An automatic milking system (AMS) allows a lot of individual information about each cow to be recorded and stored.

Using the electronic information, the farmer can track each cow’s movement through the paddocks. The amount of milk being produced by each cow (and even each teat!) can also be recorded.

Monitoring milk quality

Sensors or electronic measuring devices can be used to record the amounts of specific substances in the milk, providing extra information on the milk quality and/or health of individual cows.

Examples of substances that farmers might want to measure include antibiotics (so that the milk can be separated from the rest of the batch), somatic cell count (which might indicate the presence of infections like mastitis), milk solids (an indication of milk quality) or specific high-value substances like lactoferrin.

The AMS also allows farmers to easily separate the milk of certain cows from the milk of other cows. This is useful if a cow is producing colostrum or if she is being treated with antibiotics. The range of data collected is huge, and careful monitoring enables the farmer to manage the herd more efficiently.


Continuous milking is ideal

In New Zealand, the whole herd is usually batch milked twice a day. In contrast, a robotic milking machine can only milk one cow at a time, but the milking process can be carried out continuously. The system is most efficient if cows are milked throughout the day and night. In an ideal situation, a steady stream of cows will arrive at the machines over the whole 24-hour period.

Experience at the Greenfield Project has shown that the actual flow of cows into the dairy is not continuous, and there is a very quiet period during the early hours of the morning. To gain the maximum economic benefits from the robotic technology, the challenge is to develop farm systems that can maximise the period of time the machines are in use.

Cow characteristics important for automatic milking

The Greenfield herd is 85% Friesian, and the remainder are Jerseys, Ayrshires and crossbreeds. At the moment, it does not look like one breed is better than another for an AMS, but it is important that the cows have suitable udders (occasionally the milking robot does not seem to attach very easily to a particular cow), are intelligent and can learn to use the system quickly.

Future research focus

The Greenfield farm is a model for totally automated dairy farming in New Zealand and is now expected to run economically. Future research will focus on making AMSs more financially rewarding by improving cow training methods and increasing AMS utilisation. There is also the challenge of applying AMSs to the range of physical environments that make up New Zealand’s dairy farms.

Other work is being carried out to test the potential for using an AMS to separate specific components in the milk as it comes out of the milking machine. This technology could be used, for example, to separate specific proteins that are of high value but low concentration in the milk, such as lactoferrin.

In the future, it may be possible to actually separate out these high-value components right there on the farm, instead of pooling all the milk together and sending it off to a big dairy factory to be processed.

Published 15 October 2012