Measure welfare of dairy cattle with biomarkers
How do you objectively determine the degree of well-being of dairy cows? After all, you can't ask them. This project is looking for easily applicable biomarkers other than blood, which are a measurable indication of welfare in dairy cows, established by a behavioral test.
There is great public interest in the welfare of farm animals. The Dutch dairy sector considers a good level of animal welfare on dairy farms as an important quality criterion for sustainable dairy farming. But how do you simply "measure" the welfare of dairy cows? The current methods for monitoring the health and well-being of dairy cows, such as Cow Compass, are labor-intensive and therefore relatively expensive. Moreover, specific observation criteria for "positive" well-being are lacking.
Research with humans shows that the emotional state (from positive to negative) is related to variation in certain hormones and other biologically active substances in body fluids such as blood and saliva. We call these substances "biomarkers". For dairy cows, we may find such biomarkers in milk, urine, manure, saliva and hair; so our own products that we can collect and analyze without physical interventions.
The project approach is based on a combination of three recent developments in scientific research.
1. Relationship between well-being, emotional state and biomarkers
Animals, like humans, have the ability to experience feelings and emotions; negative feelings, for example with pain or fear, and positive feelings, for example when receiving tasty food or during positive social contact with peers. Animal welfare is not directly measurable. In essence, welfare relates to the emotional state of the animal.
2. Measuring the emotional state in animals
People can be asked about their feelings and their emotional state. Of course this is not possible with animals. Recent research supports the idea that the emotional state of animals can be measured indirectly and objectively in a specific behavioral test.
3. Non-invasively measuring biomarkers in animals
Great progress is being made with the frequent and as far as possible non-invasive (without physical interventions) measurement of neuroendocrine and physiological biomarkers in (farm) animals in biological materials such as milk, urine, manure, saliva and hair, and of physiological and behavioral variables using sensors.
Groups of cows are exposed to husbandry conditions under controlled conditions, which we assume cause a difference in emotional state in the cows, ranging from negative to positive. The emotional state of cows is then measured using a specific behavioral test. At the same time, potential biomarkers are measured in these animals, both in blood (as reference) and in biological materials other than blood. In doing so, we look for meaningful equivalents of biomarkers that in humans are demonstrably related to the emotional state.
Perspective-rich biomarkers - i.e. those biomarkers that vary systematically with the emotional state of cows - are also determined under practical conditions. On the dairy farms, the potential biomarkers are measured in a sample of cows. In addition, the welfare level on the companies is mapped with existing observation protocols such as "Cow Compass". In this way, it is possible to look at possible links between welfare scores obtained with, for example, 'Cow Compass' and the values of biomarkers.
Identifying easily measurable biomarkers that are related to the emotional state of dairy cows lays the foundation for a unique tool that enables us to objectively determine the welfare of dairy cows in a feasible and standardized manner.