Paper on the effects of the Dutch mastitis control programme

One of my ideas for this blog is to make an entry including the main results of scientific papers that we have published. Well, I am a little behind schedule. But here is a paper that was published last February. So for some of you, this post does not add much value I am afraid. On the other hand, not everybody is following the scientific literature so who knows it is interesting.

Last year, Theo Lam, projectleader of the Dutch 5-year mastitis control project and director of UGCN (the organization that was instituted just to carry out much of the work within that project) had the idea to write a paper on the changes in udder health in the Netherlands during the 5-year mastitis control project. This paper was published in the Journal of Dairy Science last February. Before the programme started, a "zero-measurement" was done, to see what the udder health status was in the Netherlands, in terms of incidence of clinical mastitis, somatic cell count as well as knowledge and attitude (mindset) of the farmers. Five years later these measurements were repeated. The difference between both measurements can be attributed to the mastitis control programme. Basic conclusions were that the indicence of clinical mastitis decreased significantly with 5.4 %. There was no significant difference in somatic cell counts. Also the mindset of farmers towards udder health did change during the programme time. The data were used for a normative economic study, which showed that, on the national level, the total failure costs (milk production losses, culling, treatment and veterinary costs) due to mastitis decreased with € 8 million per year.

However, this sounds OK, but there is one major problem: there is no control group. We do not know how the status of Dutch dairy farmers would be when the 5-year control programme would not have been there. So we have to be a bit careful when interpreting these figures. The full abstract of this paper is given below.

Because of increasing bulk milk somatic cell counts and continuous clinical mastitis problems in a substantial number of herds, a national mastitis control program was started in 2005 to improve udder health in the Netherlands. The program started with founding the Dutch Udder Health Centre (UGCN), which had the task to coordinate the program. The program consisted of 2 parts: a research part and a knowledge-transfer part, which were integrated as much as possible. The knowledge-transfer part comprised 2 communication strategies: a central and a peripheral approach. The central approach was based on educating farmers using comprehensive science-based and rational argumentation about mastitis prevention and included on-farm study group meetings. Comprehensive education materials were developed for farmers that were internally motivated to improve udder health. In the peripheral approach it was tried to motivate farmers to implement certain management measures using nontechnical arguments. Mass media campaigns were used that focused on one single aspect of mastitis prevention. These communication strategies, as well as an integrated approach between various stakeholders and different scientific disciplines were used to reach as many farmers as possible. It should be noted that, because this intervention took place at a national level, no control group was available, as it would be impossible to isolate farmers from all forms of communication for 5 years. Based on several studies executed during and after the program, however, the results suggest that udder health seemed to have improved on a national level during the course of the program from 2005 to 2010. Within a cohort of dairy herds monitored during the program, the prevalence of subclinical mastitis did not change significantly (23.0 in 2004 vs. 22.2 in 2009). The incidence rate of clinical mastitis, however, decreased significantly, from 33.5 to 28.1 quarter cases per 100 cow years at risk. The most important elements of the farmers' mindset toward mastitis control also changed favorably. The simulated costs of mastitis per farm were reduced compared with a situation in which the mastitis would not have changed, with € 400 per year. When this amount is extrapolated to all Dutch farms, the sector as a whole reduced the total costs of mastitis by € 8 million per year. It is difficult to assign the improved udder health completely to the efforts of the program due to the lack of a control group. Nevertheless, investing € 8 million by the Dutch dairy industry in a 5-yr national mastitis control program likely improved udder health and seemed to pay for itself financially.

Teaching Economics of animal health: what are the needs

You probably know that all teachers think their course and their topic is the most important topic that is taught in an education. Well, it is no different for us people that are teaching Economics of animal health.

On the other hand, we do have an EU-funded network that is aimed at the promotion of the best use of economics by animal health professionals. Within the network, we are working to map existing educational materials and identifying gaps between needs for educational materials and availability of materials. Based on this gap we will develop new materials and make these available for all that want to use it (for more info, see the website of NEAT: www.neat-network.eu). The network was initiated and is lead by prof. Jonathan Rushton, one of the current leaders of the field of Economics of Animal Health.

