DairyCo

Mastitis

Mastitis is inflammation of the mammary gland most commonly caused by micro organisms that invade the udder. These organisms, usually bacteria, multiply and produce harmful toxins. There are more than 100 bacteria that cause mastitis and it has two forms, clinical and sub clinical.

Clinical mastitis signs vary from seeing a few clots in the milk with perhaps some swelling of the infected quarter to severe signs which include swollen quarter or whole udder. The cow may have a high temperature, fever, loss of appetite, and be dehydrated.

Sub clinical mastitis is when there is infection present with no clinical signs. The cow would have a raised somatic cell count (number of white blood cells/ml of milk) and there may be bacteria in milk cultures. The UK uses a threshold of 200,000 cells/ml of milk to decide whether a cow or quarter is infected. Care has to be taken when using this figure as a cow could have a cell count just below 200,000 and have ¾ with a cell count of less than 50,000 and ¼ with a cell count well over 200,000.

Economic losses from mastitis range from lost milk quality bonuses to quality penalties for high cell count milk from milk buyers to the costs associated from treating mastitis and having to throw away un saleable milk. The cost of treating a case of mastitis averages £250-£300, varying from around £60 to treat a mild case of mastitis to the cost of the loss of a cow following a severe case of mastitis.

DairyCo has recently launched the DairyCo Mastitis Control Plan, a bespoke plan for individual farms depending on the farm's own circumstances. A detailed survey of the farm is undertaken along with analysing milk bacteriology, disease patterns from monthly milk recording, somatic cell count data and clinical mastitis information. From the interpretation of this information, the farm is given a plan to combat mastitis. This is then reviewed on a regular basis, probably every six months, as it takes time from implementation of the plan to see success. Trial work showing full compliance with the advice resulted in a 36% reduction in mastitis, with two thirds compliance with the advice resulting in a 20% reduction in mastitis.