Figure 5.

The influence of AKG supplementation during the experimental period (31–60 weeks of age) on the distribution of cartilage oligomeric matrix protein (COMP) in laying hens at the age of 60 weeks. Representative pictures of the immunohistochemical analysis of COMP carried out on formaldehyde-fixed sections from the tibial articular cartilage of laying hens from the control (CONT) and AKG supplemented (AKG) groups. Cartilage from the control and AKG supplemented hens show differences in the quantity and distribution of COMP (brown color). Tissues with anti-COMP antibody, control cartilage, show a lower accumulation of COMP throughout the whole thickness of the cartilage, while cartilage from the AKG-supplemented hens shows denser and darker staining, indicating higher COMP deposition, especially in the upper zones of the cartilage. All scale bars represent 200 μm.