First validation of a prototype of multi-spectral camera to quantify skin lesions in pigs
Résumé
The aim of the present work is to detect and quantify skin lesions with fresh or coagulated blood in pigs. If
successful, this objective technics will replace on-farm detection by an observer as described in scientific papers
or in the Welfare Quality® protocol. Therefore, it could be used for welfare assessment in scientific experiments,
for welfare certification, for genetic selection against aggressiveness or for farmers to have an objective evaluation
of behavioural problems occurring in their farms. The method is based on a method described by Goel et al. Six
images are acquired by an active camera with projection of light characterized by 6 different wavelengths. These
wavelengths were chosen so that haemoglobin could be specifically absorbed, and hence detected, at least by one
length. The images are taken successively in a short interval of time so that that they are well superposed. These
images are analysed by a software which allowed, in a first step, to produce 2 images: a well-defined image of the
pig (left image below), a white and black image (right image below) where pixels in black corresponds to skin
lesions with blood and pixels in grey to the skin without blood. An area of the body with skin lesions is depicted
inside the white circle in both images. Some work is still undertaken to reduce the time interval between images,
improve the software and validate the method.