Last week, the first Annual Meeting of NEAT was held and organized by RVC in London. A little less than 100 people form all over the world attended. Participants were members of the network but also people that were interested in the topic of teaching Economics of animal health. During the meeting, progress was presented but also a number of topics were discussed. I head to lead a discussion on how to close the gap between the Needs of the end user and the materials that are offered by educational institutions. But to answer that, we first have to find out if there is a gap between supply of teaching in Economics of animal health and the demand for teaching. Well, not surprisingly, we concluded that there was a gap. Now for the next step we need to find out what the demands are.

What is the need for teaching in the field of Economics of animal health???

To answer that we have to go out and talk to end-users. And yes, we are going to do that. But we also have our own ideas.

Veterinarians

A first target group of animal health professionals are the veterinarians. A core level of knowledge that all veterinarians should have is the notion that economics are associated with the keeping of animals and with any animal health decision resources are associated (and thus economics). At the farm level this can be costs of intervention (monetary to be paid by the farmer) vs benefits of less disease (expressed in monetary terms). At the companion animal level this can be the costs of the intervention (monetary, to be paid by the owner) vs the utility of a healthy animal (not or very difficult to express in monetary terms). Besides that knowledge on economics of animal health, veterinarians might also want to know about the Business eocnomics of their own practise (how to determine a price, cost price, interpretation of annual economic reports, etc.).

More specifically on animal health the demands for the farm animal veterinary are:

• Being able to reason on the consequences of diseases (including herd dynamics). Go beyond treatment of the individual animal.
• Being able to do economic reasoning, so that veterinarians can (qualitatively) adjust standard calculations (from literature for instance) or to be able to expertly fill in tools that are available
• At the herd level: costs of diseases (problem definition; basics of herd health planning)
• Justify their own fee
• Have knowledge on farmers' behaviour and goals

For companion animial veterinarians a specific demand is:

• Value of insurance (companion animals). Economics behind insurances

Government decision makers

Another group of animal health professionals that might need knowledge on Economics of animal health are people working in governments. Demands for this group of professions are:

• Effect of policies (import/export) on the primary producers (regulatory impact assessment)
• Public vs private goods.
• Assessments on market and sector level (not micro level)
• Farmers behavior (goals)
• Economic background of methods for eradication (how to cope with list A diseases)
• Economics of surveillance
• .....

for this group of professionals as well as for the veterinarians we can conclude that they do not need to receive teaching that they can do their own calculations. It is merely teaching so that these animal health professionals are able to understand calculations and be a informed partner of professionsals in Economics of animal health.

This is just the beginning

The demands given above are just a first idea that was based on discussions during the NEAT annual meeting. If you are reading this blog and think that we forgot something, please let me know (you can comment this blog). If you think that a demand I wrote down is not necessary, let me know also. And finally, if you want to join the NEAT network, feel free to do so. Send an e-mail to : info@neat-network.eu

Why is animal health economics a difficult topic in the veterinary curriculum

Some time ago I posted a blog why I think that it is important that veterinarians know something about economics. Well nothing news here on that.

Fortunately, I am not the only one who thinks so. Last year a European network project started, entitled "Networking to Enhance the use of Economics in Animal education, policy making, and research in Europe and beyond" (NEAT). The objective of this project is to strengthen and enhance the use of economics in animal health in higher education and professional environments throughout Europe. Project leader of this project is Jonathan Rushton from the Royal Veterinary College and one of the key players in the field of animal health economics. There is a blog on the NEAT website and the first contribution on this blog (after the welcome message of the project leader) was my blog on the importance of economics for the veterinarian. As a response, Professor Eystein Skjerve from the Norwegian School of Veterinary Science, made a contribution on the reason why animal health economics is such a difficult topic in the veterinary curriculum. His observations are quite interesting and I have copied them underneath. Have fun!!

The elementary reason for this is of course that economics and production is not among the motivations for applying for vet school. But – there are more fundamental reasons linked to the lack of staff competence in vet schools. Veterinary epidemiologists or herd health staff not properly trained in economics may not be the best starting point, but I assume the major limitations is that staff may not know enough about the economic aspects of the animal production systems. To link epidemiology and economics means that you have to understand the biological rationale of the production systems. My strong belief is that teaching has to start from a clear biological scenario and not abstract economics. A vet student or graduate veterinarian will be able to follow into economy if the biological case is well described.

