Iraqi Journal of Veterinary Sciences

Abstract

Forty Local Awasi sheep fetuses were collected from several areas in Ninevah Governorate, further than local slaughterhouse. Their estimated ages calculated depending on crown-rump length with the aid of Richardson formula. The study aimed to detect the site and the time of appearance of ossification centers in the hind limb bones of Awasi sheep fetuses by using modified double staining method to demonstrate cartilage and bone , or by using radiography. The first ossification centers appeared in the hind limb bones was the primary center of the tibia and femur ,metatarsus with ilium then ischium at 45 , 46 , 48, 50-52 days of fetal age respectively. The ossification centers of pes phalanges appeared in the following sequence ; distal phalanx ,followed by the proximal phalanx and end by middle phalanx , at 58 ,60, 64 days respectively. Ossification centers of tarsal bones began to appear in calcaneus at 64 day , talus at 77 day , central & 4th tarsal bones at 96 day ,, followed by centers of 3rd & 2nd tarsal bones at 100 day while, the center of 1st tarsal bone appeared lastly at 105 day.Femur , tibia and metatarsus studied statistically by follow up the relative increase of their total lengths and length of their ossified part of diaphysis , the results show high significant variance in their growth and ossification of the three bones in first studied period (46-60 days) in comparison with the next sixth successive fortnightly periods