Histological Characteristics of Adult Yak Epididymis in Different Breeding Seasons

To compare the histological changes of the adult yak's epididymis in different breeding seasons,six adult yak testis in breeding season and nine adult yak testis in breeding interval were collected for structure investigation by HE staining,Masson's and Gomori's histochemistry methods,and IPP (Image-Pro Plus) statistics method was used to quantitative statistics.The results showed that comparing with the adult yak in the breeding interval,the epididymis ducts of adult yak in the breeding season were covered with the columnar ciliated epithelium.The collagen and reticular fiber in cauda epididymis were obviously more abundant than caput and corpus epididymitis.And the thickness of columnar epithelium cells in caput and corpus epididymitis,the length of the cilia in caput,and also the internal and external lumen diameter of caput and corpus epididymitis were all significantly increased in the breeding season (P<0.05),but the external lumen diameter of the cauda epididymis had no significant differences (P>0.05).In conclusion,the research showed that the distribution of collagen and reticular fiber in adult yak's epididymis interstitial were similar,and they were more rich in cauda epididymis,which might relate to the capacity and the sperm transport;The changes of the epithelial thickness,the length of cilia,the internal and external lumen diameter were close related to the different breeding seasons,and it might be a common phenomenon in plateau mammals that the enlargement and reduction of the epididymal duct in different breeding seasons.     

Effects of Dietary Geniposide on Growth,Flesh Quality,and Lipid Metabolism of Grass Carp,Ctenopharyngodon idella

The aim of this study was to investigate effects of dietary geniposide (GP) on growth performance, flesh quality, and lipid metabolism of grass carp, Ctenopharyngodon idella (95.2 ± 0.6 g), fed seven different diets, including a control diet; Eucommia ulmoides (EU)–supplemented diet (20 g/kg); and GP‐supplemented diets containing 100, 200, 400, 600, and 800 mg/kg GP, respectively. Weight gain rate was significantly improved (P < 0.05) and feed conversation ratio was significantly decreased (P < 0.05) by supplementation of EU. Grass carp fed 100–800 mg/kg GP‐supplemented diets showed significantly higher total collagen and alkaline‐insoluble collagen content in muscle than control (P < 0.05). Contents of total collagen and the alkaline‐insoluble collagen content in the skin of grass carp were significantly increased by dietary 600–800 mg/kg GP and EU (P < 0.05). Fish fed diets containing 600–800 mg/kg GP showed significantly lower muscle crude lipid content than the EU, control, and 100–400 mg/kg GP groups (P < 0.05). Fish fed 400–800 mg/kg GP diets had significantly higher muscle fiber density and lower muscle fiber diameter and serum triglyceride level than the control (P < 0.05). In conclusion, supplementation of GP could improve flesh quality, but not growth of grass carp. The supplemental level of GP for improving flesh quality was estimated to be a 400–600 mg/kg diet.     

大通牦牛骨骼肌胶原纤维含量增龄性变化特点

为探讨高原牦牛随着年龄的增长,骨骼肌中胶原纤维含量的变化规律及其对高原低氧环境的适应性。本研究以不同生长期大通牦牛作为研究对象,并以平原黄牛作对照,对生长发育过程骨骼肌中胶原纤维含量变化进行测量。结果表明,大通牦牛骨骼肌中胶原纤维含量从1日龄的一个相对低点,到30日龄迅速增长至一个峰值,然后再逐渐下降,至成年时,胶原纤维含量降至最低。平原黄牛骨骼肌中胶原纤维含量1日龄处于峰值,与其他年龄组差异显著(P<0.05),而随着年龄的增长,胶原纤维含量下降,30日龄、180日龄和成年组差异不显著(P>0.05);相同发育阶段大通牦牛骨骼肌中胶原纤维含量均高于平原黄牛胶原纤维含量,且差异显著(P<0.05)。结果提示,大通牦牛骨骼肌中胶原纤维具有适应高原环境的组织学特点,但也在个体发育过程中,不断发生改变,以满足机体生长发育的需要和对外界环境的适应。     

水产动物胶原蛋白研究现状及发展前景

胶原蛋白是生物体内的一种重要蛋白质，水产胶原蛋白是其中一种。水产胶原蛋白比陆生动物胶原蛋白的安全性更高，同时水产胶原蛋白具有优良的理化特性和生理活性功能。对水产胶原蛋白的研究现状、开发优势及前景进行综述。     

Structural remodelling of the heart valves extracellular matrix during embryo development

Alterations in heart valve development represent more than 20% of congenital cardiovascular malformations. Most of the functional properties of heart valves depend on extracellular matrix. Despite its relevance, little is known about fibrillar components on developing stages. Our objective is to define histological changes on valves fibrillar components in late embryonic development of Mus musculus. We found type III collagen as the predominant fibre type in the ECM in prenatal stages followed by a switch to a type I predominance for postnatal ages. The change in fibrillar components is necessary to support the normal mechanical function of adult heart valves.     