The challenge is thus to train teachers in economy without losing the intimate connection to animal health and the bio-production systems. Where the “true” economists fit here I forward as a question – should perhaps this be a two-step procedure – that the “true” economists train veterinarians/ epidemiologists at a sufficient level to teach vet students??

Do we recognize our own Veterinary Schools? I have heard stories from older veterinarians in the Netherlands that got economics from an economist. They learned about production functions, consumer demand, cost prices etc. but for me it sounded like the experience that I had with statistics (prof Skjerve is working in the field of epidemiology and statistics). You learn a lot about statistics and at the moment you start doing research you think: "sh*t I thought I paid more attention during those statistics classes!!" I hope I am doing better now. How can we solve this phenomenom? One idea that I thought when we were introducting our elearning courses on animal health economics, is that elearning can be a solution. Just a thought.

2nd North American Precision Dairy Farming Conference

I am about to leave Rochester, Minnesota. A nice city just south of the Twin Cities. On my way here I learned that Rochester is well known because of the Mayo Clinic. In the shuttle from the airport to my hotel, somebody was really surprised that I never had heard of the clinic. This morning I walked through downtown Rochester and it seemd that half of it consisted of the clinic.

Downtown Rochester with in the Middle the Mayo Civic
center where the meeting was held

Anyhow, I was not in Rochester to visit the clinic but to visit the 2nd North American Precision Dairy Farming Conference, organized by the University of Minnesota under leadership of Marcia Endres. The first conference was held three years ago in Toronto, Canada. During that first conference, there wasn't that much good science available yet. This conference showed quite a change: there were plenty of interesting talks. And always surprising to me, there were a large amount of dairy farmers during the conference. I am afraid our Dutch dairy farmers do not go to two-day conferences with lots of scientific knowledge. For us it is interesting, because there were quite a number of farmers panels, explaing what their experience is with certain types of precision dairy farming applications. Good to hear their experiences, but at the same time we have to remember that these were not the average farmers. The organizers had invited an interesting list of renowned keynote speakers: Alex Bach (on feeding management), Jeffrey Bewley (introducting precision dairy farming to us), Albert de Vries (on economics of precision dairy farming), Marcia Endres (on automated calf feeders), Ilan Halachmi (on sensors for disease detection), Margit Bak Jensen (on milk feeding to calves), Ray Nebel (on automated estrus detection), Doug Reinemann (on automated mastitis detection), Jack Rodenburg (on cow traffic in automatic milking), Doyle Waybright (Mason-Dixie farms on farming with automatic milking) and myself (on success factors of precison dairy applications).

Together with Albert de Vries I had the honour to wrap up the conference. It is a bit of a ungrateful honour, because many people are leaving the conference, much of what you want to say has already been told and people just want to go home. On the other hand it is also a nice challenge to make such a talk interesting.

The presentation that I gave can be found here. In short I presented that in my opinion a successful precision dairy farming application (I also call it "sensor system") has to do more than measuring a physiological status in a cow. That data has to be transformed in useful information. Without that information, the sensor is useless. The goal of precision dairy farming applications should be decision support. Sensor information therefore, for some applications, should be combined with other data sources and be associated with decision support tools. There are hardly any applications described in scientific literature (see the review of Niels Rutten) that contain all of these aspects.

Successfull applications should furthermore be economical viable (benefits exceed the costs), although this is not always necessary, for instance in the case of adoption of automatic milking, where quality of life, flexibility of labor etc. are important reasons to invest in automatic milking.

Finally I think that the ultimate goal of precision dairy farming should be to explore the full potential of each individual dairy cow, instead of managing cows in groups. In the old days with small herds, that was possible, with the larger herds, that became difficult, but now with assitance of precision dairy farming technology it is possible again.

Co-operation between farm advisors

Dutch farmers are lucky. Distances are short and every farmer has the availability of many advisors from various sources at a relatively short distance. There is, however, not much co-operation between advisors. I was invited to give a presentation on a "flash-meeting" of the Dutch society for Agricultural Advisors (VAB) on the topic of co-operation between farm advisors. The idea was to give a short presentation and use this as starting point for discussion. Not too many participants were allowed in order to make discussion possible. My presentation was entitled: "Increasing the profitability of herd production programs". The slides are available on slideshare. 

