Contagious mastitis is caused by bacteria such as Staph. aureus and Strep. agalactiae that are transmitted between cows during milking. Occasionally Strep. uberis and Strep. dysgalactiae (normally classified as environmental pathogens) can also be transmitted between cows during milking.
Environmental mastitis is caused by bacteria such as Strep. uberis and E. coli. The primary source is faeces and mud so wet and dirty conditions are a risk for this type of mastitis.
Prevention of environmental mastitis involves minimising build-up of mud and manure in the cow's environment to keep udders and teats clean and healthy. This applies especially to areas with high cow traffic, such as water troughs, gateways, collecting yards, feed pads and housing systems.
Subclinical mastitis during lactation can also be caused by bacteria known as the minor pathogens such as CNS and C. bovis.. These bacteria usually cause subclinical mastitis and contribute to a cow's rise in SCC towards the end of the lactation. They are often found on the skin of the cow so prevention is through good teat disinfection after milking.
Guideline 5 - Use good milking technique and a consistent routine. Contagious mastitis is caused by bacteria such as Staph. aureus and Strep. agalactiae that are transmitted between cows during milking. Occasionally Strep. uberis and Strep. dysgalactiae (normally classified as environmental bacteria) can also be transmitted between cows during milking.
Guideline 6 - Monitor and maintain milking machine function. Milking machine equipment has been designed to harvest milk efficiently and maintain healthy teats. Teats are attached to milking machines for 50-100 hours per lactation. Machines that are not functioning correctly can contribute to new mastitis infections.
Guideline 7 - Use post milking teat disinfection on every teat after every milking. After milking, bacteria multiply on the teat skin and may extend into the teat canal. If the whole surface of each teat is disinfected immediately after milking, this spread can be minimised. Teat disinfection also helps to keep teat skin supple and healthy.
Guideline 8 - Practise good hygiene during milking. Bacteria are present in milk from all infected quarters. They are spread to other quarters and cows by splashes or aerosols of milk that occur during stripping, by milkers’ hands, teatcup liners and by cross flow of milk between teatcups.
Guideline 9 - Manage teat sores and cracks. Healthy teat skin is easier to keep clean, minimises preparation before milking, and minimises the risk of new infections occurring.
Guideline 10 - Rapidly find, record and treat clinical cases. Clinical cases of mastitis are costly and significantly disrupt the milking routine. Clinical cases that are missed can dramatically increase the bulk milk SCC because they produce very high numbers of somatic cells. Rapid detection and treatment of cases means fewer chronic infections develop, and less chance of infection being passed to other cows.
Bulk Milk SCC
Guideline 11 - Monitor bulk milk SCC. The Bulk Milk SCC (BMSCC) is an indirect way of estimating the level of subclinical mastitis in the herd. For herds with a BMSCC of 300,000 cells/mL or less, each 100,000 cells/mL indicates approximately 15% of cows are infected.
Individual Cow SCC
Guideline 12 - Use individual cow SCC for management decisions. Regular individual cow SCC enable you to monitor udder health of each cow over a lactation. They allow you to assess the contribution of an individual cow to the bulk milk SCC, if problems arise.
Guideline 13 - Seek professional advice if problems persist. Trained advisors are available in all regions to investigate and help you solve your mastitis and milk quality problems. A team approach is often required because solutions require the expertise of different professionals.