The California mastitis test (CMT) potentially has an important role to play when it comes to controlling cell counts on your farm this spring.
In many spring-calving herds, the first cows should start calving within the next couple of weeks.
The managing or control of cell counts begins once cows have calved, or even when they are dried-off.
During the dry period, you are aiming to cure any cows that have had cell count issues, and prevent those that haven’t from developing them.
CMT
Ideally, all cows should be CMT before their milk enters the bulk tank. This can help to identify cows that didn’t cure over the dry period, or that picked up an infection.
A CMT is a quick and effective way of monitoring cows, and offers real-time information on the cows.
The procedure for using the CMT kit is very simple:
- Draw and discard the first three draws and then fill each well with a quantity of milk. Try to avoid cross contamination;
- Once all four wells have a quantity of milk, tilt the tray to a 45º angle – this will ensure there is an equal volume of milk in all four wells;
- Turn the tray back flat and squeeze the bottle until an equal quantity is applied to all four wells; there should be an approx. 50:50 mix of milk and reagent;
- Stir the tray for 30 seconds and watch for any changes to the consistency of the solution. The degree of thickness reflects how high the SCC level is within the quarter.
The test should be carried out prior to attaching clusters.
Milk recording
Once enough cows have calved, the first milk recording of the year should be completed. Doing so will provide you with data and make it easier to compare this years data to last years.
You should be looking at your cows based on two brackets during the early stages of lactation, those who had an issue before drying and those that did not.
For the cows that had a cell count issue prior to drying-off, the treatment over the dry period has not worked, and it may be time to start considering moving some of these cows out of the herd.
For those that have developed an issue during the dry period, you need to try and determine what was at fault.
It may have been the drying-off process, the management of cubicle shed/beds or another issue.
Once the cows with cell count issues have been identified from your milk recording data, the CMT also has a role to play in identifying quarters that are at fault – some cell count issues can be down to only one quarter.