The idea of my presentation was that there are three main groups of advisors on Dutch (dairy) farms: the veterinarian (in herd health programs and occasionally when there are health problems), the feed advisor and the economic advisor. Their knowledge overlaps, vets do know their thing about feed ratios and feed in relation to milk production, while economic advisors have a quite generic knowledge of the dairy farm. Besides knowledge on feed, feed advisors also have a generic knowledge about farming. Sometimes the advisors feel competition from the others, which might prevent co-operation. Moreover, most of the Dutch feed advisors are paid by the feed companies. Their advises are "free" (you pay them with the feed of course), while the other advisors have to be paid per hour. 

I have presented a couple of cases where each of the advisors could, from their point of view, give different advises for the same topic, and these advises might even contradict. 

We quickly agreed that co-operation between advisors is needed in order to improve the profitability of advises. We also agreed that it is the farmer who needs to direct these different advises. However, we are afraid that our dairy farmers are not (yet) good in that task. We do have some data (not published yet, if it is published I will let you know) that shows that in the relation between the dairy farmer and their veterinary advisor all kinds of things go wrong. The vet does overestimate the capabilities of the dairy farmer to ask questions and to take the lead. Well, if we know that that might happen, we should account for it. There might even be a role for one of the team of advisors to coach a farmer in this work. In our opinion, the advising team should meet, under direction of the farmer, to set goals for the coming one or two years. Those goals can be on production level, herd seize, health status, etc. Besides these goals a plan should be made how to reach the goals. The advising team should agree upon these goals and work in their coming individual visits on those goals. The farmer (maybe in co-operation with one advisor who coaches him/her on it) has to keep the team in good place and follow the progress of the plan. 

We were lucky that one of the participants had experience in coaching farmers to take the lead in setting up an advisor team. He was very enthusiastic and has had great successes using this approach. Although not all efforts succeeded, but most did. One example really stood out. This was in the 25 % worst performing farms (economically) and is now in the 25 % best performing farms. Wow, advise can be profitable. 

The challenge is to show this and to make the value of farm advise visual. That is a matter of marketing and we might learn a lot from ordinary business consultants in this. 

Rabies control

I have a PhD student named Ewaldus Wera. He is working at Kupang State Agriculture Polytechnic Univesity in Kupang, West Timor, Indonesia and has a grant from the Indonesian government to get his PhD at Wageningen University. After an initial time in Wageningen to do some courses and to set up his research plans, he went back for data collection. I had the pleasure to visit him in Indonesia. During my visit I had the honour to give a presentation on animal health economics to the veterinary students of Kupang State Agriculture Polytechnic and to visit the Animal Science facilities over there. It was great to find out that there were people there that were following my activities on the social media. Wow.

The most important part of my visit, however, was to make a site visit to the Island of Flores, where Ewaldus is doing is field work, in co-operation with the local animal health authoroties there.

The topic of his research: economics of rabies control. Indeed, a little different topic than most topics I discussin this blog, Nevertheless it is quite interesting. When I had to fly over, I had to make a stopover on Bali and on the airport there was a banner warning for rabies on the island. 

Warning banner as a welcome on the airport of Bali (after 15 hours of flying I was not able to keep my phone steady, so it is a bit fuzzy). 

Basically, rabies is a zoonotic disease that, in humans is always fata once clinical signs appear. The main transmission routes is through dog bites. There is a lot of information to be found on the internet, for instance here and here.

In Flores island alone, rabies is the cause of 19 human deaths per year. After the introduction of rabies, the local government has been taking quite a lot of efforts to eradicate rabies again from the island, without succes until now. Ewaldus has carried out an economic study to evaluate the costs that were associated with the control measures carried out since the year 2000 on Flores island. Currently, rabies control measures on Flores Island include mass vaccination and culling of dogs, laboratory diagnostics of suspected rabid dogs, putting imported dogs in quarantine, and pre- and post-exposure treatment (PET) of humans. 

