Farm Ireland

Wednesday 21 March 2018

Controlling mastitis is vital from first calving

John Donworth

Last year I met dairy farmers who had to dry off dairy cows in September. They did this purely to keep the overall geometric SCC of the dairy herd under the magical 400,000 level.

For one reason or another, SCC levels in these herds had got totally out of control during last year. And it wasn't as if any of these farmers had changed their management practices during that year. The problem took on a life of its own and was made worse by the stress placed on cows as a result of the bad weather.

Controlling mastitis is a costly business. Dr Finola McCoy, who deals with the Euro Milk Project, has calculated that the average cost of dealing with mastitis issues among her 23 farmers is €30,000.

Mastitis is a serious cost issue on Irish dairy farms and, right from the time the first cow calved this year, we need to be on top of this one.


The first critical period for infection-spread the cow has to deal with is in the two-week period before she calves down. Her udder is beginning to fill with milk as she approaches calving. This puts pressure on the udder and the cow may even begin to leak milk in the immediate pre-calving period.

This is a real danger period as the possibility of dirt and infection gaining entry through the teat canal is increased. If infection gets in here the possibility of the cow calving down with clinical mastitis is increased. And when this happens, the possibility of that cow infecting five to six of her comrades in the milking parlour also rises.

The target for clinical cases of mastitis in the first month of lactation is five for every 100 cows. This is a difficult target to achieve, but it sets the bench mark.

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Cleaning cubicle beds, in the two to three weeks before calving, is essential. Cubicle beds should be scraped down twice a day. The back two-thirds of the cubicle beds should get a shake of lime to help with keeping the bed dry.

Of course, all this work will be a waste of time if the cubicle passageways are not also kept clean. Cows will take dirt up onto the cubicle beds if they are walking in dirty cubicle passageways. Where scrapers are in place, they should run at least six times a day, and maybe even eight.

What about hygiene in the calving boxes? Again, a critical area. The cow is maybe in here for two days and if there is a build-up of dung in this area then the challenge to the cow's udder is immediately increased. Calving boxes should be cleaned out and disinfected on a regular basis.

What happens when the cow reaches the milking parlour? She should be milked by a machine that was tested before the first cow calved. She should also be milked by a cluster that has a new set of liners.


Early identification of cows with elevated cell counts is critical in the fight against mastitis and, while the cow with clinical mastitis will clearly identify herself, her comrade with no clinical mastitis but with an elevated cell count will be much more difficult to detect.

Before the cluster is put up on any cow, a squirt of milk should first be squeezed from each teat. This milk should be checked for the presence of clots and, if any are found, the next step should be to get out the Californian Mastitis Test (CMT) kit. The kit can be bought in all co-op hardware stores. If the CMT shows up a quarter that has an elevated cell count then you are in new territory. This quarter, for one reason or another, has picked up a new infection and you have to do your best to confine it to the one cow.

This cow must now be dipped before milking with a non-iodine-based teat dip. She must then be dried with a paper towel. When the cluster is taken off her it must be dipped in a five-litre bucket of water to which a food-grade disinfectant (paracetic acid) has been added.

This is all extra work, but it is critical because this cow is capable of infecting the next six to eight cows that the cluster is put up on. This is due to the millions of bacteria that are present due to the infection. You must break the infection link. By doing this you are protecting the uninfected cows from the infected ones.

As regards milk records, these should be completed by March. This will do two things for us. Firstly, it will identify cows with elevated cell counts that we have missed and secondly, it will tell us how successful our dry cow therapy was in reducing the elevated levels of SCC.

Irish Independent