适宜天津市基质栽培的番茄品种筛选

利用基质栽培技术,以番茄(Lycopersicon esculentum Mill.)为供试材料,比较了天津市常用的11个番茄品种部分农艺性状、经济性状、果实营养成分指标的差异,通过对这些指标的分析,筛选出最适宜天津市基质栽培的番茄品种。结果表明,粉皇后和傲兰6号在产量、单果重等指标中表现比较突出,适合在天津市以基质栽培方式推广应用。     

通过花药漂浮培养提高花椰菜小孢子胚胎发生率

通过花药漂浮培养,成功地诱导两个秋花椰菜基因型的小孢子胚胎发生.在液体培养基与固、液体双层培养基上,小孢子胚胎产量相仿,但后者褐色胚产生较多.在液体培养基中加入62.5mg/L的硝酸银对诱导小孢子胚胎发生效果较好.试验结果表明,采用花药漂浮培养方法可以明显提高花椰菜小孢子胚产量.     

Evidence for functional G-coupled protein receptors 43 and 120 in subcutaneous and intramuscular adipose tissue of Angus crossbred steers

We conducted 3 independent experiments to demonstrate functional G-coupled protein receptor 43 (GPR43) and GPR120 in bovine intramuscular (i.m.) and subcutaneous (s.c.) adipose tissues. We hypothesized that media volatile fatty acids and long-chain fatty acids would affect cAMP-activated protein kinase-alpha (AMPKα) protein expression and cAMP concentrations differently in i.m. and s.c. adipose tissue. Experiment 1: oleic acid (18:1n-9) decreased phosphorylated AMPKα protein (p-AMPKα) and the p-AMPKα/AMPKα protein ratio in i.m. preadipocytes, increased the p-AMPKα/AMPKα protein ratio in bovine satellite cells, and had no effect in s.c. preadipocytes. Experment 2: ex vivo explants from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers were cultured 48 hr in media containing 0.25 µM ciglitizone, 5 mM glucose, and 5 mM acetate, in the absence or the presence of 100 µM oleic acid. Oleic acid increased acetate incorporation into fatty acids and GPR43 gene expression in i.m. adipose tissue (P < 0.05), but oleic acid had no effect on fatty acid synthesis or GPR43 expression in s.c. adipose tissue. Experiment 3: fresh s.c. and i.m. adipose tissue from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers was transferred immediately to 6-well culture plates containing 3 mL of KHB/Hepes/5 mM glucose. Samples were preincubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (0, 10⁻³, 10^−2.3, and 10⁻³ M) in the absence or the presence of 100 μM oleic acid or 100 µM palmitic acid (16:0) were added to the incubation media. Acetate had no effect on forskolin-stimulated cAMP production in s.c. adipose tissue but decreased cAMP in i.m. adipose tissue (P < 0.05); this indicates a functional GPR43 receptor in i.m. adipose tissue. The combination of 10⁻² M acetate and oleic acid decrease cAMP production in s.c. adipose tissue, consistent with GPR120 receptor activity, but oleic acid and palmitic acid attenuated the depression of cAMP production caused by acetate in i.m. adipose tissue. Palmitic acid depressed cAMP production in s.c. adipose tissue, and increased cAMP production in i.m. adipose tissue (P < 0.05). Propionate had no effect on cAMP production in s.c. or i.m. adipose tissue. These results provide evidence for functional GPR43 receptors in i.m. adipose tissue and GPR120 receptors in s.c. adipose tissue, both of which would suppress lipolysis.     

改良背主动脉注射法对鸡胚发育与转基因表达效率的影响

背主动脉注射是生产转基因鸡的经典方法,该方法不需换壳培养,但壳内注射技术难度大,并且无法实时观察后期胚胎发育情况。本实验对背主动脉注射法进行了改进,将增强型绿色荧光蛋白(EGFP)腺相关病毒(Adeno-associated Virus,AAV)壳外注射至150枚HH 14~16期(Hamburger-Hamilton Stage 14~16)鸡胚背主动脉中,再进行换壳培养,继续孵化至出壳,观察和分析改良背主动脉注射法与传统背主动脉注射法和胚盘下腔注射法对发育8、14、18、21 d鸡胚存活率、孵化率以及EGFP阳性检出率的影响。结果表明:改良背主动脉注射组鸡胚存活率均高于传统背主动脉注射组与胚盘下腔注射组(P<0.05或P<0.01);改良背主动脉注射组的鸡胚孵化率(37%)高于传统背主动脉注射组(16%)与胚盘下腔注射组(28%)(P<0.01);荧光蛋白手电筒检测显示,改良背主动脉注射组鸡胚EGFP阳性率(17%)明显高于传统背主动脉注射组(13%)与胚盘下腔注射组(12%)(P<0.01)。综上,背主动脉壳外注射结合换壳培养提高了转基因鸡胚胎孵化率和EGFP阳性检出率,对提高转基因鸡效率具有重要价值。     

