Thermal imaging cameras keep dairy health in check

Far from being stuck in the past, large-scale farms increasingly resemble factories as they become more and more industrialised. Farmers spend less time in the paddock and more time in front of the computer. In these circumstances, good automatic monitoring systems are a must to ensure quality and continuity.

“A big problem in present-day dairy farming is a disease called mastitis,” said Ellinor Eineren, founder of Agricam, a Swedish company that has developed an automatic monitoring system for dairy cows using thermal imaging cameras.

“Mastitis is a persistent inflammation in cow udders. This potentially fatal mammary gland infection is the most common disease in dairy cattle. It can be treated very easily if diagnosed at an early stage. Usually the infected cow will simply be milked more often to ensure that the bacteria that cause the infection has little to no milk left in the udder in which to replicate. This allows the animal’s natural defence system to get rid of the bacterial intruder before the mastitis becomes clinical.”

In the days of manual milking, diagnosing mastitis was a relatively easy task. The disease causes a rise in temperature in the udder, which a hands-on farmer would be able to detect while milking. Now that milking is carried out by machines, early mastitis symptoms are difficult to detect.

Automatic analysis software uses advanced algorithms to detect developing mastitis in thermal images of cow udders.

“Mastitis causes pain and general discomfort for the animal and requires treatment with antibiotics. This not only leads to veterinary costs, but also - due to strict regulations throughout most of the world - the milk must be discarded until the entire antibiotic drug residue has left the animal’s system,” said Eineren.

“I was shocked to find that the average European dairy farmer is currently losing €20,000 to €60,000 [AU$30,000 to AU$90,000] each year due to mastitis. We therefore set out to find a solution to the problem: an automatic early detection system based on thermal imaging technology.”

Veterinarians all over the world use handheld thermal imaging cameras to detect inflammations in domesticated animals. From horses and cows to dogs and cats, thermal imaging cameras are becoming more and more accepted by animal health professionals as a diagnostic tool for inflammation and other health issues.

“But in those cases there has to be a human operator present to manually record the images and to analyse the thermographic data. To my knowledge there is no system available that can do this automatically,” said Eineren.

This is why Eineren and Agricam developed a patented system called CaDDi, an abbreviation of Cattle Disease Diagnostics. “We cooperated with the Linköping-based FLIR products distributor Termisk Systemteknik to test the feasibility of such a product. The first thing we did was to determine whether thermal imaging cameras can detect mastitis by manually recording thermal images of cow udders with a FLIR P660 thermal imaging camera and analysing the resulting thermal images in cooperation with veterinarians from the Swedish National Veterinary Institute,” Eineren said.

To protect the thermal imaging camera against the adverse conditions in a dairy farm, the cameras are mounted in a waterproof housing with automatic window cleaning system.

“The next step was to build a system that could do that automatically, but that was easier said than done. Not every warm area in the thermal image indicates an inflammation. Animals’ body temperatures fluctuate naturally and there also are many subtle differences between thermal patterns of individual animals. We therefore needed advanced analysis to prevent unwanted alarms. In that area we greatly benefited from the expertise of our partner Termisk Systemteknik.”

“Here at Termisk Systemteknik we have over three decades of experience in all sorts of image analysis, including the analysis of thermal images,” said Termisk Systemteknik’s CEO Stefan Sjökvist. “But this particular application was still a difficult challenge, as we needed to take into account the particular thermal properties of each individual animal to be able to achieve an accurate result.”

Sjökvist and his colleagues installed two FLIR A310 thermal imaging cameras in rugged waterproof housings at the sides of the milking machine in a dairy farm. “With a thermal sensitivity of 50 mK and a resolution of 320 x 240 pixels, the FLIR A310 thermal imaging cameras provide exactly the kind of detailed images and thermal data that we need for this application,” he said.

The CaDDi system.

The two cameras recorded thermal images of the dairy cows’ udders for a period of six months. Using the automatic identification system, which was already part of the milking machine, a database of thermal images was created for each individual cow. “Using that database the software determines the normal thermal patterns of each individual animal. By comparing each new reading to the earlier recorded data the system can now accurately detect the type of thermal anomalies that indicate mastitis. And the accuracy of this evolving system will improve as the database expands,” said Sjökvist.

The two FLIR A310 thermal imaging cameras record images of the cow's udder from both sides.

Plans are afoot to expand the system to other health issues. “The technology should be able to detect a wide variety of health issues, such as other types of inflammation, nerve damage, skeletal problems or injuries, even before the animals exhibit any clinical symptoms,” said Eineren.

“The product we currently market is CaDDi Mastitis, but in the future modules for other diseases and for other animals will be developed. We work closely with veterinarians from the Swedish National Veterinary Institute to verify the accuracy of all our present and future modules.

“In an early stage of concept development we compared the thermal imaging products available on the market today, but we soon learned that there is no other thermal imaging supplier that provides solutions with the same level of performance while remaining as cost effective as the thermal imaging solutions offered by FLIR Systems.”