Hurwitz S, Livne E, Plavnik I, Pines M, Silberman M
Institute of Animal Science, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel.
Growth Dev Aging. 1992 Winter;56(4):191-203.
Tibia development was studied by histomorphometry in male chickens and turkeys fed ad libitum throughout the growing period, or subjected to an early-age (1-week) severe feed restriction for 6 and 14 days, respectively. In turkeys, the rates of longitudinal bone growth and epiphyseal width growth, both dependent on the activity of chondrocytes, proceeded rapidly and reached maxima at early ages of 24 and 11 days, respectively. Moreover, longitudinal bone growth and the growth of epiphyseal width were reduced during early-age feed restriction, in both chickens and turkeys. On the other hand, the rate of growth of metaphyseal width, determined by activity of bone cells such as osteoclasts and osteoblasts, reached in turkeys a maximum at the relatively late age of 70 days, and was not influenced by feed restriction. Rhythmic variation characterized the temporal behavior of the height of the hypertrophic and non-hypertrophic zones of the growth plate, the trabecular width, and the osteoclasts number at the subchondral region. Rhythmicity appeared similar in both ad libitum-fed and early-age feed-restricted birds of both species. The height of the non-hypertrophic epiphyseal cartilage appeared not to change, whereas the hypertrophic zone decreased with age and early-age feed restriction, demonstrating the importance of cartilage cell hypertrophy as a main determinant of longitudinal bone growth. Sexual maturation was accompanied by the disappearance of both hypertrophic and non-hypertrophic zones of the epiphyseal growth plate and the end of bone elongation. Trabecular width at the end of bone elongation. Trabecular width at the subchondral region increased while osteoclast number decreased with age, reflecting the net increase in bone mass, but were not affected significantly by early age feed restriction. Compensatory growth of the early-age feed-restricted birds, resulted in the complete recovery of affected bone variables within a few weeks of resumed ad libitum feed intake.
通过组织形态计量学研究了雄性鸡和火鸡的胫骨发育情况，这些鸡和火鸡在整个生长期间自由采食，或者分别在早期（1周龄）进行6天和14天的严重限饲。在火鸡中，纵向骨生长速率和骨骺宽度生长速率均依赖于软骨细胞的活性，二者分别在24天和11天的早期迅速进行并达到最大值。此外，在鸡和火鸡中，早期限饲期间纵向骨生长和骨骺宽度生长均降低。另一方面，由破骨细胞和成骨细胞等骨细胞活性决定的干骺端宽度生长速率，在火鸡中在相对较晚的70天达到最大值，且不受限饲影响。生长板肥大和非肥大区域的高度、小梁宽度以及软骨下区域破骨细胞数量的时间行为具有节律性变化。在两个物种中自由采食和早期限饲的鸟类中，节律性似乎相似。非肥大性骨骺软骨的高度似乎没有变化，而肥大区域随年龄和早期限饲而减小，这表明软骨细胞肥大作为纵向骨生长的主要决定因素的重要性。性成熟伴随着骨骺生长板肥大和非肥大区域的消失以及骨伸长的结束。骨伸长结束时的小梁宽度。软骨下区域的小梁宽度随年龄增加而增加，破骨细胞数量随年龄减少，反映了骨量的净增加，但不受早期限饲的显著影响。早期限饲鸟类的代偿性生长导致在恢复自由采食几周内受影响的骨变量完全恢复。
