基于液质联用技术的卵巢静止奶牛血浆代谢轮廓分析

旨在应用代谢组学技术筛选产后卵巢静止奶牛血浆中差异代谢物,探究差异代谢物与奶牛卵巢静止的关系。试验选取了产后45～60 d卵巢静止奶牛和正常发情奶牛各15头,应用LC/MS技术检测两组奶牛血浆样品,运用多元统计分析与单变量分析,结合生物信息学分析,筛选出血浆差异代谢物,揭示不同代谢通路中的差异代谢物与奶牛卵巢静止的关系。结果显示:LC/MS分析共筛选出14种血浆差异代谢物。与发情组奶牛相比,卵巢静止组奶牛有11种差异代谢物明显升高:分别是D-塔格糖、L-亮氨酰-L-脯氨酸、L-鹅肌肽、脯氨酸-缬氨酸、赖氨酸-亮氨酸、N-(3-苯基丙酰基)甘氨酸、7-烯胆(甾)烷醇、γ-生育酚、β-隐黄素、视黄醛和鞘磷脂;3种差异代谢物降低:分别是胞嘧啶、1-棕榈酰溶血磷脂酰胆碱和1-硬脂酰-SN-甘油-3-磷酰胆碱。代谢通路分析代谢组学所获得的奶牛卵巢静止血浆差异代谢物,提示奶牛产后糖代谢、脂类代谢、氨基酸代谢和谷胱甘肽代谢等的异常会阻碍卵泡发育,从而导致奶牛产后发生卵巢静止。本试验获得了卵巢静止奶牛血浆差异代谢物,探究了奶牛产后卵巢静止发生中差异代谢物在糖代谢、脂代谢和氨基酸代谢以及其他代谢的变化,为今后深入研究奶牛卵巢静止的发病机理及防治新策略提供了方向。     

基于核磁共振技术的卵巢静止奶牛血浆代谢谱分析

为研究卵巢静止奶牛与发情奶牛体内差异代谢物变化,选取产后60~90d的年龄、胎次、体况相近的健康经产高产奶牛作为实验动物。根据奶牛发情表现、直肠检查和B超检查及激素检测的结果,选取10头奶牛为发情组(A),10头奶牛为卵巢静止组(B),然后对两组奶牛血浆样品进行无偏性的1 H谱核磁共振检测,对比其血浆代谢组学图谱,进行多元统计分析,筛选及鉴定卵巢静止奶牛血浆差异代谢产物,并进行生物信息学分析。结果显示:相对于正常发情奶牛,卵巢静止奶牛血浆中共12种代谢产物表现异常,包括水平增加的乙酸、柠檬酸和酪氨酸,以及水平下降的低密度脂蛋白、极低密度脂蛋白、脂质、丙氨酸、丙酮酸、肌酸、胆碱、磷酸胆碱和甘油磷酸胆碱等;这些代谢产物与糖代谢、氨基酸代谢、脂蛋白代谢和胆碱代谢的异常密切相关;通过参与生物合成通路调节,干扰了奶牛正常卵泡生长。并且发现卵巢静止的奶牛血浆肌酸浓度降低和酪氨酸浓度升高的新变化。多种代谢异常提示奶牛卵巢静止与泌乳早期能量负平衡有关,并有伴发酮病和脂肪肝病的风险;另外,卵巢静止奶牛血浆肌酸、胆碱浓度降低和酪氨酸浓度升高的变化,为今后更为深入研究奶牛卵巢静止发生机制提供了新的方向。     

