I will regularly get calls to investigate cell count issues on farms or mastitis flare-ups at herd level.

Mastitis is a key area to focus on when improving on farm profitability. Mastitis is inflammation of the udder due to bacterial invasion, and subsequent immune response to those bugs being in the udder. This will hugely affect milk quality and production if not controlled.

SCC is a measurement of the inflammatory cells the cow’s immune system sends to fight any bacteria that have entered the udder.

So by recording SCC at herd or more importantly at cow level, this is how we can measure the severity or persistence of the infection.

I would advise that any bulk SCC above 250,000 should be investigated, although recent research would even suggest 200,000 as a cut-off point.

When investigating mastitis issues, having milk records greatly aids in forming a control plan which can track problem cows. It also helps build a control plan around seen patterns.

‘If we don’t measure we can’t manage’. Equally important is to get a culture of infected quarter/cows and find out which bug/bugs are causing the mastitis.

By finding out which bacteria etc. are involved, we can often determine the way the bugs are being spread.

There are classically two types of mastitis: contagious and environmental. Sometimes, however, with the like of strep uberis it can fall into both categories, which can make control more complicated.

1. Contagious mastitis: The bugs that are usually isolated in these cases are staph aureus and strep dysgalactiae. The source of these bugs is in the udder and teats. The common way they are spread is at milking from cow to cow. The mechanism of spread is through machine or milker.

2. Environmental mastitis: This is usually caused by ecoli and some other streps. The source of these bugs is the environment and occurs usually before and after calving. It can be anywhere there is heavy faecal contamination combined with open teats or poor immunity in the cow.

So when controlling mastitis in a herd we should move away from antibiotic therapy as a safety net. With the emergence of more resistant strains of bacteria this is not a sustainable model.

We all know the signs of clinical mastitis but it is often the subclinical ladies that are difficult/impossible to spot that need to be controlled. Like other areas of herd health, there should be a plan, investigation and monitoring around mastitis

So if you’re getting increased SCC and clinical cases you should talk to your vet and/or cell check advisor. They will then formulate a plan such as the below:

1. Milk recordings assess records for problem cow’s patterns etc. Problems with mastitis recording are a great way to implement control plans around problem cows.

2. Sample milk from infected quarters and culture to isolate bacteria or agents causing the mastitis.

3. I find Californian milk test useful as well to pick up sub-clinical cases that can be a reservoir of infection especially during milking. Especially in high SCC cows it can often aid finding the infected quarter/quarters.

4. When you know bacteria etc involved talk to your own vet about the best choice of antibiotic treatment for cases of mastitis.

5. Look at overall cow health ensure nothing else is depressing immunity such as NEB, fluke, viral infections etc

6. Ensure milking machine is serviced twice yearly and liners are changed after every 2000 milkings.

7. Assess milking routine hygiene, gloves, teat health, teat disinfection, cluster flushing and isolating problem cows. Make sure treatment techniques are appropriate. When dealing with contagious mastitis I advise teat dipping instead of spraying. Ensuring teat dip contacts and covers each teat and is changed regularly. Anyone serious about milk quality on their farm should be wearing gloves and post teat dipping at a minimum.

8. Look at the environment where cows are lying or check for exposure to risks at housing. Clean beds are essential for good dry cow management.

9. Record cases of mastitis and treatments to ensure good plan can be developed and review treatment failures or repeat offenders.

10. Under careful scrutiny consider culling chronic cases or drying off problem cows or quarters.

11. Minimise any stress around milking especially with heifers training them to the parlour before they calve can be a great help.

12. Before drying off you can select 4-5 problem cows or do a bulk tank PCR test to isolate agents active in your herd. Then on veterinary advice select your appropriate dry cow antibiotic tube.

13. Dry off cows and use blanket dry cow therapy or selective therapy depending on advice. The use of a teat sealer +/- a dry cow tube is best practice.

14. The aim of every farm should be for selective dry cow therapy treating only problem cows in the herd based on records of high SCC or clinical case in the lactation. So for example in 100 cow herd last year we treated 18 cows with antibiotic dry cow tube and put sealers in them and only sealer for the other 82 cows.

15. Carefully plan your dry period min 6 weeks ideally should be 8 weeks and when using dry cow therapy carefully take note of withdrawl periods or minimum dry period in days for selected product. I think when SCC or mastitis cases are becoming an issue the only way to control is by a proactive approach. Formulate a plan for your farm and monitor it regularly with your vet.