Studies on the Appearance of the Centres of Ossification of the Axial Skeleton in the Feline Foetus

ossification of the vertebral column, ribs, sternum and skull of the foetuses of cats was studied radiographicaly. All individuals from 90 litters were radiographed both fresh and after impregnation with silver nitrate. Other were subjected to histologically examination and alizarin red straining. The ages of the litters were estimated using crown-rump length. Thje range of ages was from day 24 after mating to day 63. The times of observation of the first appearance of the centers of ossification were notedc using various techniques and both these times and all the centers for the axial skeleton appearing during foetal life were tabulated. A survey of the relevant literature is also given.