基于~1H-NMR技术的产后卵巢静止奶牛乳清和血清代谢谱分析

旨在应用代谢组学技术筛选产后卵巢静止奶牛乳清和血清的差异代谢物,明确其与奶牛卵巢静止的关系。本研究选取产后45～60 d的正常发情奶牛和卵巢静止奶牛各14头进行试验。应用一维氢谱核磁共振(~1H-NMR)技术对两组奶牛的乳清和血清进行检测,结合多元统计分析和单变量分析,筛选出组间差异代谢物,并进行生物信息学分析,阐明差异代谢物参与的代谢通路与奶牛卵巢静止的关系。结果表明,在乳清和血清中分别筛选出13种差异代谢物。与发情奶牛相比,卵巢静止奶牛乳清中6种差异代谢物含量升高:琥珀酸、磷酸肌酸、甘氨酸、肌醇、乙醇酸、乳清酸,7种下降:丙氨酸、肌酐、磷酸胆碱、乳糖、牛磺酸、半乳糖、葡萄糖-1-磷酸;血清中4种差异代谢物升高:β-羟丁酸、乙酸、谷氨酰胺、甘氨酸,9种降低:丙氨酸、琥珀酸、柠檬酸、肌酐、磷酸胆碱、葡萄糖、肌醇、酪氨酸、组氨酸。两组奶牛乳清差异代谢物主要参与牛磺酸和亚牛磺酸代谢、半乳糖代谢、原代胆汁酸生物合成等。血清差异代谢物主要参与丙氨酸、天冬氨酸和谷氨酸代谢、乙醛酸和二羧酸代谢、柠檬酸循环、苯丙氨酸、酪氨酸和色氨酸生物合成等。本研究获得了卵巢静止奶牛乳清和血清的代谢谱及其差异代谢物,结果表明了主要的糖代谢、脂代谢和氨基酸代谢的异常途径在奶牛产后卵巢静止发生中所起的作用,为今后深入研究奶牛产后卵巢静止发生机制和防治策略提供了新的方向。     

奶牛亚临床低血钙症的蛋白质组学分析

根据奶牛血浆钙浓度将奶牛分为试验组和对照组,并设置2个平行试验组。应用iTRAQ/LC-MS/MS技术对2组奶牛样品进行差异表达蛋白的筛选和鉴定,并结合生物信息学软件对试验结果进行分析。试验共得到398个差异表达蛋白,其中2个平行试验组重叠的蛋白为265个,经过筛选共得到14种具有统计学差异的表达蛋白。结合生物信息学分析中的基因功能分析,结果得到74个注释结果,细胞组成、分子功能和生物过程分别为6,12,55个。根据结果分析可知,奶牛亚临床低血钙症生理和病理现象能够从3个方面解释其生理和病理现象,分别是血钙调节、免疫与炎症反应和血液凝固与补体途径。本试验首次应用iTRAQ结合LC-MS/MS技术对亚临床低血钙症奶牛进行蛋白质组学分析,填补该技术对亚临床低血钙症的空白,并提供科学依据。     

绵羊超数排卵卵巢差异表达基因及生物信息学分析

【目的】筛选出影响经超数排卵处理的多浪羊卵巢卵泡发育的关键基因、生物过程及信号通路,为进一步了解多浪羊超数排卵状态下卵巢生长发育机制提供依据。【方法】对15只2～3岁身体状况良好的多浪羊进行超数排卵处理后,采集超数排卵中早期(第11天)、中期(第13天)、晚期(第15天)卵巢组织,利用高通量测序技术进行转录组测序,将测序得到的reads序列与参考基因组进行序列比对,筛选出差异表达基因;通过STRING数据库对差异表达基因进行蛋白互作网络分析,采用Cytoscape软件进行可视化编辑处理,利用eggNOG-mapper软件进行GO功能和KEGG通路富集分析。【结果】超数排卵卵巢第11和13天共筛选出223个差异表达基因,获得259条互作关系,差异表达基因显著注释在细胞生长、核糖核蛋白复合等条目中,其中显著差异表达的基因为ITGB3和SNAI1,未发现显著富集通路。超数排卵卵巢第13和15天共筛选出694个差异表达基因,获得785条互作关系,差异表达基因显著注释在DNA复制的启动、DNA复制、DNA新陈代谢过程等条目中,其中显著差异表达的基因主要有CASP3、NOTCH1、WNT2和RUN...     

