Abstract:

Preventive veterinary medicine and prophylactic programmes particularly when applied to industrialised animal production operations (meat, eggs and milk) are more efficient in an economic sense than curative veterinary medicine and therapeutic treatments. The concept of "economic diseases" that is to say, of diseases which show only a slow down of animal performances (weight gain, eggs or milk output, feed conversion rate) without further visible pathological symptoms, is proposed as a theoretical means for understanding the necessity to work out and implement a prevention programme. This programme must take into account the numerous factors of disease in a given flock or herd under given conditions and set priorities among those factors.