Friday, 18 September 2020 10:55

Managing mastitis and bulk somatic cell counts

Written by  Staff Reporters
Teatspray after every milking to keep mastitis under control. Teatspray after every milking to keep mastitis under control.

Mastitis is the inflammation of the mammary gland.

In cows it is usually caused by bacteria which have entered the teat canal and moved up into the udder. The bacteria multiply and cause a mastitis infection which can result in an inflamed udder. Teatspraying is done to kill bacteria before they enter the udder causing infection. Bacteria do increase in numbers after the milk has left the cow especially in the right conditions. This can cause bacto grades.

What are somatic cells?

When bacteria enter the udder, the cow responds by sending large numbers of white blood cells to the mammary gland and into the milk. The white blood cells surround and destroy the bacteria. They are one of the most important defence mechanisms the cow has to fight udder infection. All these cells are from the cow’s body – they are not bacterial cells. Teatspraying has no short term effect on somatic cells. Teatspraying is an important part of a long term strategy in reducing bulk somatic cell counts.

Why teatspray?

• To reduce the number of bacteria on the teat surface by up to 99% and kill bacteria before they enter the udder through the teat canal.

• To reduce the number of new infection rates of mastitis by up to 50%.

• To promote healthy teat condition.

How can we get the best from our teatspray?

• Teatspray at every milking and as soon possible after the cups are removed.

• Mix the teatspray to the manufacturer’s recommendations for the conditions at the time.

• Check your water quality to ensure the compatibility of your teatspray to your water supply.

• Know the level and type of emollient in your current teatspray solution (there may not be any).

• Additional emollients can be added to the mix but should not exceed 20% of the mix.

• Never mix more than one week’s supply of made-up teatspray at one time.

• Use well designed teatspraying equipment to aid good application.

• Ensure you and your staff spray the complete teat area. The front quarter is regularly the one that is missed and in trials is the most common quarter to have mastitis.

Teat condition

Bacteria control on teats has a lot to do with the teat condition. If your cows’ teats are in good condition then there are no nooks and cracks for the bacteria to hide in and evade contact with the teatspray.

The addition of emollient at the right levels, especially in the spring, will enhance teat condition right from when a cow starts being milked. You should aim for at least 17% emollient level in the mix until calving has finished. The emollient also adds a cling factor to the teatspray which enables it to form a drip over the teat end, sealing the teat canal until it closes naturally after milking.

Tips to help control the spread of mastitis and manage bulk somatic cell counts

• Use dry cow treatment on the last day of milking.

• Always have a machine test done at least once a year.

• Teatspray after every milking.

• Teatspray as soon after the cups come off as practical.

• Use an appropriate amount of glycerine in your spring teatspray mix. Teat condition is paramount.

• Run a separate mastitis herd and always milk these last.

• Avoid using test buckets if you can because the chance of cross infection to the next cow is far greater using test buckets or quarter milkers.

• Always strip all four quarters to make sure a cow is free from mastitis before she goes in the milking herd.

• Consider foremilk stripping all cows in the milking herd once a week in the first month of lactation.

• If you are stripping cows, keep hands sanitised from one infected cow to the next.

• Only have staff with experience looking for infected cows.

• Have a clearly defined and understandable marking system for infected cows.

• Use the right antibiotic treatment; if you are unsure of the bacteria you are treating, have a sample analysed by your vet.

• Do not under milk or over milk cows.

• Always break vacuum before taking the cups off a cow.

• Change liners at regular intervals – 2500 cow milkings

• Article sourced from

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