Using a deterministic economic calculation model, Ewaldus estimated that the control measures were estimated to be US$1.08 million (range: US$0.57–1.42 million) per year. He presented his work at the last ISVEE meeting and the proceedings are available. Interestingly, Ewaldus not only looked at the costs of vaccination, but also at the costs of culling, especially at the value of the culled dogs. In Flores Island, dogs are a source of protein for the population (in other words, dogs are eaten) and dogs play an important role in chasing away monkeys, so that they do not damage the harvest. The consequence of taking those costs into account are that the costs of culling (semi) roaming dogs were the highest portion (about 39 % of the total costs). Post exposure treatment was the second highest portion of the costs (35 %). 

Ewaldus (orange shirt) and his data collection team in one of the villages in the field research

In Flores Island, there is a tendency towards less preventive measures and more PET. However, in the long run that may be more expensive then prevention. Next steps in the research are going to be aimed at the willingness of dog owners to co-operate with preventive measures and the costs-benefit of preventive measures. So you will be hearing more about his research in the future. 

One of the benefits of travel: Ewaldus took me to Kelimutu lakes, a beautiful spot, where volcanic lakes have totally different colours that even change over time. 

Mastitis detection on farms with an AMS

What a little tweet can do. A couple of weeks ago we had the annual meeting of the Dutch Mastitis Research workers. Dutch is here: Dutch language, because we meet with the mastitis research workers from the Netherlands as well as from Flanders (Belgium). It had my laptop with me and an internet connection, so from each talk I made a tweet. Personally I presented research entitled: "Consequences of farmers' interpretation of mastitis alerts". This work was done as research internship of a veterinary student (Klaske Buma, she is now working as practitioner) and mostly supervised by my colleague Ruurd Jorritsma from the Faculty of Veterinary Medicine. 

The tweet of this presentation was: Results of internship of Klaske Buma: #AMS farmers check only 3.5% of mastitis alerts. As a result 74% of mastitis cases is missed 

As a result almost all Dutch farmers journals picked this up and wrote something about this item. Amazing how things go in the land of the journals. But given the interest in this little tweet, it is good to give a little more background on this item.

When milking cows with an automatic milking system (AMS), for mastitis detection, farmers have to rely on sensor alerts. It is known that, although the sensitivity and specificity of current mastitis are quite reasonable, the systems still give a relative large number of false positive alerts. In order to find detect all mastitis cases, farmers have to visually check all alerts. We do know that far from all farmers are doing that. The goal of this research was therefore to study farmers behavior related to mastitis alerts and the consequences thereof.

The study was done on 7 farms, located around one village in the north of the Netherlands. The farmers needed to be motivated to enter the study. All farms were milking with a Lely Astronaut (Lely, Rotterdam, the Netherlands) AMS. Each farm was visited five times. During each visit, the farmers were questioned about the alerts on the alert list of that day. After this questioning, the milk of all four quarters of every cow on the alert list was visually checked for clinical mastitis and was checked for subclinical mastitis using the CMT test.

During the first visit and before checking individual quarters, a questionnaire was held on the criteria farmers used for selecting cows on the alert list to be visually checked. Important criteria for farmers were, an alarming change in milk production, flakes and/or clots on the milk filter in combination with high electrical conductivity or a failed milking. Reasons for not checking alerts were: no flakes or clots on the milk filter, no change in milk production, cows that were repeatedly on the alert list or a lack of time.

In total 421 alerts were studied (see Table). Of all mastitis alerts, 60 % were not associated with mastitis. For the repeated alerts (cows that had been on the alert list earlier), 46 % of the alerts were not associated with mastitis.

Studied alets and mastitis
	Clinical mastitis	Subclinical mastitis	No mastitis	Total
Number of alerts	30	47	150	227
Number of repeated alerts	9	81	104	194
Total	39	128	254	421

Only 15 of the 421 quarter alerts were checked by the farmer (3 % of all alerts). From the checked alerts by the farmers, 67 % had clinical mastitis and 13 % had subclinical mastitis. However, the farmers missed quite a large number of mastitis cases. Of the 39 clinical mastitis cases that were found, only 10 were detected by the farmers, which means that 74 % of the clinical mastitis cases were not (yet) detected by the farmers.

