Mastitis Control Program

In an average 100 cow herd, 25 cows can have clinical mastitis per year. Each affected cow has an average of 1.6 cases of clinical mastitis per year, therefore in a 100 cow herd there is approximately 40 cases of clinical mastitis per year. The total cost of a case of mastitis includes both direct costs of up to €128.00 in addition to indirect costs of €90.00 giving an average total cost per case of €218.00.

The main contagious pathogens are streptococcus agalactiae, staphloccus aureus and mycoplasma species. With the exception of some mycoplasma infections these three organisms enter the mammary gland through the teat canal.

The contagious organisms are well adapted to growth and survival in the mammary gland and frequently cause infections lasting weeks and months. The infected gland is the main source for these organisms in the dairy herd, transmission to non-infected quarters and other cows in the herd occurs mainly during milking time.

A streptococcus agalactiae infected cow will show few clinical signs of mastitis, such as abnormal milk but should be suspected if a cow or bulk tank SCC begins to rise and remain high. It infects the cisterns and the ductal system of the mammary gland causing inflammation that is mostly subclinical. It responds to treatment and is cost effective. Staph. aureus produces more damage than agalactiae to milk producing tissue with losses of 45% per quarter and 15% per infected cow. Depending on the age of the cow and SCC history a cow infected with Staph. aureus may need to be culled. Mycoplasma organisms are highly contagious but less common than the other two and can be suspected where outbreaks of clinical mastitis occur that resist treatment.

SCC affects milk quality in reducing the true protein content and lowering the milk lactose rendering the milk less suitable for manufacturing. Also persistent high SCC can result in infertility.

A Good Mastitis Control Program includes:

• Starting with dry cow therapy using a teat sealant to prevent infection.
• Culling chronically infected cows and maintaining a closed herd.
• Management of the dry cow to reduce stress and maximise the immune system through the nutrition program.
• In lactation a healthy teat skin is the first line of defence against mastitis and establishing an active milk quality program .
• Achievable Goals: 0% with Strep. agalactiae and Mycoplasma species and less than 5% infected with Staph. Aureus.

For details on the Mastitis Program offered by CAHL contact your local CAHL Representative today.

CAHL/Nutribio- Nutritionist (Pat O Byrne) BAgSc