Animals slaughtered on the farm had twenty times less cortisol in their blood than animals slaughtered in the abattoir. This is the finding of a recent study by Spengler Neff et al. on cattle from the Rengoldshausen (Überlingen, DE) Demeter farm [1].
Before being slaughtered, animals experience various stressful situations. Separation from the herd, transportation, and unfamiliar noises and smells in the abattoir result in an increase in the level of cortisol in their blood serum. Cortisol, like adrenalin and catecholamine, is a stress hormone. The animals' stress decreases meat quality, and both tenderness and water-holding capacity can be adversely affected.
For the study, eleven cattle from the farm were slaughtered at the abattoir a short distance away (ten minutes transport time). Ten cattle were slaughtered on the farm for comparison. All the cattle were of the Original Braunvieh breed and had been born and raised on the farm. Both groups included both male and female animals. Shortly before stunning, the animals' behaviour was observed and classified using a three-level score (Score 1 = calm, Score 2 = unsettled, Score 3 = nervous). The concentration of cortisol was measured in the laboratory from blood samples taken from the slaughtered animals. In addition, the levels of glucose and lactate were recorded using a rapid test during bleeding. Along with the cortisol, these two values give an additional indication about stress. Their production increases in response to an increase in the release of cortisol, providing energy for flight.
All three parameters – cortisol, glucose and lactate – were significantly higher in the animals slaughtered in the abattoir than in those slaughtered on the farm: the cortisol content was on average twenty times higher. This unexpectedly large difference has not been recorded in any previous study. Glucose levels were four times higher and lactate levels twice as high. There were also differences in the observed behaviour before stunning. While in the abattoir all animals were either unsettled or nervous (Score 2 and 3), on the farm half of the animals were calm (Score 1), three animals unsettled (Score 2) and only one animal nervous (Score 3). The behaviour of one animal was not recorded. There was only a minor difference between sexes, and slaughter age had no effect on behaviour.
All the parameters in this study, particularly the large difference in cortisol, showed that on-farm slaughter creates significantly less stress for the animals. Any potential effect of time of day on the cortisol level – a parameter that fluctuates naturally during the course of the day – can be excluded due to the fact that stunning almost always took place at the same time of day.
In biodynamic agriculture the animal makes an important contribution to the diverse farm organism, and its dung provides valuable fertiliser which is essential for soil fertility. Animals are kept as far as possible in a manner appropriate to the species and are treated with dignity and respect. Slaughtering the animal on the farm or the field permits the farmer to maintain this respectful attitude right to the end of the animal's life.
The manner in which an animal is kept and slaughtered has an effect on the quality of the meat: stress before slaughter reduces this quality. This is demonstrated by a faster decrease in pH, a slower decrease in temperature, and meat that is generally less succulent. The meat becomes tough, so that the effect of stress can be detected by the consumer. Something that has received little attention, is how stress hormones that are absorbed by eating the meat impact on the human body. The average consumption of meat in Europe was approx. 65 kg per person in 2020 [3]. Most of this comes from abattoirs. In comparison, only approx. 35 kg of meat is consumed per year on a global scale.
Animal welfare is an important criterion when buying meat, so the slaughter method is a significant issue. There are fewer and fewer regional abattoirs, meaning that transport distances are getting longer. This increases the stress on the animals. In Switzerland, on-farm and field slaughter has been permitted since July 2020 under specified conditions. Around 100 Swiss farms have obtained approval for this, and interest in the practice is growing. In the EU, on-farm and field slaughter have been permitted since March 2021 under specified conditions.
Bibliography
[1] Spengler Neff A, Probst J K, Knösel M. 2023: «Hoftötung oder Tötung im Schlachthof: Unterschiede bei stressanzeigenden Parametern» Agrarforschung Schweiz
14:90–95. doi.org/10.34776/afs14-90
[2] Reiche A-M, Oberson J-L, Silacci P, Messadène-Chelali J, Hess H-D, Dohme-Meier F, Dufey P-A & Terlouw, E M C. 2019: "Pre-slaughter stress and horn status influence physiology and meat quality of young bulls." Meat science
158. doi.org/10.1016/j.meatsci.2019.107892
[3] FAO (Food and Agriculture Organization of the United Nations)
. 2021: "Meat" www.fao.org/3/cb5332en/Meat.pdf accessed on 20.06.2023
[4] Bundesanstalt für Landwirtschaft und Ernährung. 2023: "Fleischverzehr 2022 auf Tiefstand"
www.ble.de/SharedDocs/Downloads/DE/Pressemitteilungen/2023/230403_Fleisch.pdf;jsessionid=64173262EB4836B265C305452625AF8F.internet971 accessed on 18.06.2023