Milking Efficacy

To reduce mastitis and maintain milk quality, dairy farmers need to keep milking equipment in good working condition. However, milking efficacy should be measured from two other viewpoints, the amount of time the milking cluster is attached to the udder (unit on time) and the percent of unit on time that milk is flowing at peak. When milk isn’t flowing while the unit is attached, it is not only unproductive, but more importantly, could damage the teat tissue, which could increase the risk of mastitis and decrease milk yield.

Regular Maintenance
A majority of dairy farms have their milking equipment tested to ISO 6690 Requirements and serviced as per manufacturer’s recommendations on an annual or six monthly cycles. Proper equipment function is necessary for milking efficacy. Not alerting and training staff in areas that could lead to poor milking efficacy to routines that don’t achieve consistent milk let down and could cause over milking. Either one of these problems can leave cows “In pain” for a period of time and expose teats to high vacuum levels.

During pre- stimulation before unit placement, nerves carry an electric signal to the cow’s brain. She then releases oxytocin into the blood and then to the udder. It takes about 1 to 2 minutes for oxytocin levels to increase in blood to optimally contract muscle cells around the milk ducts, which then squeeze the milk down toward the teats. The two important points about this oxytocin release are enough teat stimulation (at least 10 seconds of actual physical touching) and the duration of the lag time, that is, the time interval between when teats are first stimulated until the cluster is attached. Regrettably, with increasing herd size, the number of cows that can be milked through the parlour per hour is often recognised as more important. So common talk among dairy farmers is speed of throughput

Measure Milk Flow
How would you know if this is happening in your herd? A milking time test (dynamic test) will show up milk flow from the cluster and vacuum levels during unit on time.

Biphasic milking “under milking “

“Milking is so routine, we don’t even think about it. It just happens,”
The end goal for udder preparation before milking is to maintain a constant routine at each milking:

1. A minimum of 10 seconds of physical stimulation on teats.
2. A lag time of 60 to 90 seconds before units are attached.
3. A parlour routine that consistently accomplishes 1 and 2 from the beginning to the end of milking
4. When there is a high vacuum but little milk flow. This can happen any time before complete milk let-down, the cow lets milk down which appears to be complete milking, then stops for 15 – 30 seconds.

So why stimulate the teats? How important is lag time before unit attachment?
In a recent study of farms, a large percentage experienced biphasic milking “under milking “in more than 30 percent of the cows. Biphasic milking results when oxytocin has not reached the mammary cells at the time the unit is attached. In other words, it is a delayed start of peak milk flow. The goal in the modern milking parlour routine is to have less than 10 percent of cows experience biphasic milking” under milking “.

With biphasic milking, milk flow starts as it originates from the teat and gland cisterns, but then stops or slows considerably because milk let-down has not been activated. Milk flow may be stopped for 30 seconds or more until sufficient stimulation, or sufficient time allows the arrival of oxytocin that causes the milk flow to begin again.

The impacts from biphasic milking “ under milking “ can be uncomfortable to cows, and could result in congestion in the teat, high vacuum without milk flow can cause stress on the teat . Under milking can cause teat end roughness, and it has the potential to reduce milk yield.

Milk let down is now considered as important as over milking exposing the teat to full vacuum has extreme effect on the cows teat end .
As herd numbers increase in the UK it is more important to train staff and new employees to a constant routine without cutting corners.