With an industry-wide effort underway to reduce the amount of antimicrobials used on-farm, routine milk sampling can aid decision making when it comes to selecting the most effective mastitis control interventions.
Getting the most from results, however, requires attention to detail when it comes to gathering samples, but also in terms of going through results regularly alongside the vet.
Suggesting a target of fewer than 30 cases per 100 cows per year, Nantwich farm vet Joe Mitchell says decreasing long-term mastitis prevalence on-farm comes down to building a picture of what is causing an outbreak.
He says: “Going through milk sample results data regularly with your vet can help indicate the root cause of a problem and combining that with mastitis data can help identify whether a strain is environmental or contagious or if cases are spiking during the dry period or when cows are in-milk.
“Once we know what pathogens are on-farm, we know where to focus our attention and can be more specific in terms of formulating an effective treatment plan to make sure interventions can be correctly targeted and, therefore, more likely to be successful.”
Scrupulous hygiene when collecting samples, however, is absolutely crucial to getting accurate results, which should be done using sterile sample pots.
He says: “It is crucial no contamination is getting into samples. A contaminated plate is frustrating as it completely confuses results and makes the test a waste of time and money.
"This prolongs the process in waiting for the next opportunity to gather samples which does not help in getting on top of an outbreak.”
How to collect a sterile milk sample
1 Wear clean gloves
2 Clean teats and udder with warm water and dry wipe, ensuring any bits of dirt are removed
3 Pre-dip and leave on for 30 seconds then wipe off
4 Clean the teat with surgical spirit
5 Strip out five or six draws of milk and discard
6 Surgical spirit the end of the teat again, open the sample pot and milk in three or four draws before closing the lid straight away, keeping the lid off for as little time as possible