蛋黄油的提取及其氧化产物挥发性成分分析

为提高淘汰蛋鸡副产物——卵泡的利用率,本研究以鸡卵泡为试验原料,经提取卵磷脂、脱去胆固醇后,将其卵泡残渣以溶剂萃取法提取出蛋黄油,通过单因素试验和正交试验研究了提取温度、提取时间、料液比和乙醇浓度对蛋黄油提取的影响。之后将提取的蛋黄油进行氧化调控,采用气相离子迁移色谱(GC-IMS)进行测定与分析。正交试验结果表明,鸡卵泡中蛋黄油提取的最佳工艺条件:提取温度80℃,提取时间55 min,料液比1∶10,乙醇浓度95%。氧化蛋黄油中含有多种挥发性物质,包括4种醇类、3种醛类、2种酯类、2种酮类、1种呋喃,其中3-甲基丁醛是氧化蛋黄油的特征风味物质。本研究结果为开发利用蛋鸡副产物,提高产品附加值提供了新思路。     

云南半细毛羊毛囊干细胞表面标记物的鉴定

设计8对引物（CK14、CK15、CK19、CD34、CD271、CD200、nestin和β1）,分别扩增云南半细毛羊成纤维细胞和毛囊干细胞表面标记物.结果表明：在成纤维细胞中CK19和β1表现为阳性,而在毛囊干细胞中CK14、CK19和β1表现为阳性,其他标记物的表达都为阴性.因此,CK14可以作为鉴定云南半细毛羊毛囊干细胞的表面标记物之一.     

基于高通量测序的山羊卵巢基质、卵泡转录组分析

【目的】比较山羊Capra hircus卵巢基质、大卵泡和小卵泡间的m RNA表达图谱,为探究卵泡发育机制提供一定的研究基础。【方法】采用高通量测序技术对发情期川中黑山羊的卵巢基质、大卵泡和小卵泡进行转录组测序,利用生物信息学方法检测mRNA表达谱,筛选差异基因,对其进行GO和KEGG通路分析,最后随机抽取5个差异基因进行荧光定量PCR验证。【结果】卵巢基质vs大卵泡、卵巢基质vs小卵泡和小卵泡vs大卵泡的差异表达基因分别为524、180和403个。筛选出INHA、TNFRSF19等15个与卵泡发育相关的基因,其主要富集在内质网蛋白质加工、类固醇生物合成、卵母细胞减数分裂等信号通路。通过q RT-PCR验证,定量结果与测序结果基本一致。【结论】川中黑山羊卵巢基质、大卵泡和小卵泡的基因表达模式不同,小卵泡与卵巢基质的基因表达模式更相近。     

Relationship among ovarian follicular status,developmental competence of oocytes,and anti‐Müllerian hormone levels: A comparative study in Japanese wild boar crossbred gilts and Large White gilts

The aim of this study was to investigate the ovarian follicular development, developmental competence of oocytes, and plasma anti‐Müllerian hormone (AMH) levels of Japanese wild boar crossbred (wild hybrid) gilts, whose litter size is inferior to that of European breeds. Ovary and plasma samples were collected from two different breeds of gilts (wild hybrid and Large White breeds). The ovaries from the wild hybrid gilts had a lower average numbers of secondary follicles and vesicular follicles in ovarian cross‐sections and of good quality oocytes collected from ovarian follicles as compared with those from Large White gilts (p < 0.05). The development rate to the blastocyst stage of good quality oocytes after in vitro maturation, fertilization and culture was also lower (p < 0.05) in wild hybrid gilts than in Large White gilts. Plasma AMH levels with >0.16 ng/ml were detected in 8.3% of the examined wild hybrid gilts and 33% of the Large White gilts. These results indicate that the low reproductive performance of wild hybrid breed may result in part from low numbers of vesicular follicles and good quality oocytes, and low developmental competence of oocytes. Moreover, plasma AMH levels may support low number of vesicular follicles in ovaries of wild hybrid gilts.     

