Sensor-based monitoring of the prevalence and severity of foot pad dermatitis in broiler chickens.

1. The aim of this study was to assess the suitability of a dielectric measurement to evaluate the prevalence and severity of foot pad dermatitis (FPD) in broiler chickens. 2. The study focussed on surveying the occurrence of FPD during the growing period of one broiler chicken flock. A scoring system consisting of 5 categories was used to assess the prevalence and severity of FPD macroscopically. Additionally, the dielectric constant (DC) of both foot pads of 50 chickens was measured in a triple iteration with the MoistureMeter D (Delfin Technologies, Kuopio, Finland) on three different dates. 3. On all measurement days, DC and FPD score were negatively correlated. The severity of FPD increased during the growing period, and severe lesions occurred at an early stage. 4. Further research is necessary to develop an effective early warning system for FPD in poultry houses. However, the non-invasive measurement of DC provides a reliable method for the objective assessment of occurrence and severity of FPD.

Keeping laying hens in furnished cages and an aviary housing system enhances their bone stability.

1. Tibia and humerus breaking strength of Lohmann Silver hybrids kept in conventional cages, furnished cages and an aviary with outdoor run were examined in two production cycles. Each trial lasted a full laying period; feeding, management and healthcare were identical for all hens. In both trials bone strength was investigated at the end of laying months 6, 9 and 14. 2. The objective was to determine if bone strength increases when hens are kept in alternative housing systems, especially in furnished cages, and whether hen age affects bone stability. 3. The results indicated that housing system influenced bone breaking strength, which was consistently higher for hens in the aviary compared to hens in conventional and furnished cages. Furthermore, humerus breaking strength was higher for hens in furnished cages compared to conventional cages. No significant difference regarding tibia breaking strength was found between conventional and furnished cages. 4. Our results showed that lack of exercise contributed to the problem of weak bones more than did calcium depletion from eggshell formation. 5. Tibia breaking strength increased during the last third of the production cycle, whereas humerus breaking strength remained unaffected by hen age. 6. Genetic group affected only tibial bone breaking strength, which was lower overall in genetic group A than in group B, which in turn was lower than group C. 7. The increased bone strength in the aviary and in the furnished cages probably reduced the incidence of recently broken bones in these systems compared to the conventional cages. This increase in bone strength can be regarded as an improvement in welfare. Furnished cages, like the aviary system, might be considered an alternative housing system for laying hens, because both resulted in enhanced bone strength.