Promising mastitis treatment to get Wisconsin test run

A new bovine mastitis product that enhances the cow’s immune system and may curb the costliest disease facing dairy farmers will undergo a key trial this year at UW–Madison.

A United States Department of Agriculture (USDA) licensing study will be conducted at UW–Madison’s Charmany Experimental Farm on the mastitis product Quilvax-M, developed by the Massachusetts firm Aquila Biopharmaceuticals, Inc. Aquila has been working with scientists from UW–Madison’s School of Veterinary Medicine since 1993 on developing and testing the product.

Quilvax-M, a new bovine mastitis product that enhances the cows’ immune systems and may curb the costliest disease facing dairy farmers, will undergo a key trial this year at UW–Madison. Mastitis, an inflammation in the cow’s udder, is caused by bacterial infections, the most common culprits being S. aureus and E. coli. The disease tends to lower the productivity of the cow and reduce the quality of the milk. It often strikes the most productive cows in a herd.

“This is one of three studies that will be run in parallel and is based on earlier trials where we were able to demonstrate promising safety, immunogenicity and effectiveness,” says Alison Taunton-Rigby, president and chief executive officer of Aquila, based in Framingham, Mass.

If the licensing study confirms earlier tests, the drug could significantly reduce the estimated $2 billion in annual mastitis-related economic losses, says William Goodger, a UW–Madison professor of veterinary medicine and principal investigator of the trial.

Mastitis, an inflammation in the cow’s udder, is caused by bacterial infections, the most common culprits being S. aureus and E. coli. The disease tends to lower the productivity of the cow and reduce the quality of the milk. It often strikes the most productive cows in a herd.

The UW–Madison site will focus on testing the effectiveness of the product against the S. aureus bacteria. In the past two months, Goodger says the research team has identified 44 Holstein cows from farmers across Wisconsin that fit enrollment criteria for the study. They will be treating the cows with the product and later challenging the animals with the S. aureus bacteria, commonly referred to as “staph.”

Goodger says the product helps maintain the normal quality of the milk. Cows with mastitis tend to produce milk with a high somatic cell count, which are inflammatory white blood cells that greatly devalue the milk.

“In previous trials, we were able to show that the somatic cell counts of the animals stayed relatively normal,” he says.

The staph bacteria are extremely common on Wisconsin dairy farms, and are found to some extent in about 80 percent of the state’s herds. “It’s a chronic disease and farmers have a common line, ‘once a staph cow, always a staph cow,’ ” Goodger says. “We had to sample the bulk milk tanks of 600 herds in Wisconsin to identify 134 farms that had cows testing negative for S. aureus. In the past, farmers have gotten frustrated and culled their cows (with staph),” he adds. “But that’s absolutely the most expensive way to treat the disease.”

Goodger and co-investigators Chet Thomas, a pathobiological sciences professor; and Chris Eisele, a research associate; have collaborated with Aquila since 1993. This new study will be a significant milestone in the project by proving the product’s market benefits and satisfying the USDA’s requirements of safety and effectiveness.

“This has been a wonderful relationship with the farmers, the veterinarians in the field, the UW experts in dairy science and production medicine, and the company,” Goodger says. “This relationship is what has made this research program successful.”

Aquila is a life sciences company developing and commercializing a range of proprietary products which enhance the immune response in animals and humans. Its products are intended for use in treating, controlling and preventing infectious diseases, cancers and autoimmune disorders.

The study will run through spring 2000, and Quilvax-M may become commercially available later next year.