Effect of oxygen tension on in vitro viability and development of dog follicles enclosed within the ovarian cortex

Oxygen concentration has been shown to influence in vitro viability and growth of ovarian follicles. The present study examined the effect of oxygen tension on in vitro development of dog follicles enclosed within the ovarian cortex. Ovaries were obtained from domestic dogs (age, 8 months to 2 years), and cortical fragments were recovered. The cortices were then incubated on 1.5% (w/v) agarose gel blocks within a 4‐well culture plate containing Eagle Minimum Essential Medium (MEM). Ovarian follicles within the tissues were processed for histology and assessed for follicle density, viability and diameter immediately after collection (Control) or after 2 or 5 days of in vitro incubation. Apoptotic cells were assessed using TUNEL assay. Comparisons of follicular viability and diameter were performed using analysis of variance followed by Tukey's test (p < 0.05). Comparisons of follicle density and apoptosis among treatments were conducted using Non‐parametric Kruskal–Wallis test followed by Friedman's test (p < 0.05). No difference (p > 0.05) in follicle density was observed among groups at Day 2 of in vitro culture. However, the density of follicles within cortices cultured in 20% oxygen for 5 days significantly reduced compared to the Control and those incubated in 5% concentration. The viability of cultured follicles in all treatments decreased (p < 0.05) compared to the Control after 2 days incubation, and this value further reduced (p < 0.05) in 20% oxygen group at Day 5. There were no differences in the percentages of apoptotic follicles between the two treatment groups (p > 0.05). Nevertheless, after 5 days of culture, the percentage of TUNEL‐positive follicles increased significantly (p < 0.05) in cortices incubated in 20% oxygen environment. In conclusion, our findings demonstrated that 5% oxygen level was superior to 20% concentration in sustaining in vitro viability of dog follicles enclosed within the ovarian cortex.     

Relationship of the conception rate and the side (left or right) of preovulatory follicle location at artificial insemination in dairy heifers

In this study, we examined the locational effect (left or right ovary) of the preovulatory follicle (PF) on fertility in dairy heifers. In total, 1,111 artificial inseminations (AI) were analyzed. At AI, PF locations were examined using rectal palpation, and heifers were divided into two groups on their PF locations: (i) the PF located in the left ovary (L‐PF); and (ii) the PF located in the right ovary (R‐PF). Pregnancy was diagnosed by rectal palpation 60 days after AI. The conception rate was 50.7% in all heifers. Conception rate was significantly higher in the L‐PF (60.1%) than in the R‐PF (46.2%). The conception rate was significantly lower by sexed semen (48.6%) than conventional semen (59.1%). Conception rates divided by the semen type (sexed: n = 896, conventional: n = 215) were significantly higher in the L‐PF than in the R‐PF for both semen types (sexed; L‐PF vs. R‐PF: 57.3% vs. 44.4%, conventional; L‐PF vs. R‐PF: 72.3% vs. 53.3%). In addition, season, age, AI number, and the number of re‐inseminations at the same estrus did not affect conception rates. In summary, PF development in the left ovary was associated with increased conception rates in dairy heifers.     

VEGF对绵羊卵泡颗粒细胞FSHR、E2R表达的影响

血管内皮生长因子(VEGF)可以促进颗粒细胞的增殖,但是否影响同样分布于颗粒细胞上的FSHR、E2R表达效果尚属未知.因此,通过Western blotting和荧光定量PCR分别对添加0、5、10、15、20、25 μg/L VEGF卵泡颗粒细胞中FSHR、E2R表达量及FSHR mRNA、E2R mRNA表达量进行检测.Western blotting蛋白检测结果表明,空白对照组和各个不同质量浓度VEGF处理组的颗粒细胞上均有FSHR和E2R蛋白表达,FSHR相对分子质量为75 000,E2R相对分子质量为56 000；荧光定量PCR检测结果表明,添加VEGF的各个处理组中FSHR mR-NA、E2R mRNA表达量均显著高于对照组(P＜0.05),各处理组间的FSHR mRNA之间差异不显著(P＞0.05),而VEGF添加量20、25 μg/L组的E2R mRNA表达量显著高于其他3个处理组(P＜0.05),并且这2个组间则差异不显著(P＞0.05),其余3个处理组间亦差异不显著(P＞0.05).     