鱿鱼皮胶原蛋白提取前处理的条件优化

试验测定了鱿鱼皮的基本组成成分,探索了酶法提取鱿鱼皮胶原蛋白时前处理的最佳条件。选定了4个因素3,个水平,采用L9(34)正交试验确定了最佳条件。结果表明4,个因素NaOH浓度,NaOH作用时间、异丙醇浓度、活性炭浓度的最佳选择分别为0.15 mol/l、6 h、12%、0.8%,此时提取的胶原蛋白含量为11.08%,提取率为93.6%。     

牛输卵管上皮细胞转人胶原蛋白cDNA基因及转基因克隆胚胎

以2岁奶牛输卵管为材料,用胰酶消化法分离得到了牛输卵管上皮细胞。输卵管上皮细胞在DMEM／F12培养基中生长良好。用一代牛输卵管上皮细胞为靶细胞,对其进行了电穿孔转染,转染对象是分子大小为31085bp的以β-casein启动子为基础的含有人胶原蛋白cDNA基因和EGFP、Neor双标记基因的质粒。电穿孔试验发现,牛输卵管上皮细胞在低渗缓冲液中电转染可以获得阳性转染子,其中以90mOsm／kg为最佳。电压以800V为好,电压高和低都不利于电穿孔的成功。成功转染的细胞用800mg/L G418进行筛选,在10d后获得了较大的阳性细胞克隆簇。对获得的阳性细胞克隆簇进行扩大后,得到了较纯的阳性细胞克隆系,流式细胞仪检测其纯度为81．6％。在荧光显微镜下选择阳性细胞作为核移植供体细胞进行了转基因克隆试验,结果显示以转基因和非转基因细胞为核供体获得的重构胚融合率差异显著（51．9％比63．2％）,获得的桑椹胚／囊胚率差异不显著（20．3％比25．5％）。对获得的具有绿色荧光的胚胎进行DNA分析,结果显示这些胚胎成功转入了外源基因,并且转入的外源基因结构完整。     

Changes in collagen fiber content and hepatic stellate cell distribution in the liver of chick embryos and growing chickens

The content of collagen and the distribution of hepatic stellate cells (HSCs) were studied to elucidate the occurrence of sex‐dependent variations in the liver of developing embryos and growing chickens. Chick embryos from embryonic days (e) 12 to e20 and chicks at 1, 4 and 8 weeks were analyzed. Liver tissue was processed using NaOH maceration and freeze‐dried to obtain the collagen fiber specimens. HSCs were identified by double fluorescent immunohistochemistry for desmin and vimentin. There were no sex‐dependent variations in the percentage of collagen fiber per liver weight and HSC area during embryonic stages. However, the content of collagen fiber increased during embryonic development in both sexes. On the other hand, the area of HSCs significantly increased in growing males but did not show any change in females. Importantly, sex differences were observed in both collagen fiber content and HSC area in the liver at 8 weeks. These results indicate that the occurrence of collagen content variations takes place at 8 weeks in chicken liver, suggesting that a sex‐dependent hormone may play an important role on the collagen production of HSCs in the growing chicken liver.     

麦洼牦牛初乳期乳腺中2个特异表达EST片段的克隆与分析

为研究牦牛初乳期乳腺特异表达的基因,采用抑制消减杂交和斑点杂交法对麦洼牦牛初乳期(产犊后2 d)和常乳期(产犊后18 d)特异表达的基因进行了分离鉴定。结果发现2个在初乳期间特异表达的EST片段,并命名为LAO和COL1α1。测序结果LAO片段长698 bp,GenBank比对,其核苷酸序列与西藏黄牛(Bos taurus)、小家鼠(Mus musculus)、家犬(Canis familiaris)等的L-氨基酸氧化酶基因有较高的序列相似性,其序列一致性分别达到96%、73%、72%;COL1α1片段长337 bp,比对结果,其序列与Bos taurus、马鹿(Cervus elaphus)、家犬(Canis lupus fa-miliaris)等的Ⅰ型胶原蛋白α1有较高的序列相似性,其序列一致性分别为100%、100%、99%。2个序列与牛基因组的Blast分析表明,LAO片段定位于3号染色体LOC782545区,该区域编码1个L-氨基酸氧化酶基因;另一片段定位于19号染色体LOC615867区,该区域编码1个Ⅰ型胶原α1基因。研究表明,L-氨基酸氧化酶基因和Ⅰ型胶原蛋白α1基因是牦牛初乳期乳腺特异表达蛋白,这2个基因在牦牛初乳期乳腺组织中较高的表达水平可能与初乳期乳腺特殊的生理状态有关。