'Animal welfare' is the desire to prevent unnecessary animal suffering. That is, whilst not categorically opposed to the use of animals, wanting to ensure a good quality of life and humane death.

(Source: www.worldanimal.net). 

The European Commission has defined the so-called "Five Freedoms" to define ideal states of animal welfare:

1. Freedom from hunger and thirst - access to fresh water and a diet for full health and vigour;
2. Freedom from discomfort - an appropriate environment with shelter and comfortable rest areas;
3. Freedom from pain, injury and disease - prevention or rapid treatment;
4. Freedom to express normal behaviour - adequate space and facilities, company of the animal’s own kind;
5. Freedom from fear and distress - conditions and treatment which avoid mental suffering

(Source: European Commission).