Radiographic study of postnatal development of the tarsus in west African dwarf goats.

ABSTRACT

Seven goats of the West African dwarf breeds, three females and four males, from the same farm were studied by serial radiography from the first week of life and at 3, 6, 9, 16, 23, 28, 37 and 46 weeks of age. The radiological appearance of the developing tarsus as evaluated from radiographs is described. During the first week postnatally, eight loci were observed to be partially ossified. The talus, tarsi centrale (Tc), first (T1), second (T2), third (T3) and fourth (T4) tarsal bones had each a single loci. The calcaneus bone had two loci, one for the tuber calcanei and another for the calcaneus himself. Fusion of the locus for T2 and T3 was evident in radiographs taken at three weeks. The fused T2 + T3 also appeared fused with the Tc in one of the goats at 23 weeks. The Tc and T4 were observed to fuse in only three of the goats at 23 weeks while in others the bones remained separate throughout the study period. In those goats where the Tc and T4 tarsal bones were not fused, the three tarsal joints were linked by a radiolucent line between these bones. While in the goat where Tc and T2 + T3 bone fusion has occurred the distal intertarsal joint was blocked and the proximal intertarsal was communicating with the tarsometatarsal joint between the separate Tc and T4. The tarsus of the goat is variable and differs from that of sheep and cattle.