Animals, Stress, And Kosher Slaughter

Animal welfare at the time of death is as important as welfare during animals’ lives on farms. Stress can cause the release of cortisol and other catecholamines (epinephrine and norepinephrine) into the bloodstream, which may cause changes affecting meat quality (tenderness and appearance). Of course, in addition to affecting meat quality, stress at the time of death is often related to fear and distress caused by the environment, human-animal interaction, the method of restraint, and the method of slaughtering.

In this study, kosher slaughter was compared against the conventional slaughter method that uses pre-stunning before bleeding out. Kosher slaughter is a very controversial topic as some Jewish people consider this method more humane than others, and feel that there is a political motivation for asking for changes in this method, as previously reviewed by Faunalytics. However, as previously mentioned, stress at the point of death goes against consumers’ interest for a good quality product, and, of course, animal welfare.

The authors of this study compared physiological stress indicators in 60 male beef calves that were slaughtered using either a conventional (pre-stunning) or Kosher (non-stunning) method. They took blood samples at three points in the animals’ lifetime: on the farm, after transportation to the slaughterhouse, and immediately after slaughter. Only the calves that were slaughtered using the Kosher method showed higher levels of cortisol, dopamine and norepinephrine immediately after slaughter than those slaughtered using the conventional method. According to the authors, this shows that the Kosher method caused higher stress to male beef calves at slaughter.

It’s important to note that calves in this study that were slaughtered following the Kosher method were put in a full inversion rotary pen. This pen must hold the animal tight in a comfortable manner while turning him/her upside down. Well-known animal welfare scientist Dr Temple Gradin ranked the rotating restraint box as conditional acceptable for animal welfare, meaning that the method may be accepted only if the equipment has certain features (e.g. large adjustable side) and the animal is slaughtered within 10 seconds after inversion. This is to reduce the time the animal is held in a position that causes stress while conscious.

In other words, the restraint method in this study may have caused distress to the calves in addition to the slaughtering method used. This may also explain why calves slaughtered using the traditional method may have not shown excessive stress (e.g. high cortisol levels) as this method holds the animal in an upright position.

Another observation made by the study was that: “The animals selected at the end of Step 1 by the Rabbis for the religious rite are usually the most docile and gentle”. This was mentioned as authors observed that calves in this group had lower cortisol and catecholamines levels when measured at the farm. Calm and relaxed animals might not show signs of distress as more reactive animals might, something that may be confused with animals not feeling pain or distress during slaughter. The latter is an assumption that will need further investigation.

Though religious slaughter is a contentious topic, it is an area that needs further research and a strong campaign based on scientific knowledge. Advocates interested in this area need to also consider that scientific findings may not be clear cut as, sadly, not many studies consider the use of animal based indicators such as behaviour to measure welfare.