Endotoxin concentration in poultry houses for laying hens kept in cages or in alternative housing systems

International audience1. Endotoxins as components of organic dust may have adverse effects on the respiratory health of workers in poultry buildings. The move towards more welfare-friendly housing systems for layers may increase worker exposure to air contaminants due to the use of litter. 2. The endotoxin concentrations in the inhalable fraction of airborne dust (below 100 µm) from cage and alternative system henhouses (on-floor, free range and aviaries) were compared under both experimental and commercial conditions. 3. The endotoxin concentration was higher in experimental aviaries (median: 565 EU/m3, range: 362-1,491 EU/m3) than in cage housing (98 EU/m3 (51-470)). 4. In field conditions, the endotoxin concentration in the air of 13 alternative henhouses was higher (35 to 3,156 EU/m3) than in cage system buildings (n=8, 78-576 EU/m3). It was correlated to the respirable dust concentration (fraction below 5 µm) and to the temperature inside the henhouse but no seasonal variation was observed. 5. The present study emphasizes that considerable worker exposure to endotoxins may occur in henhouses especially in alternative systems

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

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% of footpad, scores 2 and 3 respectively) and type III lesion (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

Phylogenetic relationship between Dermanyssus gallinae populations in European countries based on mitochondrial COI gene sequences

Phylogenetic analysis of Dermanyssus gallinae mites originating from UK, France and Italy was performed using partial amplification of the mitochondrial COI gene. Results showed that UK samples reveal the greatest variation and diversity and are linked to one of the French populations highlighting North–South genetic transitions in European red mite populations. Intra-farm variations between mite samples highlighted the diversity between national populations and possibly its origin from the different chemical strategies used in each country