牦牛StAR基因克隆及其生物信息学与组织表达特性的研究

旨在克隆获得牦牛StAR基因编码序列（CDS）并进行生物信息学分析,探究其mRNA组织表达特性。本研究以屠宰场采集的成年母牦牛心、肝、脾、肺、肾、卵巢、输卵管、子宫组织（n=5）,不同年龄（胎牛、1岁、2岁）牦牛的卵巢（n=3）,不同发情周期（卵泡期、黄体期）的牦牛卵巢（n=3）,黄体期黄牛的卵巢（n=3）及实验室冻存的牦牛颗粒细胞为研究材料。以牦牛黄体期卵巢cDNA为模板,用逆转录PCR克隆StAR基因,并使用MEGA7.0和ExPASy-ProtParam等软件分析其生物信息学特性;采用实时荧光定量PCR技术分析牦牛StAR基因组织表达特性。结果发现,StAR基因CDS区长858 bp,编码285个氨基酸,StAR蛋白总体带正电荷,属于碱性亲水稳定蛋白,无跨膜结构及信号肽,主要存在于细胞质和线粒体; StAR基因具有较高的保守性,符合物种进化规律。牦牛StAR基因在卵巢表达水平最高（P<0.01）,且2岁时卵巢表达水平极显著高于胎牛和1岁龄（P<0.01）,黄体期卵巢表达水平极显著高于卵泡期（P<0.01）;黄体期黄牛卵巢中StAR基因的表达量极显著高于牦牛（P<0.01）;在颗粒细胞的体外培养过程中StAR基因表达量逐渐上升,在培养24 h时达到高峰（P<0.01）,随后显著降低。综上所述,StAR基因序列较为保守,在牦牛卵巢组织中表达最高,且表达水平随年龄与卵巢周期而变化,提示StAR基因可能参与牦牛卵巢及黄体功能相关的繁殖调控。     

花椰菜尾菜发酵饲料对保育猪生长性能、血清生化指标、小肠组织形态及经济效益的影响

为研究花椰菜尾菜发酵饲料对保育猪生长性能、血清生化指标、小肠组织形态及经济效益的影响。选取42头体重相近（11.40±1.36） kg、体况良好的40日龄保育猪,随机分为两组,每组3个重复,每个重复7头。对照组饲喂基础饲粮,试验组饲喂由80%基础饲粮和20%花椰菜尾菜发酵饲料组成的试验饲粮。试验共30 d,其中预试期8 d,正试期22 d。结果表明：与对照组相比,1）试验组保育猪的平均日采食量和平均日增重分别显著提高了16.50%和18.68%（P<0.05）,腹泻率显著降低了74.35%（P<0.05）。2）试验组保育猪十二指肠、空肠、盲肠、结肠和直肠食糜pH值分别显著降低了19.16%、11.59%、14.09%、15.95%和11.23%（P<0.05）。3）试验组血清尿素氮、白蛋白、免疫球蛋白M的含量显著升高了69.84%、5.22%、100%（P<0.05）,血清总胆固醇、谷丙转氨酶的含量分别显著降低了29.43%、60.51%（P<0.05）。4）试验组保育猪的空肠绒毛高度/隐窝深度和回肠绒毛高度分别显著升高了13.64%和11.49%（P<0.05）,空肠隐窝深度显著降低了9.56%（P<0.05）。5）试验组每头猪的增重收益、毛利润分别显著提高了30.84%和44.48%（P<0.05）,饲料成本显著降低了21.58%（P<0.05）。综上所述,饲喂花椰菜尾菜发酵饲料能够降低保育猪的腹泻率,提高保育猪的生长性能,增强其免疫性能,促进肠道发育,提高经济效益。     

A filter-assisted culture method for isolation of Treponema spp. from bovine digital dermatitis and their identification by MALDI-TOF MS

