Targeted approach for selective dry cow management decision making

Selective dry cow therapy (SDCT) aims to reduce broad spectrum antibiotic therapy by targeting only cows with an intra-mammary infection with antibiotics and those with a healthy udder sealant only. This has in the past been reliant on monthly milk recordings and individual Somatic Cell Count (SCC), mastitis records, and using the California Mastitis Test (CMT) test on the day of drying off. CMT test is subjective to interpretation and not always carried out to the specifications and the milk recording SCC is an average of the four quarters and could be up to a month out of date.      

In this project three farmers in north east Wales, milking a total of 1,700 Holstein Friesian cows, investigated the use of milk leukocyte differential (MLD) testing using Q Scout Farm Lab. Q Scout is a new and scientifically proven portable diagnostic machine that scans milk samples microscopically. It allows for the sampling and testing of each milking quarter prior to drying off to determine whether individual quarters require antibiotic therapy to combat an intra-mammary infection, or whether they could be dried off using an internal teat sealant in isolation. The test results are available in a very quick turnaround, meaning that dairy managers have access to current udder health data allowing them to be confident in their decision making for every cow and every individual milking quarter.

Project Outcomes

• This new technology, with its very quick turnaround of results gave confidence to the farms that they were drying off their cows correctly.
• Some of the cows tested would not have been treated with antibiotics if farmers were relying on milk record cell count data alone, meaning that they would have calved down with mastitis.
• MLD testing has the potential to aid the reduction of spectrum antibiotic therapy through targeting only the cows with an intra-mammary infection with antibiotics and those with a healthy udder with sealant only.
• As a result of reducing antibiotic usage, the three farms were able to save a total of £7,133.80 during the lifetime of the project based on an average antibiotic tube cost of £2.49.
• MLD is not risk free and correct training for clean administration, record keeping, and using new technology, is required to ensure these risks can be reduced.