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

Human impact erodes chimpanzee behavioral diversity

Chimpanzees possess a large number of behavioral and cultural traits among nonhuman species. The “disturbance hypothesis” predicts that human impact depletes resources and disrupts social learning processes necessary for behavioral and cultural transmission. We used a dataset of 144 chimpanzee communities, with information on 31 behaviors, to show that chimpanzees inhabiting areas with high human impact have a mean probability of occurrence reduced by 88%, across all behaviors, compared to low-impact areas. This behavioral diversity loss was evident irrespective of the grouping or categorization of behaviors. Therefore, human impact may not only be associated with the loss of populations and genetic diversity, but also affects how animals behave. Our results support the view that “culturally significant units” should be integrated into wildlife conservation

L'ALLAITEMENT ARTIFICIEL DES AGNEAUX. IV. — COMPARAISON DE DIFFÉRENTES SOURCES DE MATIÈRES AZOTÉES EN REMPLACEMENT DE LA POUDRE DE LAIT

International audienc

Preventing on-farm infections through genetic selection

International audienc