Fig. 9. Delayed ossification in rs/rs. (A,B) Skeletal analysis at the newborn stage revealed delayed ossification in metatarsal and phalangeal bones of the hindlimb (dorsal view, right side) from wild-type (A) and rs/rs (B). (C-F) Histology of non-decalcified bones from the contralateral (left) side of the hindlimbs from the same newborn animals. The corresponding areas is indicated by the boxes in A and B (the proximal phalanx of the second toe). In C and D, sections are stained by Alcian Blue, while sections are stained Alizarin Red and hematoxilin in E,F. Note the absence of Alizarin Red staining in the region of chondrocyte hypertrophy. The zone of prehypertrophic chondrocytes starting to undergo hypertrophy (brackets with ph in E,F) seems reduced in rs/rs. Scale bars: 100 µm.