Department of Animal Science, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University, Rehovot 76100, Israel.
J Anim Sci. 2013 Jun;91(6):2784-93. doi: 10.2527/jas.2012-5548. Epub 2013 Mar 18.
The objective of this study was to examine the effect of embryonic nutritional enrichment on the development and properties of broiler leg bones (tibia and femur) from the prenatal period until maturity. To accomplish the objective, 300 eggs were divided into 2 groups: a noninjected group (control) and a group injected in ovo with a solution containing minerals, vitamins, and carbohydrates (enriched). Tibia and femur from both legs were harvested from chicks on embryonic days 19 (E19) and 21 (E21) and d 3, 7, 14, 28, and 54 posthatch (n = 8). The bones were mechanically tested (stiffness, maximal load, and work to fracture) and scanned in a micro-computed tomography (μCT) scanner to examine the structural properties of the cortical [cortical area, medullary area, cortical thickness, and maximal moment of inertia (Imax)] and trabecular (bone volume percent, trabecular thickness, and trabecular number) areas. To examine bone mineralization, bone mineral density (BMD) of the cortical area was obtained from the μCT scans, and bones were analyzed for the ash and mineral content. The results showed improved mechanical properties of the enriched group between E19 and d 3 and on d 14 (P < 0.05). Differences in cortical morphology were noted between E19 and d 14 as the enriched group had greater medullary area on E19 (femur), reduced medullary area on E21 (both bones), greater femoral cortical area on d 3, and greater Imax of both bones on d 14 (P < 0.05). The major differences in bone trabecular architecture were that the enriched group had greater bone volume percent and trabecular thickness in the tibia on d 7 and the femur on d 28 (P < 0.05). The pattern of mineralization between E19 and d 54 showed improved mineralization in the enriched group on E19 whereas on d 3 and 7, the control group showed a mineralization advantage, and on d 28 and 54, the enriched group showed again greater mineralization (P < 0.05). In summary, this study demonstrated that in ovo enrichment affects multiple bone properties pre- and postnatally and showed that avian embryos are a good model for studying the effect of embryonic nutrition on natal and postnatal development. Most importantly, the enrichment led to improved mechanical properties until d 14 (roughly third of the lifespan of the bird), a big advantage for the young broiler. Additionally, the improved mineralization and trabecular architecture on d 28 and 54 indicate a potential long-term effect of altering embryonic nutrition.
本研究旨在探讨胚胎期营养富集对肉鸡腿骨（胫骨和股骨）从产前到成熟发育和特性的影响。为了实现这一目标，将 300 个鸡蛋分为两组：非注射组（对照组）和胚胎期注射含有矿物质、维生素和碳水化合物的溶液组（富集组）。在胚胎第 19 天（E19）和第 21 天（E21）以及孵化后第 3、7、14、28 和 54 天（n=8），从雏鸡的两条腿上采集胫骨和股骨。对骨骼进行力学测试（刚度、最大载荷和断裂功），并在微计算机断层扫描（μCT）扫描仪中进行扫描，以检查皮质[皮质面积、髓腔面积、皮质厚度和最大转动惯量（Imax）]和小梁[骨体积分数、小梁厚度和小梁数量]区域的结构特性。为了检查骨矿化情况，从 μCT 扫描中获得皮质区域的骨矿物质密度（BMD），并分析骨骼的灰分和矿物质含量。结果表明，富集组在 E19 和 d3 之间以及 d14 时具有更好的力学性能（P<0.05）。在 E19 和 d14 之间观察到皮质形态的差异，因为富集组在 E19 时具有更大的髓腔面积（股骨），在 E21 时具有更小的髓腔面积（两个骨骼），在 d3 时具有更大的股骨皮质面积，在 d14 时具有更大的两个骨骼的 Imax（P<0.05）。骨小梁结构的主要差异在于，在 d7 时，富集组的胫骨和 d28 时的股骨的骨体积分数和小梁厚度较大（P<0.05）。从 E19 到 d54 的矿化模式表明，在 E19 时，富集组的矿化情况得到改善，而在 d3 和 d7 时，对照组具有矿化优势，在 d28 和 d54 时，富集组再次表现出更大的矿化（P<0.05）。总之，本研究表明，胚胎期的营养富集会影响产前和产后的多种骨骼特性，并表明禽类胚胎是研究胚胎营养对出生和产后发育影响的良好模型。最重要的是，这种富集导致在 d14 之前（大约是鸡的寿命的三分之一）力学性能得到改善，这对幼鸡来说是一个很大的优势。此外，在 d28 和 d54 时改善的矿化和小梁结构表明，改变胚胎营养可能具有长期影响。
