Preventing mastitis is no easy task due to the many risk factors that can be present on any given dairy. The variation in the biology of the cow, the bugs and the humans performing the tasks can make it very difficult to control on any given day. One risk factor, though, that should be easier to manage is the function of the milking equipment.
Mechanical equipment is more predictable and should be simpler to set appropriately and monitor over time. Based on the farms I visit, though, there remains a large opportunity for improvement with the management and monitoring of the milking system in four areas:
- Vacuum and pulsation settings
- Automatic take-off settings
- Rapid detection of malfunctioning equipment
- Unit alignment
Vacuum and pulsation settings
Each farm needs the claw vacuum and pulsation set appropriately for the equipment they have installed and the goals of the dairy. Since this affects every cow milked, it is critical we get it right but, surprisingly, there are some dairies where no one has performed the appropriate testing to determine the levels.
If you do not know the average claw vacuum at peak milk flow for your dairy, ask your equipment dealer. If they do not know the value, ask them to measure it so an informed decision can be made. The pulsation settings are also critical and should be rechecked and re-evaluated if a different liner or shell is installed.
Automatic take-off settings
Automatic take-off settings are another area that needs to be set appropriately for the equipment and goals of the dairy and then monitored and adjusted as changes are made. Different manufacturers have different names and recommendations for the different parameters, but it is worth the effort to know the adjustments for your system and what they mean.
The two parameters we see set inappropriately most often are the take-off limit at the end of milking (which may include an additional delay time) and the vacuum decay time.
On a recent herd visit for an environmental mastitis problem, it was discovered the majority of the units were hitting the deck before retraction at the end of milking. This was leading to major manure contamination of the shells and the mouthpiece of the liners, which increased the likelihood manure ended up at the open teat end.
After questioning the owner further, this situation had been going on for at least six months after a change to a different liner style. A simple change in the vacuum decay setting corrected the issue at the next milking.
Rapid detection of malfunctioning equipment
Scheduled maintenance of your milking equipment is required to increase the chances of preventing predictable problems. Although some dairies are able to achieve this with their own personnel, it may be more reliable to have your equipment dealer perform this work on a predetermined schedule. This should be viewed as an insurance policy that brings the benefit of a trained set of outside eyes to your farm.
However, some component of your milking equipment will occasionally fail, and having a system in place to detect and correct this as quickly as possible is critical to minimizing the number of cows you put at risk.
For some dairies, this is as simple as a handwritten log book where milkers record any issue with milking equipment they detect. There is a dedicated person from management who reviews this log on a daily basis and is responsible for initiating the appropriate fix in a reasonable time frame.
On other dairies, someone from management reviews the daily error reports from the milking center software and signs a copy of this report, letting others know it has been handled. Having a lead milker perform a pre-milking checklist before each milking will help limit the number of cows put at risk due to improperly performing milking equipment. This checklist would include:
- Record system vacuum in a log book
- Check that liners are pulsating and properly aligned in the shell
- Open all claw and liner vents with an appropriate tool
- Check for any torn hoses, gaskets, etc.
- Listen for any air leaks in the system
Making sure your milkers have easy access to replacement parts and they are trained in how to install them will also go a long way to quickly correct simple issues, such as a torn liner or a hole in a short air tube.
Unit alignment
Unit alignment is another area to monitor and manage to achieve top performance from your cows. Unit alignment can have a significant influence on the milking speed of an individual quarter and can therefore influence unit-on time and potentially the time spent in low flow of the other three quarters, which milk out at normal speed.
This increases the risk for teat damage and liner slips on these three teats which spend a considerable time in low flow.
Additionally, many cows will experience discomfort in this situation and start to kick at the unit, which potentially leads to additional liner slips, forced unit removal and increased contamination with dirt and manure of the claw and shells.
Poor unit alignment can also significantly influence parlor efficiency by increasing unit-on time and increasing the number of reattached units.
Unit alignment can be a system problem with improper design of the parlor or of the unit alignment devices. It can also be a maintenance issue with the unit alignment devices in poor repair or non-functional.
This needs to be evaluated for each milking center, as there is no one system that works for all. Any reasonable options to promote better unit alignment of the whole system should be explored.
Unit alignment can also be an individual milker issue and therefore needs to be part of a monitoring program for milkers. If milkers are not properly aligning units, they need to be retrained and reassessed. The small amount of time milkers need to spend properly aligning units can pay large dividends in increasing parlor efficiency and reducing the risk for mastitis.
I encourage you and your equipment dealer to take the time to evaluate your milking system in the four areas outlined above to determine if there are opportunity areas you are not capturing. Some of these corrections are relatively simple to implement but can have a large and ongoing impact in reducing the risk factors for mastitis and improving the milk quality of your farm. 
Paul Virkler is with quality milk production services with the College of Veterinary Medicine - Cornell University. Email Paul Virkler.
