Histologically-validated footpad dermatitis scoring system for use in chicken processing plants

Abstract

1. Footpad dermatitis (FPD) is a recognised welfare problem in broiler chickens. Broiler feet (n = 54) were examined macroscopically and microscopically to determine a reliable correspondence between macroscopic and histological features, and to devise a scoring system that was relevant to bird welfare and easy to use at processing plants. 2. Three types of footpad lesion were defined based on their severity. Type I were mild lesions, visually characterised by scale enlargement and erythema, and histologically by hyperplasia and hyperkeratosis of the epidermis, superficial dermal congestion and oedema. Type II were moderate, superficial lesions, visually characterised by hypertrophic and hyperkeratotic scales covered with yellowish to brownish exudate, and histologically by a prominent pustular and crust-forming dermatitis. Type III lesions were the most pronounced, visually characterised by a thick dark adherent crust, and histologically by extensive ulceration. 3. On the basis of the severity and extent of these three types of lesions, a 5-point scale was devised, i.e. no or type I lesion (score 1), type II lesion (<50% or >50% of footpad, scores 2 and 3 respectively) and type III lesion (<50% or >50% of footpad, scores 4 and 5 respectively). 4. The scoring system has the advantage of making sense in terms of welfare compared with previous schemes. Furthermore, it is histologically validated and easy to use for the routine assessment of broiler welfare in processing plants.

Effect of Litter on Development and Severity of Foot-Pad Dermatitis and Behavior of Broiler Chickens

“…Together with the increase of the surface of footpad which is affected with lesions, there is an increase of the depth of the affected skin layers. The described microscopic lesions in this study were very close to those described by other authors (Martland, 1984;Greene et al, 1985;Martland, 1985;Michel et al, 2012). The results showed that applied scoring method (scoring from 0-3) could be applied in monitoring of FPD in welfaremonitoring programs.…”

“…Some authors documented that such litter treatments might have positive effects on the occurrence of FPD (Nagaraj et al, 2007). Since the FPD is recognized as a welfare problem of broilers, a scoring method, that is fully validated histologically, is required in order to accurately define lesions and to establish a clear link between the macroscopic appearance of the lesion and its putative impact on chicken welfare (Michel et al, 2012).…”

Effects of different floor housing systems on the welfare of fast-growing broilers with an extended fattening period

“…Tissue samples were cut to 4 µm and stained with hematoxylin and eosin and examined under a light microscope. Gross and histopathologic evaluations were largely based on Michel et al (2012). However, a slight modification was made since there were no cases of slight redness or abrasion in the specimens.…”

Technical assistance to the Commission (Article 31 of Regulation (EC) No 178/2002) for the preparation of a data collection system of welfare indicators in EU broilers’ slaughterhouses

“…These scores are then weighted and summarised to give a total flock score, which is used as a direct indicator of foot pad dermatitis and an indirect indicator of litter quality and bird management. A similar scoring system using a five-point scale with clear visual description of the lesions associated and histologically validated has recently been proposed (Michel et al, 2012). This system could easily be translated in a 3 points-scale with scores from 0 (no lesion or enlarged scales), to 1 (hypertrophic and hyperkeratotic scales covered by yellowish to brownish exudates), to 2 (depressed lesion, ulceration, with or without dark thick adherent crust).…”