Determination of Bone Developments of Rat Anterior and Posterior Extremity Bones in Prenatal and Postnatal Period by Double Staining Method

Aim: In our study, we aimed to determine the morphological development of the bones of the anterior and posterior extremity by staining the rat fetus and offspring skeletons with the double staining method. Method: In the current study, seven groups three prenatal (16th, 18th, and 20th days) and four postnatal (0th, 3th, 7th and 12th days) were formed from the foetuses and offsprings obtained from 13 pregnant rats. Then, it was stained with double staining method. Anterior and posterior extremity images of the fetuses and offsprings were examined under a stereo microscope, and ossification findings were determined. Total bone and ossification lengths as well as ossification areas were measured using the ImageJ software. Results: The first cartilage destruction in fetuses occurred on the 16th day of pregnancy in the clavicle, scapula, humerus, radius and ulna; It was seen in the femur, tibia and fibula on the 18th day of pregnancy. The first ossification centres were in the clavicle, scapula and humerus on the 18th day of pregnancy; It was seen in the radius, ulna, femur, tibia, fibula and 2-5 metatarsal bones on the 20th day of pregnancy. The secondary ossification centre was seen on the 0th day (birthday) in the scapula and humerus, on the 7th day after birth in the ulna and radius, and on the 12th day after birth in the femur and tibia. In the study, while the ossification rate in 20-day-old foetuses was 48.9% in the humerus, 53.2% in the radius, 55.7% in the ulna, 33.6% in the femur, 43.2% in the tibia, 44.3% in the fibula, it was determined that it reached 69.7% in the humerus, 78.4% in the radius, 73.3% in the ulna, 63.5% in the femur, 75.5% in the tibia, and 69.2% in the fibula on the 12th day after birth. Conclusion: In this study, we revealed the morphological changes of the anterior and posterior extremity bones of fetuses and offsprings in the normal developmental course. We think that these results will shed light on the studies to be conducted on the detection of skeletal anomalies in teratological studies and contribute to a more comprehensive evaluation of the findings to be obtained from the studies to be conducted.