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 Knowledge for the CommonWealth

Antibiotics are still a good choice for use in the treatment of certain cases of mastitis.

Dairy Pipeline: September 1996

by Tom Bailey
Dairy Production Medicine
Virginia-Maryland Regional College of Veterinary Medicine
Virginia Tech

The use of such agents are based on culture of mastitis organisms and the sensitivity of those organisms to a specific antibiotic. Unfortunately, the majority of mastitis is treated based on historical farm use of a particular drug and the previous responses demonstrated. Only antibiotics that have been approved for use in the udder, packaged in a sterile single commercial teat infusion tube, and are sold as a lactating cow preparation should be used in the treatment of mastitis in the quarter. The use of other medications sold for use in the quarter, delivered in syringes and administered by infusion cannulas, drawn from large multi-dose bottles, or delivered in plastic "squeeze jets" is asking for antibiotic residues or the potential introduction of severe mastitis causing organisms in the quarter. These products have not been processed in a sterile environment and may be harboring mastitis causing bacteria. Oxytocin is also used as an adjunct to therapy in cases of mastitis. The treatment of mastitis with frequent strip-outs and oxytocin is a tremendous tool for some cases of mastitis. Oxytocin has been approved for use in this manner by the Food and Drug Administration, however, it is not approved for use as a production enhancement drug. This means that it should not be routinely used in cows on a daily basis, but only as a means of therapy for mastitis or in early lactation with udder edema. The use of oxytocin for increasing production is a direct violation of the Food, Drug and Cosmetic Act and the user could be prosecuted. Gentamycin (Gentocin®) is regrettably another drug still frequently infused in mastitis cases. The AABP, a 5,000 member organization of cattle veterinarians, has requested that all use of gentocin in food animals cease. The reason for this stoppage is because gentocin residues are found in the cow 18 months after administration. There is not a cow anywhere that is not susceptible to slaughter in the next 18 months. Violation of antibiotic residues is a significant problem in the cattle industry and especially in cull dairy cows. Residue violations are a "blackeye" on the entire dairy industry and only add to the growing concern by consumer groups. Use antibiotics and other drugs responsibly and recognize the consequences of any drug you are administering. Follow the label directions for milk and meat withdrawal and check with your local veterinarian for recommendations concerning the responsible use of any drug in dairy cows.

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