Any farmer who has dealt with a high somatic cell count problem will tell you how frustrating and depressing it can be. SCC problems are most often related to human error, so we must look at the human roles first before blaming the machine or good old stray voltage.

It is important to go through a consistent routine when assessing each area. I’ll go through the steps I assess when getting to the bottom of SCC problems.

High SCC means a proportion of the herd has inflammation in their udders. This is often caused by bacteria, with some being down to stress also. We need to chase the infected cows and even go after the infected quarters. We must decide if they can be treated or dried off to minimise the spread of infections.

Then we need to look at the reasons why SCC problems might be occurring and this requires a systematic approach.

In a high SCC herd we must:

  • Identify the infected cows/teats as quickly as possible with CMT or milk recording.
  • Stop the spread of these infections by having consistent, clean milking routines.
  • Then look at any risks or bottlenecks that have contributed to the problem and eliminate them.
  • The machine and the milker can both spread infection from udder to udder

    13 steps to controlling SCC in dairy herds

    1 Examine the premilking routine

    Is there a lag phase between preparation and attachment to allow milk letdown, or is it too long, with one person trying to milk too many cows together? The optimum lag phase is about 60-90 seconds from entry stimulation of teats to putting the cups on. Look to see are clusters attached to clean dry udders.

    2 Check each quarter

    Is forestripping done to identify any problem cows or pick up mastitis early? Does forestripping suit your routine even though its a legal requirement?

    3 Look at how well clusters are attached,

    The target is to have <5 % of clusters attached incorrectly, although ideally zero.

    4 Checking for over- or under-milking in cows

    With overmilking, you may see some teat end damage. With undermilking, you will often see clusters falling off early. A great place to watch is the glass bowl underneath the cluster before they come off.

    5 Check milker hygiene and give it a rating

    The most likely source of subclinical infections is the milker or the machine.

    6 Score the milking pit hygiene

    Look for cleanliness and the availability of clean towels etc.

    7 Correct post teat dipping

    This is an essential part of SCC control. I look at the three Vs when critically assessing how well teat dipping is being done on farm. The active ingredient for post-teat dips can vary, but the important rules to get right are:

  • Volume: the correct amount of teat dip is being used at each milking for spraying. This is 15ml per cow per milking and for dipping this is 10ml/cow/milking.
  • Viscosity: the right thickness or viscosity is really important when picking a post-teat dip. This may vary at times of the year, for example outdoors versus housed. Match the teat dip to the challenge.
  • Visual: it is really important to look and see if the whole teat is being covered with dip or spray.
  • 8 What is being done during milking with high-SCC cows?

    Firstly are high cell count cows being identified and are they being milked last or managed appropriately? Are they being removed from the herd if they are a persistent source of infection? Are clusters being washed after problem cows (this must be done correctly if being practised)?

    9 Is milk recording being done on farm?

    Without this, it is nearly impossible to manage SCC issues in a dairy herd. If milk recording is being done, are farmers using the information correctly?

    10 Look at the culling policy of the herd

    Particularly focus on culling around chronic mastitis cases. Are certain high cell count cows being kept that are repeat offenders? Is a high culling percentage masking underlying problems elsewhere in the milking routine

    11 Check the machine

    Do a full MOT on the milking machine checking the vitals such as vacuum (47-50PKPH), vacuum reserve and liners. How regularly are liners being changed and also is the machine being serviced annually by a trained technician.

    Remove one to three clusters in a parlour and check vacuum reserve during milking.

    Stray voltage is often blamed for SCC problems. A simple trick for assessing stray voltage is walk the farm dog through the parlour when the machine is on. They, like cows, are very sensitive to voltage and will let you know if there are issues.

    The machine can play a role in SCC issues but too often is the first port of call for every problem. Just as we service our cars and tractors, the milking machine deserves at least an annual MOT. It is the machine making you the most money on your dairy farm.

    12 How are clinical cases being spotted and treated?

    What medicines are being used to treat the infections and what response to treatment are we getting on farm?

    Record clinical cases and also look at cows with high SCCs to see what treatment they have received. Cows not responding to treatment indicate poor drug selection, resistance problems or treatment failures due to infections with staph aureus.

    This information must feed into a control plan and also feed into building a proper treatment regime, drying off infected quarters and good culling decisions.

    13 Drying off protocols

    These are also a very good place to focus in on when assessing an SCC control plan or problem in a dairy farm. What tubes are being used and why are they being selected? Are cultures being done of problems cows and quarters? You can take and freeze a sample if you want to send four to five samples together for testing.

    What is the drying off procedure like on the farm. Talk through procedures, numbers and the use of sealers. Look at milk recordings either side of drying off and critically assess cure rates. This will give you an indication of how well drying off protocols are working on the farm.

    When dry cow antibiotic tubes are being used, are they being matched to the challenge effectively?

    This is the systematic approach I take to investigating a SCC problem in a herd. Often many things have been blamed, such as stray voltage. I’m often asked what the best tube for a high cell count cow is, which is the wrong approach to the problem. You will never treat or cull your way out of a SCC problem. Well, maybe in the short-term you will, but the long-term solution to a very costly problem is a step-by-step approach.

    Implementing effective procedures around milking will pay back farmers. To effect change can be difficult and requires the right mindset, so maybe mastitis control is about having the right mindset.