Key Performance Indicators ( Somatic Cell Counts)

This is the third in a series of articles based on Key Performance Indicators (KPI) for Guernsey herds. This time we are looking at Somatic Cell Counts and how high cell counts and chronic offenders in the herd can affect the bottom line.

It has not been the best of years for low cell counts! The October DairyCo bulletin stated that the latest GB Somatic Cell Count (SCC) figures averaged 203,000/ml in August 2012. This was 8,000/ml (4.1%) more than July and was the highest figure since September 2009.

Wet weather, damp straw, mud, cows in one day and out the next do not aid us in trying to keep the bugs at bay. It has, shall we say, been challenging in trying to keep cell counts down.

For a lot of producers any bulk SCC count over 200,000 will probably be costing at the very least 0.5ppl and for some, a premier bonus payment as well. In addition there is the hidden cost that comes with sub-clinical mastitis of reduced milk production and also the spread from infected cows to healthy cows.

The KPI study undertaken by Dr James Hanks & Dr Mohamad Kossaibati in April 2011 shows that of the 33 Guernsey herds in the group, only 15 averaged a SCC of less than 200’000ml over the year.

What can you do?

First, look at the SCC contribution report that you get every month when you milk record. Look closely at the cows that are over 200,000. Check cows that have calved in the last month, were they dried off with a high cell count? If so perhaps the dry cow tube policy needs looking at. If the SCC was low at the end of the last lactation and is now high then California milk test (CMT) at the next opportunity to identify quarters with sub-clinical mastitis. Once you’ve identified the quarter then take a milk sample and send it to a lab to identify the pathogen. Once you know what you’re dealing with you can develop, with your vet, a strategy to deal with it. For late lactation animals with high SCC it might be beneficial to dry them off a bit earlier than normal to give the udder a long rest.

Any cow that is over 500,000, and is persistently in that category month after month should be considered for culling if all other treatments have failed.

Herds that have registered with the EGCS for Interherd+ reports should have received them via email. If you have not registered but would like to receive these reports – which are free – then please contact Caroline Cox for a form.

The reports this quarter will focus on SCC and help you to clearly identify animals that have high cell counts. Below is an example of one of the tables in the report.

SCC contribution 27/09/2012

Your cows with SCCs over 500,000 cells and their contribution to the overall SCC contents of the bulk tank.
Note the Type. How many are long-standing chronic cows?

The report above shows the high cell count cows in the herd at the last recording, cow number 410 has a SCC of 4,034, which accounts for 28.6% of the bulk milk SCC. As you can see, if this cows milk is removed, then the bulk milk sample would drop from 140 to 101. As the top two cows on the report are long standing chronic offenders, cow 411 having had mastitis twice in the previous lactation, it would make sense to cull both of these animals.

Cow 791 is a first offender, CMT all the quarters, identify problem quarter and send milk sample away to identify the pathogen. Once the pathogen is identified then treat with a suitable antibiotic.

Cows 787 and 321 are both approaching drying off so would probably benefit from a longer dry period to rest and hopefully cure the problem.

If you are trying to reduce your SCC then hopefully these reports will help you clearly identify the culprits and allow you to formulate a plan of action.