Vet Watch: Tailoring mastitis treatment

When clots are spotted in the milk of a particular cow, it can be easy to reach for the box of lactating cow tubes and start treatment and then carry on regardless.

However, have you ever wondered if you have made the right decision in your treatment? With so many different products on the market how do you know the right ones are being used?

All farms are different and a regime working on one farm may not be the most suitable and effective against the major mastitis pathogens on other farms. Although educated guesses can be made, there is no way to tell which bug is causing mastitis without taking a sample for laboratory analysis.

Therefore, it’s vital the vet is closely involved in the treatment of mastitis cases as they may have information from previous samples taken on farm. This does not necessarily mean calling your vet in to treat every case, but advice should be sought in persistent cases. Also if the animal is showing signs of systemic disease, for example, if it has a high temperature and is off food, intra mammary tubes alone may not be enough to sort out the problem. In these cases vet help should be called for.

In my opinion every case of mastitis should be sampled before treatment. Although every sample may not be tested, having a store of previous cases could prove invaluable should major problems arise. Adding 1-2ml of glycerol to the sampling pot will allow samples to be stored in deep freeze until needed.

It can be difficult avoiding contamination when sampling and vet advice should be sought to do this effectively. With practice it should become second nature. Preparation of the quarter before sampling is key. The quarter should be washed, disinfected with iodine, dried, sterilised using surgical spirit and then sampled.

When should samples be tested?

• Test animals not responding to treatment and those chronically infected
• Test animals with persistently high somatic cell counts more than 250,000
• Test animals if bulk somatic cell count is approaching or more than 250,000
• Test animals if treating more than 30 cases in every hundred cows a year (remember two quarters equal two cases)

One case of mastitis on average is estimated to cost about £137.31, with severe or fatal cases inevitably costing more. Armed with these facts it’s important when treating cases to use the correct products tailored to individual farms or this figure will rise even further.

Measures to control infection rates are different depending on which pathogens are responsible. Generally they are split into contagious and environmental. Contagious agents are mostly spread in the parlour and environmental pathogens in the housing.

Do you know which is more prevalent on your farm?

Management in the dry period also plays a significant role. Current thinking suggests sub-clinical infections picked up in this period may result in an increase in clinical cases in the first part of the lactation. Consequently, if the majority of clinical cases occur within the first 30 days of lactation then the dry cow period should be looked at as a potential source of infection.

Dry cows and maiden heifers are often out of sight and out of mind until they approach calving. The management of these animals is pivotal in stemming the flow of new infection within the herd. Changes in management may include alternative housing, addressing mineral/nutritional deficiencies and the introduction of teat sealants to the drying off regime.

The introduction of double tubing with dry cow therapy followed by an internal teat sealant has also been shown to have a beneficial effect on new infection rates.

Many tube manufacturers all claim to have the answer to mastitis problems, but the truth is therapy must be tailored to individual farms. And without sufficient testing money can be wasted on ineffective treatments. Control measures must be implemented at all stages of management including the dry period.

Although it may be unrealistic to eradicate mastitis from herds, don’t pay for ineffective treatment or disease that could be prevented.