Contagious Mastitis


1 min read

How is it spread Staphylococcus aureus

Contagious mastitis in cows is often spread during milking. You can minimise the spread by maintaining healthy teat ends, using well-operating milking equipment, and disinfecting teats after milking. Use the practical guidelines and technical notes for information on stockmanship, teat washing, pre-milking disinfection, calm routines for attaching cups, and methods to avoid teat damage. Adhering to these practices helps to control the spread of mastitis and ensure the well-being of your cows.

How is it spread?

Contagious mastitis is usually spread during milking. Milk from an infected quarter can be spread to the teat skin of other quarters and cows by dirty hands or gloves, teat cup liners, and cross flow of milk between teat cups. Hygienic practices at milking time help reduce this type of mastitis. Use good milking technique and a consistent routine. There are different types of bacteria that cause contagious mastitis, see Technote 5 on the best ways to deal with them.

Use a good milking technique

Practice using good stockmanship skills to encourage milk let-down and establish a
calm, consistent routine for attaching cups. Know how to strip cows to detect abnormal milk. Always put cups on clean and dry teats. Ensure you have a good teat washing and pre-milking disinfection routine, along with a practiced method of taking cups off that prevents team damage and over milking

Guideline 5 provides practical information on:

  • Stockmanship to encourage milk let-down
  • Foremilk stripping cows to detect abnormal milk
  • The importance of putting cups on clean, dry teats
  • Teat washing and pre-milking disinfection
  • Establishing a calm, consistent routine for attaching cups
  • Method for taking cups off
  • Selecting an end-of-milking point
  • Teat damage caused by over milking.

Technote 5 provides technical information for farmers and advisers on:

  • Different types of bacteria that cause contagious mastitis, and the best ways to deal with them
  • Other tests for detecting mastitis
  • Ideal dairy water quality to enable hygienic practices
  • Udder flaming technique
  • Eliminating the practice of machine stripping
  • Shorter milking times and Max T principles.

Staphylococcus aureus

Staphylococcus aureus is a common cause of mastitis. Most herds will have some cows with Staph. aureus infections. With good management, these bacteria have minimal impact. But if not well managed, infections may spread from cow to cow.

  • A bacterium commonly found on skin, in nasal cavities and other sites, of cows and people.
  • Can transfer from cows to people (zoonosis) and from people to cows.
  • About 85% of herds have some cows with these bacteria in their udders.
  • Usually makes up less than 10% of clinical mastitis cases but can be more during outbreaks.

Download the Staphylococcus aureus mastitis management factsheet below:

Last updated: Sep 2023
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