As we are now into the thick of autumn calving, it’s important to be considerate of keeping your somatic cell count (SCC) down, as it easy to let it slip when cows are calving down.
Any increase in SCC above 100,000 cells/ml is associated with a reduction in animal performance and will have a significant impact on milk receipts.
The periods of greatest risk for infection to develop are at drying off; two to three weeks post dry off; two to three weeks pre-calving and the first month post-calving.
With the further uptake in selective dry cow therapy (SDCT), rather than blanket drying off, SCC can be harder to manage if the sealer was not administered properly or selection of the cow was wrong.
This along with a few other factors has caused the SCC nationally to creep up ever so slightly, as only around 60% of the herds nationally have been under the 200,000 cells/ml in recent years.
The drying off of cows is critical to the future quality milk production of the cow for the following lactation, however, as all autumn calvers are calving down at the minute, the focus should be on minimising the risk prior to calving and post-calving.
Autumn calving
The biggest risk factor at this time of the year for the autumn calving herd, is the management of calving boxes and cubicles as cows calve down.
The freshly calved cow is going to need to have access to clean dry cubicles that are brushed and limed twice daily, as well as regular cleaning of calving boxes to minimise the risk of infection occurring.
The protocol at milking is always key to minimising SCC and mastitis, but, in particular, in the early post-calving period where the risk is highest.
The following protocol should be taken for the freshly calved cow:
- Milk separately from main herd;
- Thoroughly wash and disinfect/change gloves before and after handling the cows;
- A pre-spray of disinfection is advisable;
- Inspect foremilk;
- A California milk test (CMT) on the freshly-calved cows at the last milking before joining the main herd.
By carrying out a CMT, you will be able to identify any mastitis infections and reduce the risk of it spreading to other cows in the herd.
In recent years, staphlococcus aureus has been the main source of infection in herds and it is a highly contagious infectious agent that needs to be controlled on Irish dairy farms.
The prevention of infection in your herd of cows is driven by excellent parlour management, such as ensuring the cows are clean when being milked and using the correct post milking teat disinfection of roughly 15ml/cow/milking, ensuring full teat coverage.
Infected cows whether they have clinical or subclinical mastitis need to be segregated from the herd or their cluster must be thoroughly disinfected post milking.
All clinical cases should be recorded to allow for case histories to be created to help identify any problem cows in the herd that might go undetected.
Limiting SCC and mastitis with heifers
First calvers in late lactation and in-calf heifers are also prone to picking mastitis infection and the perception that young heifers coming into the herd will reduce your SCC problems is not necessarily true.
To try and limit this issue at heifer level, combatting the issue with in-calf heifers prior to calving needs to be done as follows:
- Make sure the heifers have adequate space at housing, one cubicle space per heifer;
- Make sure cubicles are brushed and limed twice daily in the weeks approaching calving;
- Ensure that the heifers receive cubicle training either as yearling or in the winter prior to calving;
- Parlour train the heifers and teat spray them as they come into the parlour once or twice weekly.
Ensuring that heifers don’t start off their first lactation with high SCC or mastitis infection is crucial for their future production of quality milk and their longevity in the herd.
If all these measure are taken on your farm, it will help your herd achieve SCC levels of less than 100,000 cells/ml during the early lactation, which will set the herd up for low SCC for the whole lactation.
