Traditional milk bacteriology is slow because the samples have to be sent away from the farm. It may also be costly. As a result, treatment of mastitis cases is undertaken with a drug that is “best guess”. This could be based on past culture results or farmer experience. The full course of treatment takes 3-5 days, and is “all over” by the time the culture result is back.
The incorrect choice of drug could result in a failure to cure. This in turn could lead to longstanding chronic infection of the udder, which becomes difficult to cure. In this state, the cow may shed bacteria, putting her herdmates at risk of infection. She will also produce milk which is unacceptable for human consumption and may contaminate the herd vat. If she becomes an incurable case, she may have to be culled, despite being an otherwise productive cow.
Sometimes the farmer is not certain whether to treat or not, as many cases may be in a process of “self cure”. This is particularly true in apparently mild cases. Testing with the Overnighter may result in not having to treat the cow, and avoid costs of treatment, milk discard, risk of antibiotic contamination of the milk and the hassle of running the cow separately from the herd.
Farmers are not in the habit of collecting milk samples before treatment, and therefore much potentially valuable information is lost. The advent of freezing to perform retrospective culture has helped to retrieve some of the information. Samples can be frozen and analysed in batches at a later date
Finally, a farmer may start treatment of a cow, then when the treatment fails, attempt to culture the “difficult” bug. Unfortunately, the exercise is normally unrewarding, as treatment has decreased the bacterial count sufficiently that routine culture will not pick up the infection. The result is frequently a frustrating “false negative”. Routinely culturing with the Overnighter before treatment of every cow can help avoid this scenario.
The Solution
The Overnighter is a much more user-friendly milk culture technology than is currently available. Because it is relatively rapid and cheap, more testing can be done in a timely way, which has a profound influence on drug prescription and use.
Milk culture can also help in herd management troubleshooting, as the type of bacteria grown can point to certain factors (such as milking machines) being major players in the development of the herd problem. Thus milk culture results for a herd can be critical to solving problems and preventing mastitis in the future.