中药组方“暖宫散”、“气血通”治疗奶牛卵巢性不孕症试验

在影响奶牛繁殖的诸多因素中,卵巢疾病性不孕导致奶牛发情周期异常、繁殖性能低下,是引起奶牛不孕的重要原因之一,包括卵巢机能减退（卵巢静止）、持久黄体、卵巢囊肿、卵泡交替发育、排卵延迟等多种疾病。笔者应用自拟组方治疗奶牛卵巢静止、持久黄体和卵巢囊肿等卵巢性不孕症71例,平均发情率为94.4%,受孕率为81.7%。     

奶牛卵巢疾病的诊断与治疗

乾安县是畜牧业养殖大县,养殖业发展迅速,近几年奶牛的养殖量逐渐递增,在奶牛养殖业发展高势头的前提下,奶牛的疾病也随之而来,特别是奶牛卵巢疾病的发病率不断升高,卵巢疾病是造成奶牛不孕的重要原因,奶牛卵巢疾病主要包括卵巢囊肿（卵泡囊肿、黄体囊肿）、卵巢静止和持久黄体,这几种病主要的临床症状都是发情异常,也就是不发情或持久发情,根据多年的工作经验现将奶牛卵巢疾病几个典型病例的诊断与治疗报告如下,供同行们参考。     

影响奶牛配种准胎率的繁殖疾病

1奶牛卵巢疾病 　　奶牛卵巢疾病主要有卵巢机能减退、卵巢囊肿和持久性黄体等. 　　1.1卵巢机能减退 　　包括卵巢机能不全、卵巢静止和卵巢萎缩.卵巢机能不全,病牛发情正常,发情明显或微弱,卵巢中有成熟卵泡,但不排卵;直肠检查,卵巢无特殊变化.卵巢静止,母牛不发情,卵巢大小、质地正常;直肠检查,卵巢上无卵泡和黄体,其体积变小,一侧卵巢上可能黄体遗迹.卵巢萎缩,外观见母牛不发情,直检见卵巢缩小,组织萎缩,质度硬,无卵泡和黄体,子宫也往往缩小.治疗一般采用激素疗法,可采用肌肉注射HCG 1000～3000IU,必要时可间隔1～2天重复注射一次;肌肉注射FSH 100～200IU,每天或隔天一次,共用2～3次,还可配合LH进行治疗;肌肉注射孕马血清1000～2000 IU,1～2次;肌肉注射雌二醇4～40mg,此类药物不易大剂量连续用药,否则易引起卵泡囊肿.     

卵巢静止奶牛血液矿物质及生化指标变化研究

为了给牧场防控奶牛卵巢静止疾病提供科学依据,试验选取产后45～60天卵巢静止的和正常发情的中国荷斯坦奶牛各15头,采用抽血检测的方法分析了卵巢静止奶牛血液中矿物质及生化指标的变化情况。结果表明:与正常发情组奶牛相比,卵巢静止组奶牛日泌乳量显著提高(P0.05),发情次数显著减少(P0.05),卵泡直径极显著减小(P0.01);丙氨酸氨基转移酶(ALT)活性显著提高(P0.05),天门冬氨酸氨基转移酶(AST)活性极显著提高(P0.01);血中矿物质镁(Mg)含量显著降低(P0.05);另外,卵巢静止组奶牛血中雌二醇(E_2)浓度极显著降低(P0.01)。说明产后卵巢静止奶牛血液能量、肝功指标、矿物元素及生殖激素等发生了明显变化。     

浅谈奶牛不孕症治疗

奶牛久配不孕是影响奶牛发展的一大障碍。据调查,在育龄奶牛中久配不孕牛只高达30%左右,经过多年的实践,总结出一些奶牛长期不孕的治疗方法,解决了奶牛生产的一大难题。1病因分析及防治1.1卵巢障碍在久配不孕奶牛中,有一部分是由于卵巢障碍引起的。卵巢障碍引起母牛长期不发情或发情不明显。直检有的卵巢上有囊泡,有的卵泡不发育或发育不良,持久黄体或卵巢有萎缩现象,阴道分泌物量少,子宫颈口封闭。1.1.1卵巢静止奶牛长期不发情,直检卵巢大小正常,质地柔软有弹性,卵泡不发育或很小,阴道分泌物量少。对于此类牛,可轻按摩卵巢,注射孕马血清(P…     

Effects of dietary calcium to available phosphorus ratios on bone metabolism and osteoclast activity of the OPG /RANK/RANKL signalling pathway in piglets

