Evaluation of welfare parameters in laying hens on the basis of a Bavarian survey.

Health issues like infestation with poultry red mite (Dermanyssus gallinae) and behavioral problems such as feather pecking and cannibalism are reported as current problems on laying hen farms. However, the epidemiological prevalence of these issues in Bavaria, Germany, is not known. The objective of the present survey was to determine the epidemiological prevalence of health and behavioral parameters and the management of hen farms in practice. The survey was sent to all laying hen farmers with more than 1,000 hens in Bavaria, Germany, and contained questions regarding flock management, behavior problems and health issues. The response rate was 40.8% and surveys were answered regarding 293 individual flocks on 147 farms. Three-quarters (77.6%) of the respondents housed their hens under conventional conditions. Farming system had an influence (P ≤ 0.05) on several management measures and the hens' behavior. An infestation of the flocks with poultry red mite was stated in 65.7%, whereby a relationship existed with the farming system (P = 0.001) and the provision of an additional dust bath (P ≤ 0.001). The occurrence of feather pecking (18.5%) was related with the farming system (P = 0.001), the presence of roosters (P = 0.034), the locking of laying hens into the aviary (P = 0.006), not allowing access to the entire litter space after housing (P = 0.044) and nervous (P = 0.002) or chasing behavior (P ≤ 0.001) of laying hens. Similarly, cannibalism (15.0%) was related with locking hens into the aviary system (P ≤ 0.001) and not allowing access to the entire litter space (P = 0.026). According to these results, farmers should avoid locking the hens into the aviary or not allowing access to the entire litter space, because these measures relate to nervous behavior that may result in feather pecking or cannibalism. The provision of an additional dust bath is one of the management measures that can positively influence hens' health and behavior.

Expression pattern differences between osteoarthritic chondrocytes and mesenchymal stem cells during chondrogenic differentiation.

OBJECTIVE: The use of mesenchymal stem cells (MSCs) for cartilage regeneration is hampered by lack of knowledge about the underlying molecular differences between chondrogenically stimulated chondrocytes and MSCs. The aim of this study was to evaluate differences in phenotype and gene expression between primary human chondrocytes and MSCs during chondrogenic differentiation in three-dimensional (3D) pellet culture (PC). MATERIALS AND METHODS: Chondrocytes isolated from cartilage samples obtained during total knee alloarthroplastic procedure (N=8) and MSCs, purified from bone marrow aspirates of healthy donors (N=8), were cultivated in PC under chondrogenic conditions. Immunohistology and quantitative reverse transcribing PCR (RT-PCR) were performed for chondrogenic-specific markers (i.e., Sox9, Collagen II). Global gene expression of the so-cultivated chondrocytes and MSCs was assessed by a novel approach of microarray-based pathway analysis. Refinement of data was done by hypothesis-driven gene expression omnibus (GEO) dataset comparison. Validation was performed with separate samples in transforming growth factor (TGF)ß+ or TGFß- conditions by use of quantitative real-time RT-PCR. RESULTS/CONCLUSIONS: Chondrogenic commitment of both cell types was observed. Interestingly, chondrocytes demonstrated an upregulated fatty acid/cholesterol metabolism which may give hints for future optimization of culture conditions. The novel microarray-based pathway analysis applied in this study seems suitable for the evaluation of whole-genome based array datasets in case when hypotheses can be backed with already existing GEO datasets. Future experiments should further explore the different metabolic behaviour of chondrocytes and MSC.