The radiographic identification of the various stages of pregnancy in the domestic cat

By radiographing intact, recently killed, pregnant cats and then removing the foetuses for crown-rump measurements, a correlation between radio-graphic appearance of foetuses in utero and foetal age is established. The radiographic appearance of the foetuses in utero is described from the twenty-fifth day of pregnancy until full term.

SUMMARY

Using the CR length measurement to assess foetal age, a method of approximately estimating the various stages of pregnancy in cats using radiography was produced. It was seen that, although uterine enlargement and displacement was seen as early as the 25th day, the first signs of the foetal skeletal system were not apparent in utero until the 38th day. From this time a progressive pattern of appearance of ossified parts was noted which allowed a means of estimating the day of gestation.
Résumé. En radiographant des chats en gestation, récemment tués et intacts et en éloignant ensuite le foetus pour mesurer la couronne et la croupe, une correlation entre l'aspect radiographique du foetus in utero et l'âge du foetus est établie. L'aspect radiographique du foetus in utero est décrit depuis le vingt-cinquième jour de gestation jusqu à son terme.
Zusammenfassung. Durch Röntenaufnahmen intakter, kurz zuvor urns Leben gekommener, trächtiger Katzen und anschliessende Entfernung der Foetusse zwecks Scheitel-Rumpf-Messung wurde eine Beziehung zwischen der röntgenologischen Erscheinung der Foetusse in utero und dem foetalen Alter hergestellt. Die röntgenologische Erscheinung der Foetusse in utero wird vom 25. Tag der Trächtigkeit bis zum Austragen beschrieben.