反刍家畜卵泡发育机理的研究进展

反刍动物的卵泡发育是一个复杂且高度协调的过程，最新的研究肯定了卵泡发育以波的形式存在，但在影响卵泡发育的因素中，除了传统的下丘脑—垂体—性腺轴外，一些非促性腺激素内源性因子及卵巢内部因子也起到非常重要的作用，即便如此，要想对反刍动物卵泡发育进行更精确的控制，仍需作更进一步的研究     

卵泡中胆固醇脱除技术研究

为提高淘汰蛋鸡副产物的利用率及品质,采用β-环状糊精(β-CD)包合法脱除其中的胆固醇。结果表明:通过正交试验优化出的脱除工艺可以有效降低卵泡中的胆固醇含量,即将卵泡醇提物与15%的β-CD以1∶1的料液比混合,30 ℃搅拌40 min,卵泡中的胆固醇脱除率达到76.81%,保留的磷脂成分占干基质量的22.4%。     

AREG对绵羊小腔卵泡卵母细胞体外成熟的影响

旨在研究双调蛋白（AREG）对绵羊小腔卵泡卵母细胞体外成熟（IVM）的影响。本研究从屠宰场绵羊卵巢上采集小腔和中腔卵泡的卵母细胞进行试验，利用自发荧光检测卵母细胞的NAD （P） H和FAD⁺⁺水平，利用JC-1检测卵母细胞的线粒体膜电位；两种来源的卵母细胞经体外成熟后，比较其卵丘扩展指数（CEI）、第一极体排出率（MII%）；比较AREG、AREG+GDF9、AREG+BMP15、AREG+GDF9+BMP15、GDF9+BMP15对小腔卵泡卵母细胞体外成熟后的CEI、MII%及卵母细胞线粒体膜电位的影响；检测了AREG+GDF9+BMP15对小腔卵泡卵母细胞体外成熟后的NAD （P） H和FAD⁺⁺水平及其受精后发育能力的影响。结果表明，成熟前，小腔卵泡卵母细胞的线粒体膜电位和FAD⁺⁺水平均显著低于中腔卵泡卵母细胞（P<0.05）；体外成熟培养后，小腔卵泡卵母细胞的CEI和MII%均显著低于中腔卵泡卵母细胞（P<0.05）。与对照组相比，AREG+GDF9+BMP15显著提高了小腔卵泡卵母细胞体外成熟后的CEI、MII%和线粒体膜电位（P<0.05），且与中腔卵泡卵母细胞组差异不显著（P>0.05）；另外，AREG+GDF9+BMP15显著提高了小腔卵泡卵母细胞体外成熟后的NAD （P） H和FAD⁺⁺水平（P<0.05），且与中腔卵泡卵母细胞组差异不显著（P>0.05）。与对照组相比，在成熟液中添加AREG+GDF9+BMP15可以明显提高小腔卵泡卵母细胞体外受精后的卵裂率和囊胚率（分别为（43.79±3.69）%、（28.54±4.31）%和（78.99±1.12）%、（47.46±2.50）%，P<0.05），而且与中腔卵泡卵母细胞组无显著差异（P>0.05）。综上表明，绵羊小腔卵泡卵母细胞的代谢水平及IVM质量较低， AREG在GDF9和BMP15的协同作用下可以显著提高小腔卵泡卵母细胞的代谢水平及IVM质量，并进一步提高小腔卵泡卵母细胞体外受精后的发育能力。