山羊胎儿不同发育时期组织结构特点

Structural development characteristics of goat fetus tissues in different developmental stages

【目的】获得安徽白山羊出生前后不同时期骨骼肌、肾脏、肝脏及腿骨组织结构的发育特点,以补充山羊组织系统发育资料,丰富山羊胚胎学相关内容。【方法】安徽白山羊在同期发情及配种后,采集胚龄65 d(F65)、120 d(F120)、135 d(F135)以及出生24 h(B0)胎羊和规范饲喂90 d(B90)羔羊的骨骼肌、肾脏、肝脏及腿骨,进行石蜡切片及HE染色,运用常规电镜技术对安徽白山羊不同发育阶段各组织结构进行观察。【结果】除F135与B0外的其余时期,骨骼肌同一部位、不同发育阶段的肌纤维细胞直径以及所有时期肌纤维细胞数量和密度的变化均差异显著(P<0.05);在F120时期,初级肌纤维已完全转变为次级肌纤维。肾脏质量在除F120到F135时期外的其他时期均差异显著(P<0.05),长度在所有发育时期均差异显著(P<0.05),宽度则在除F120到F135以及F135到B0时期外的其他发育时期差异显著(P<0.05)。F65时期肾脏远曲小管和近曲小管有较为明显的区别,在F135时期具有较为清晰的肾小囊,于F65到B0时期完成了肾小体的发育。肝脏质量也在除F120到F135时期外的其他发育时期均有显著差异(P<0.05),长度在F65到F120时期及B0到B90时期变化显著(P<0.05),厚度则是在除F65到F120时期和F120到F135时期外的其他时期间存在显著差异(P<0.05)。在F65时期肝脏合胞体较多,至F135肝小叶基本形成,B0时期巨核细胞基本消失,B90时期肝细胞呈颗粒及泡沫状。股骨质量与胫骨质量均以B90时期显著高于其他时期(P<0.05),胫骨和股骨长度在每个发育阶段均存在显著差异(P<0.05)。在F120时期已经出现类似骨单位的结构,至B90时期已形成完整的骨单位。【结论】依据安徽白山羊骨骼肌肌细胞的直径、数量及密度推测,安徽白山羊肌纤维细胞从增殖到膨大的关键转折期处于胎龄65~120 d。

【Objective】 This study investigated the developmental characteristics of skeletal muscle,kidney,liver and leg bones of Anhui white goats at different stages before and after birth to supplement the phylogenetic data of goat tissues and enrich the content of goat embryology.【Method】 After estrus and breeding, skeletal muscle,kidney,liver and leg bones of Anhui white goats were collected at 65 days(F65),120 days(F120),135 days(F135),24 hours of birth(B0) and standardized feeding for 90 days(B90).After paraffin sectioning and HE staining, the structure of each tissue was observed by conventional electron microscopy.【Result】 Except the F135 and B0 groups,the skeletal muscle had significant differences in muscle fiber diameter,number and density at different developmental stages(P<0.05).The mass of kidney was significantly different at all stages except F120 to F135(P<0.05),the length was significantly different at all stages(P<0.05),and the width was significant different(P<0.05) at stages except F120 to F135 and F135 to B0.The kidney had distinct difference between distal convoluted tubule and proximal convoluted tubule in the F65 period.The F135 period had a relatively clear renal capsule,and its development was completed during the F65 to B0 period. Liver mass was also significantly different at stages except F120 to F135(P<0.05),and length was significantly changed from F65 to F120 and B0 to B90(P<0.05).The liver thickness was significantly different between stages except F65 to F120 and F120 to F135(P<0.05).There were more syncytia in F65 liver,and hepatic lobule formed in F135.Megakaryocytes disappeared in B0 liver,and liver cells appeared granules and foam in B90. Femoral mass was significantly different from F120 to B0 and B90 to other periods(P<0.05),while tibia mass at B90 was significantly different from other periods(P<0.05).The leg bones had similar structure to the bone unit during F120 period,and a complete bone unit was formed in B90.【Conclusion】 Based on diameter,number and density of skeletal muscle cells,it is speculated that the key transition period of proliferation and expansion of Anhui white goat muscle fiber cells was between F65 and F120.