In order to detect all clinical mastitis, farmers should check all alerts visually. For the 7 farmers in this study this would mean that, on average, 12 cows need to be checked each day. The question that remains is: how bad is it that so many cases of clinical mastitis are missed. Well for official EU milk quality regulations that is bad, because milk that has physical abnormalities should be withheld from delivery. On the other hand, many farmers that manually check the milk off their cows do detect flakes or little clots in the milk, squirt a few times more and deliver the milk as well, because the remaining milk is free of clots.

Is it bad for mastitis control? Well I do not know. Are the missed cases detected a few days later and does treatment at that time have similar cure probabilities? What is the probability of spontaneous cure of these "missed" mastitis cases. Interestingly, given all the fuss about this very interesting, but relatively small piece of work, we are thinking about future research.

Finally, for those interested, the topic will also be presented at the coming ECPLF conference in Leuven, Belgium.

Why large animal veterinarians need to know something about economics

On many veterinary faculties, the students receive some teaching in economics. Many times this is provided by an agricultural economist who does not speak the language of the veterinarians very well. Students are taught production economics (the basics of it) and the link between their veterinary profession and the economics is far away. Moreover, economics is not seen as a basic need for veterinarians, especially now more and more veterinarians are moving into companion medicine instead of large animal medicine. The rationale for the economics in the veterinary curriculum was lying in the fact that veterinarians should need a bit about the economics of their customers: the farmers. That is not needed when going for companion animal medicine.

When I started to teach economics at the Faculty of Veterinary Medicine of Utrecht University (hired in from Wageningen) in 2001, I could teach my own course. The course was a combination of production economics as well as animal health economics. And through the time (we are now two curriculum changes further), the amount of economics has decreased. First my course was combined (and reduced) with another course into Veterinary Herd Health Management and now it is part of the course Epidemiology and Breeding. Besides that basic work there are a few lectures and working groups in the Master phase of the curriculum.

When I write this, I am travelling back from Bangkok to the Netherlands. I have given two invited presentations during the ICVS (International Conference for Veterinary Science), held for the 38^th time and organized by the Thai Veterinary Medical Association. It was great to be hosted by a former PhD of our Utrecht group, Chaidate Inchaisri, who is doing interesting disease decision support work now in Thailand at the Chulalongkorn University.

The title of my presentations were Econonomic side of veterinary work. The first presentation gave some economic backgrounds and reasons that economics are important in the veterinary field. The second presentation gave applications of economic calculations on the individual animal, herd and regional level and was meant to make the audience think about possible applications in their own field of work.

I was told on forehand that economics is not seen as being important by many Thai veterinarians and I was programmed parallel with two presentations entitled: New era of antibiotic use. I lost the competition :-). My room was far less filled than the other room. I do understand veterinarians that choose to learn more about treatments, because that comes much closer to the day to day work they are doing. But still I also believe that some understanding of economics is essential for veterinarians working in the field of large animal medicine. Why? I’ll tell you.

There are two reasons:

1.   Veterinarians do give advices to farmers on treatments, disease prevention, etc. Veterinarians are aiming at maximum animal health and do believe that their advice that their advice is the best for the farmer. And I do believe that farmers should be able to trust the veterinarians for that as well. However, the goal of a farmer is not to maximize animal health (at least in most cases not). Farmers also want to make a living, have constraints in time and money and the advice should take that into account (optimizing vs maximizing). Therefore some knowledge about the costs of their advice, vs the benefits in terms of improved animal health, but also improved income of the farmer is thus important.

2.   Veterinarians need to sell their products. For drugs that is easy: in most countries, vets are the only persons that are allowed to sell drugs. There is a tendency, however, that more and more of the income of farmers have to be earned by selling advices, for instance through veterinary herd health and management programs. In order to sell these “products”, the economic consequences (benefits) of these products need to be known. It has been shown that for Dutch farmers economic reasons are an important (but not only) reason for farmers to participate in a veterinary herd health and management program. For farmers not participating, economics were a very important reason not to participate.

Now, should veterinarians know everything about economics? No of course not. I think vets should be able to reason economically and to be able to critically interpret scientific and applied work from people such as myself so that they can support farmers and market their products.

