Robotic Milking: Are we there yet?

Dr. Normand St-Pierre, Dairy Management Specialist, Ohio State University

Imagine this: you get up in the morning and the cows are already milked. In fact, the cows milked themselves and they routinely do this three times a day. You no longer have to deal with kicking a lazy teenager out of bed or a hired hand who doesn't show up. This sounds good, doesn't it? In essence, this is what robotic milking was supposed to be. The reality has been somewhat different. A certain proportion of cows do not adapt well to robotic milking. There are still issues related to mammary health and increased somatic cell counts. The economics of robotic milking is largely dependent on numerous assumptions. In general, robotic milkers are not competitive with conventional systems in the US. Many of these issues will be resolved with time. Likewise, we expect to see a decline in the price of milking robots due to increased competition among manufacturers, larger production volumes, and more efficient manufacturing. During our last Ohio Dairy Management Conference in December 2002, Mr. Jack Rodenburg of the Ontario Ministry of Agriculture and Food presented an excellent summary of the Canadian experience with robotic milkers. For those who want to read more about it, you can either order your own copy of the proceedings ($15/copy) by contacting Mrs. Amanda Hargett ( or by downloading the following document from our website (Robotic Milkers: What, Where, and How Much?).

But, why don't we see more milking robots in the United States? It is simply because all Grade A milk produced in the US must meet the requirements stipulated by the Pasteurized Milk Ordinance (PMO). The PMO is written by the Food and Drug Administration (FDA) and it sets the minimum standards to be implemented by regulators in each individual state. Readers with an interest in the details of the PMO can consult the latest version of the document at: Within the PMO is a list of guidelines regarding manufacturing equipment for the harvest and transport of raw milk. These are called the 3-A standards. These set the minimum standards to be met by all milking equipments, including of course, the milking function of robotic milkers. Currently, robotic milkers face five challenges from the PMO regulations:

1. Inspection of fore-milk,
2. Detection of abnormalities,
3. Diversion of unacceptable milk,
4. Proper and effective preparation of teats prior to attachment, and
5. Separation of the milking area from the animal housing area.

The first three items raise considerable technical and regulatory difficulties. On the technical side, the automatic screening of milk needs to be done very rapidly under a robotic system. More importantly, engineers must be provided with a clear physical definition of what is normal and what is abnormal milk. Definitions that were sufficient under a conventional milking system where decisions are made by a human being are no longer adequate under automation. It is expected that the FDA will issue a new statement regarding the definition of normal and abnormal milk in July 2004. This should clear the way for state regulators to apply the PMO to robotic milkers.

Regarding the effective preparation of teats prior to attachment (item 4), the PMO requires that teats must be completely dry prior to the attachment of the milking unit. Of course, this is not actually met in the strictest sense of the word "dry" in most milking parlors, and it is not met at all by any of the current robotic systems. New interpretations of the word "dry" will have to be issued for robots to meet the PMO.

Lastly, the PMO requires a physical separation between the free stall area and the milking center to prevent the introduction of unacceptable odors and air contaminants into the system. Many of the designs associated with robotic milkers are challenging the interpretation of the term physical barrier. There again, regulators are forced to re-think or clarify their definitions.