Digital dermatitis (DD) is a major infectious foot disease of cattle worldwide. Some DD stages are associated with lameness, and the disease has significant economic and animal welfare consequences. The pathogenesis of the disease is not yet fully understood, but Treponema spp. have been associated consistently with clinical cases. Isolation of these fastidious bacteria is difficult and cumbersome. We describe an improved method enabling the culturing of the 3 Treponema spp. (T. pedis, T. phagedenis, and T. medium) from bovine foot specimens derived from DD lesions, using a combination of membrane filtering and subsequent growth on selective agar media. The entire procedure from sampling to verification of individual Treponema spp. takes up to 24 d. In addition, we established a MALDI-TOF MS–based identification method to be applied for confirmation of the different Treponema spp. This scheme provides an unambiguous, simple, and straightforward identification procedure for DD-associated Treponema spp.     

Effect of dipeptide on intestinal peptide transporter 1 gene expression: An evaluation using primary cultured chicken intestinal epithelial cells

Peptide transporter 1 (PepT1) is a transporter responsible for absorbing dipeptide and tripeptide in enterocytes and is upregulated by dipeptide in mammals. It has not been certain whether intestinal PepT1 expression is responsive to dipeptides in chickens because of the lack of in vitro study using the cultured enterocytes. This study established a primary culture model of chicken intestinal epithelial cells (IECs) in two-dimensional monolayer culture using collagen gel by which the response of chicken PepT1 gene expression to dipeptide stimuli was evaluated. The cultured chicken IECs showed the epithelial-like morphology attached in a patch-manner and exhibited positive expression of cytokeratin and epithelial cadherin, specific marker proteins of epithelial cells. Moreover, the chicken IECs exhibited the gene expression of intestinal cell type-specific marker, villin1, mucin 2, and chromogranin A, suggesting that the cultured IECs were composed of enterocytes as well as goblet and enteroendocrine cells. PepT1 gene expression was significantly upregulated by synthetic dipeptide, glycyl-l-glutamine, in the cultured IECs. From the results, we herein suggested that dipeptide is a factor upregulating PepT1 gene expression in chicken IECs.     

鸡FKBP5基因的克隆、生物信息学及组织表达谱分析

本研究旨在对鸡FK506结合蛋白5(FK506 binding protein 5,FKBP5)基因进行克隆和生物信息学分析,并检测其在鸡不同组织中的表达量。以鸡脾脏cDNA为模板,通过PCR方法扩增和克隆鸡FKBP5基因完整CDS区序列,并进行同源性比对及系统进化树构建;使用在线软件分析FKBP5蛋白的理化性质、疏水性、跨膜结构、信号肽、二级结构和三级结构;利用实时荧光定量PCR检测其在肢体内外翻畸形(valgus-varus deformity,VVD)组肉鸡和正常组肉鸡组织中的表达量,并绘制组织表达谱。结果显示,鸡FKBP5基因CDS区序列全长1350 bp,编码449个氨基酸;同源性比对和进化树分析表明,鸡FKBP5基因氨基酸序列与鹌鹑、鸭、壁虎、中华鳖、小鼠、人、猪、斑马鱼的同源性分别为98.4%、96.2%、85.8%、87.4%、81.1%、85.2%、86.1%和61.2%,与鹌鹑、鸭的亲缘关系最近,爬行类和哺乳类动物次之,与斑马鱼(鱼类)亲缘关系最远。鸡FKBP5蛋白分子质量为50.43 ku,理论等电点(pI)为5.94,半衰期为30 h,肽链N端为蛋氨酸(Met),不稳定系数为23.80,属于稳定蛋白;跨膜区和信号肽预测结果显示,FKBP5蛋白不属于跨膜蛋白和分泌型蛋白。结构域分析结果表明,该蛋白包括2个FKBP型肽基脯氨酰异构酶(FKBP-type peptidylprolyl isomerases)、3个四肽重复(TPR)序列,主要包含α-螺旋(46.77%)、延伸链(12.47%)和无规则卷曲(40.76%),且该蛋白与HSPA2、PPID、STIP1、HSP90AA1和HSP90AB1等互作蛋白具有很强的相关性。实时荧光定量PCR结果显示,FKBP5基因在鸡各组织中广泛表达,其中在软骨和法氏囊中表达量较高,在发病组肉鸡组织中的表达量均高于正常组肉鸡,且在心脏、腿肌、法氏囊、胸腺、软骨中表达量差异显著(P<0.05),在脾脏中表达量差异极显著(P<0.01)。本试验结果可为肉鸡骨骼疾病及腿部健康选育提供参考。