical field studies of single-injection treatment efficacy results against Mycoplasma bovis indicate Baytril® 100 was effective on more than 70 percent of calves treated by Day 6; and 88 percent of calves treated with Baytril® 100 were considered continued successes on Day 102.

“Baytril® 100 has long been valued by veterinarians and producers as a quality single-dose therapy for BRD,” said Dr. Cary Christensen, Senior Director, Food Animal Products Business Unit at Bayer Animal Health. "With the approval of Baytril® 100 for treatment of the critical pathogen Mycoplasma bovis, they now have assurance that using Baytril 100 as their first line BRD treatment can provide the results needed for an efficacious response to the infection.”

Baytril® 100 has been the choice for many bovine veterinarians and beef cattle producers since its introduction in 1998 and is the largest-selling, single-dose antibiotic in its class. The first FDA-approved fluoroquinolone antimicrobial for use against BRD, Baytril® 100 is a proven and effective management product.

For more information about Baytril® 100, call Bayer Veterinary Services at 1-800-422-9874 or visit

Federal law restricts this drug to use by or on the order of a licensed veterinarian. Extra-label use of this product in food-producing animals is prohibited.

Do not use in female dairy cattle 20 months of age or older. Use of enrofloxacin in this class of cattle may cause milk residues.

About Bayer Animal Health

Bayer HealthCare, a subsidiary of Bayer AG, is one of the world’s leading, innovative companies in the healthcare and medical products industry and is based in Leverkusen, Germany. The company combines the global activities of the Animal Health, Consumer Care, Medical Care and Pharmaceuticals divisions. Bayer HealthCare’s aim is to discover and manufacture products that will improve human and animal health worldwide. With sales of EUR 977 million (2009), Bayer’s Animal Health business is one of the world’s leading manufacturers of veterinary drugs. The division manufactures and markets approximately 100 different veterinary drugs and care products for food-supplying animals and companion animals. U.S. Headquarters for Bayer Animal Health is located in Shawnee, Kansas.


1. Kumar A, Verma AK, Rahal A. Mycoplasma bovis, a multi disease producing pathogen: an overview. Asian J Anim Vet Adv. 2011; 6(6):537-546.

2. Bayer Animal Health, data on file.