Economics of automatic milking

In the end of November I was invited by DeLaval (Tumba, Sweden) to give a webinar (seminar which was broadcasted over their internal network so that employees from over the world could join) on two topics. The first topic was economics of production diseases and the second topic was on economics of automatic milking. The first presentation was quite similar to the presentation I gave at the World Buiatrics Conference in Lisbon, Portugal (slides can be found here). But the second presentation (slides can be found here) had quite some new research results which I will talk a bit further about in this blog.

I felt in the lion's den because I have been talking and publishing about the economic effects of automatic milking which are not always positive. As you know, automatic milking has become mainstream nowadays. Since the time of the first serious publications on automatic milking the economics of automatic milking has been of interest. These first publications were in the book called: Prospects for Automatic Milking: proceedings of the International Symposium on Prospects for Automatic Milking, a symposium organized by the old IMAG institute. At that time I was working on my PhD and gave a presentation of my own work (on automated diagnosis of mastitis problem, using artificial intelligence), but at that time I was quite skeptical about the prospects of automatic milking: would it really work? Those first robots did not look as elegant as they are now, and the performance was still far from perfect. Obviously I was wrong.

The economic question has since then not let me loose. A series of scientific publications has been made throughout the years, both for European as well as US circumstances. Most of these publications are so-called normative studies. They use estimations of costs of the milking robot, labour savings, production changes and compare this with an equal farm with a conventional milking parlour. These studies give great indications, but they are always theoretical. In 2007 we published a first studie (carried out by Ronald Bijl as an MSc thesis) on the economics of automatic milking based on real economic data, from an accountancy firm called Alfa Accountants en Adviseurs. In total, 62 farms (31 using an AMS and 31 using a CMS) were analyzed for the year 2003, using a case control study. Differences between years 2002 and 2003 also were analyzed, by comparing a sub-group of 16 farms with an AMS and 16 farms with a CMS. Matching was based on the time of investment in a milking system (same year), the total milk production per year, and intensity (kg/ha). Results of 2003 showed that the farms with an AMS used on average 29% less labor than farms with a CMS. In contrast, farms using a CMS grew faster (37,132 kg of milk quota and 5 dairy cows) than farms with an AMS (-3,756 kg of milk quota and 0.5 dairy cows) between 2002 and 2003. Dairy farms were compared financially based on the amount of money that was available for rent, depreciation, interest, labor and profit (RDILP). The CMS farms had more money available for RDILP (€ 15,566) than AMS farms. This difference was caused by larger fixed costs (excluding labor) for the AMS farms, larger contractor costs of € 6,422, and larger costs for gas, water and electricity of € 1,549. Depreciation and interest costs for automatic milking were not available,but were calculated based on several assumptions. Assuming larger purchase costs and a shorter depreciation time for AMS than for CMS, costs for depreciation and interest are larger for AMS farms than for CMS farms. So from that first study we concluded that automatic milking was more expensive than conventional milking. Which means that, automatic milking can be seen as a luxury good.

Very recently, another study was published. Wilma Steeneveld received a grant from WASS (the Wageningen Social Sciences Graduate School) and was able to visit prof. Loren Tauer from Cornell University to co-operate on the application of a relatively new method: Efficiency analysis, based on data envelopment analysis (DEA). With this method, you do not study the net income (or something like that), but the efficiency of a farm. The advantage is that not all inputs need to be translated into money, which is sometimes very difficult for inputs such as family labour and land. Data envelopment analysis compares the levels of inputs and outputs for a given farm against all other farms in the daaset to dermine the relative efficiency of farms. The efficiency of farms is related to the farm that was the most efficient. Data from another accountancy firm, Accon-AVM were used.

There were 63 farms in the data set with an automatic milking system and 337 farms with a conventional milking system, who did not differ from eachother in general farm characteristics. Farms with an automatic milking system had significantly higher capital costs (€12.71 per 100 kg of milk) than farms with a conventional milking system  (€10.10 per 100 kg of milk). Although the  farms with an AMS had a slightly lower technical efficiency (0.76) than the farms with a conventional milking system, this difference was not significant. This indicates that the farms were not different in their ability to use inputs (capital, labor, cows, and land) to produce outputs (total farm revenues).

This means that the economic performance of farms with an automatic milking system are almost equal to the farms with a conventional milking system. Good news for DeLaval, Lely and other manufacturers of automatic milking systems.