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Milk quality antibiotics sensor

Periodic Reporting for period 3 - MILQAS (Milk quality antibiotics sensor)

Reporting period: 2018-05-01 to 2019-03-31

For dairy farmers treating their cows for mastistis with antibiotics is a necessity, however, even small amounts of antibiotics in the milk used for consumption is intolerable. Thus, they need to make sure that the milk from treated cows will not be mixed with milk from other cows for a number of days. Sometimes this occurs by accident either because the specific cow needed longer than usual retention time or if the wrong cow is taken into retention. If that happens the milk from the treated cow will end up not only being mixed with milk from all other cows from the farm but also from other farms when transferred to the milk truck. Presently, the milk is tested for antibiotics on milk truck level when it arrives at the dairy. If antibiotics are found the milk will be incinerated and the milk truck will be cleaned. This takes it out of service for the day. The bill for this is send to the farmer with antibiotics residues in the milk. Both for the dairies and for the farmers it will be an advantage to move the antibiotics test to the farmers site as less milk will go to waste. Such a test must be made so that it can be operated at the farm by personel who are not laboratory trained (e.g. the truck drivers or the farmer). It also has to be fast such that the milk pick-up round time will not increase considerable. It needs to be cheap, such that the total cost of testing at farm level is lower than the cost from the milk that would otherwise be wasted. The test off course has to give the correct result every time and be able to measure all the antibiotics types that are used by dairy farmers. Those are antibiotics from the families of beta-lactams, tetracycline and sulfonamides.
The aim of the project is to produce cheap, fast, easy-to-use, reliable and handheld field tests for measurements of all relevant antibiotics for the dairy industry. Cheap means below 5 Euros per test. Easy-to-use means just dip the chip in milk and insert it in the handheld reader, read off green or red blink - the system will take care of all data management. Reliable means correct result every time. Fast means below 3 min. Together these requirements sums up to a sensor system that will be used at many European farms.
The PlastiSens antibiotics system consists of four parts; a plastic based sensor chip, a handheld electronic reader; a mobile APP for data management and a database for data storage. One end of the sensor chip is shortly dipped in milk, after which the other end of the chip is inserted in the reader which applies the appropriate voltages and measures the output from electrodes responding to the presence of antibiotics. The handheld reader device has been developed for measuring multiple antibiotic families in milk and the first prototypes of this reader has been produced and tested. The reader is very simple on the outside and the operator only needs to slide in the sensor chip. After measuring a green light is blinking on the reader if the milk was free of antibiotics and red if the sample is contaminated. A blue blink is showing that data is transferred via Bluetooth to a paired mobile phone. If the data cannot immediately be transferred they are stored in the reader until there is again connection to the mobile phone. Simultaneously the reader sends the data to a database which can be accessed by the user (e.g. the dairies). The mobile APP has been designed and programmed for both Android and IOS and displays both the results and recommended actions. It can be chosen to look further into the data in the APP. The specifications for the sensor chips and the reader system has been made in collaboration with the dairy company Arla Foods in order to accommodate the users needs.
Measuring antibiotics levels close to their source has several advantages. One is less milk waste, which also means less energy consumed due to a more efficient milk production. On the same note the climate effect originating from milk production is decreased. The major part of greenhouse gasses from cattle is methane (CH4) and nitrous oxide (N2O). Both of these have a greenhouse effect contribution of 25-30 times that of CO2. In Denmark, production of one liter of milk emits 0.9 kg of CO2 equivalents regarding greenhouse effect. There are about 150-200 incidents per year alone in Denmark of milk trucks carrying antibiotics contaminated milk and each truck is loaded with approximately 30 ton of milk. This in total cause an emission of approximately 5.400 ton of CO2 equivalents per year in Denmark only. Denmark has the on average most efficient and second largest milk farms in Europe. This means that the greenhouse effect from 1 L of milk produced will be higher in most other countries. Danish milk production is about 4% of the EU15 countries (~3.5% of the EU28 countries) according to 2015 statistics. Thus, within the EU15 countries there is a potential of saving at least 130.000 ton of CO2 equivalents per year by bringing the antibiotics measurement to all EU15 farms. Great Britain, which together with Sweden probably will be the second market where the PlastiSens ApS technology is introduced, has a milk production of about three times that of Denmark.

Additionally, introducing the technology has a significant economic impact. When a milk truck has been found to be contaminated, the farmer with antibiotics in their milk is asked to pay for the all the milk in the truck as well as for cleaning of the truck's milk tank. This adds up to about 13.000 Euro, a quite considerable amount for most farmers.
Antibiotics use and spread of antibiotics through food intake is a great concern as antibiotic resistant bacteria is an increasing problem with fatal consequences, especially in pig farms and in the human digestive system. Detection of the antibiotics close to the source can limit the spreading of antibiotics and thereby the evolution of antibiotic resistant bacteria.

PlastiSens is not aware of any other feasible solutions for monitoring antibiotics contamination at the farm level, and collaborating leading dairy companies are stating that they have not been presented with any other technology than that of PlastiSens ApS, which can measure antibiotics fast and simple enough for them to be practically usable at the farms.