Before the book "Animal machines" was released in 1964, animal welfare was basically seen as a philosophical subject based on the idea that animals are capable of suffering. Several countries had introduced laws to prevent cruelty to animals, but Harrison's descriptions of modern husbandry awoke public interest to the subject. This led to a serious discussion in England, which resulted in the setting up of the Brambell-committee, which was to give an account of the welfare in farmed animals.  

The committee presented its work in a report in 1965. Even today the committee's criteria of good animal welfare, known as the five freedoms, are still used.

- Freedom from hunger and thirst

- Freedom from physical distress

- Freedom from pain, injury and disease

- Freedom from anxiety and fear

- Freedom to carry out natural behaviour


Today, animal welfare is all about the animal's quality of life. One definition that is often used, states that good animal welfare depends upon the animal's ability to cope with its environment, and how the animal evaluates its own situation. Most animals are flexible and adaptable to a certain extent. Their environment does not have to be a copy of their habitat in wild life, but it must be adjusted to the animal's physiological and behavioural needs.

Most farmers are concerned with the welfare of the animals they have in their care. To decide whether the animal's welfare is good or not, one needs scientifically approved methods for measuring and assessing the animal's welfare. One of these methods includes three factors; health, physiological evaluation and behaviour.
Health is the easiest way of judging the animal's conditions. If it is healthy, this may be a sign of good welfare. Factors such as reproductive abilities, growth and fur quality may also be equivalent with good welfare.

Physiological evaluation means measuring for example levels of stress hormones in the animal's blood. One can also measure the heart rate or body temperature. You can learn much about an animal's welfare by studying its behaviour, meaning how it acts. Scientists have great knowledge of the animals' basic behaviour, and how they lived before they were domesticated. The scientists also look at the conditions of the farmed animals of today, and study eventual changes that can be made to improve the animals' conditions further.