Hydroxyapatite, a mineral form of calcium (Ca) and phosphorus (P) that gives bones their rigidity, is the major and essential component of bones and teeth in the human and animal body. A suitable ratio of Ca and P is vital for bone growth. The aim of this study was to explore the effects of dietary calcium to available phosphorus ratios (Ca/AP) on bone metabolism and osteoclast activity of the osteoprotegerin (OPG)/receptor activator of nuclear factor kappa B ligand (RANKL) signalling pathway in piglets. At days 15 and 29, the piglets were assessed for growth performance, blood indicators, cytokines and the OPG/RANK/RANKL signalling pathway. Our results showed that piglets fed a dietary Ca/AP ratio of 2:1 increases growth performance and regulates blood indicators and cytokines (parathyroid hormone (PTH), calcitonin (CT), vitamin D₃ (VD₃)_, insulin‐like growth factor‐1 (IGF‐1), transforming growth factor‐β (TGF‐β), interleukin‐1 (IL‐1), interleukin‐6 (IL‐6), carboxyterminal propeptide of type I procollagen (PICP), tartrate‐resistant acid phosphatase (TRACP), alkaline phosphatase (ALP) and osteocalcin (OCN) content). We also demonstrated that this ratio affects hormone secretion and further bone metabolism through the OPG/RANK/RANKL signalling pathway of osteoclasts. These results indicate that a suitable dietary Ca/AP ratio is vital for bone growth and reduce the incidence of bone diseases such as osteoporosis, providing a practical basis for the raising of piglets.     

Comparison of pharmacodynamic and pharmacokinetic indices of efficacy for 5 fluoroquinolones toward pathogens of dogs and cats

BACKGROUND: Fluoroquinolones are often used interchangeably in dogs and cats. HYPOTHESIS: Predicted therapeutic efficacy differs among fluoroquinolones. ANIMALS: Bacterial pathogens isolated from dogs and cats. METHODS: Using microtube-dilution procedures, percent resistance and 2 pharmacodynamic/pharmacokinetic indices (maximum concentration/minimum inhibitory concentration [Cmax/MIC] [target 0.10] and area under curve/minimum inhibitory concentration [AUC/MIC] [target 0.125]) were compared prospectively at low and high doses (mg/kg) for ciprofloxacin (5 and 20), difloxacin (5 and 10), enrofloxacin (including enrofloxacin+ciprofloxacin) (5 and 20), marbofloxacin (2.5 and 5), and orbifloxacin (2.5 and 7.5). Indices were calculated for organisms represented by < or = 15 isolates. RESULTS: Percent resistance for all Gram-negative (n = 180; 20+/-3%; 39+/-5% for Escherichia coli) and Gram-positive isolates (n = 66; 18+/-3%) did not differ among drugs or organisms. The pattern of Cmax/MIC was generally enrofloxacin+ciprofloxacin > or = enrofloxacin or ciprofloxacin > or = marbofloxacin > or = orbifloxacin > or = difloxacin; and for AUIC/ MIC, enrofloxacin+ciprofloxacin > or = marbofloxacin > or = ciprofloxacin > or = enrofloxacin > difloxacin > orbifloxacin. Among susceptible Gram-negative isolates studied (n = 117), targeted Cmax/MIC or AUC/MIC were achieved in 88% of E. coli, 53% of Proteus mirabilis, and 35% of Pseudomonas aeruginosa; and for susceptible Gram-positive isolates studied (n = 49), 53% of Streptotoccus spp. and Staphylococcus intermedius and 27% of Staphylococcus spp. At the high dose, the proportion of isolates for which a target was reached was: ciprofloxacin, enrofloxacin+ciprofloaxin, and marbofloxacin (77%), enrofloxacin (73%), orbifloxacin (51%), and difloxacin (40%); and at the low dose, enrofloxacin+ciprofloxacin and enrofloxacin (43%), ciprofloxacin (40%), marbofloxacin (39%), orbifloxacin (29%), and difloxacin (28%). CONCLUSIONS: E. coli resistance to fluoroquinolones approximated 40%. For susceptible isolates, enrofloxacin, marbofloxacin, and ciprofloxacin more consistently reached indices associated with predicted efficacy, but only at the high dose.     

Lactobacillus rhamnosus GG promotes M1 polarization in murine bone marrow‐derived macrophages by activating TLR2/MyD88/MAPK signaling pathway

Lactobacillus rhamnosus GG (LGG) is increasingly applied in functional food products and acts as a probiotic model in nutritious and clinical studies. Increasing evidences have revealed the immune modulation of LGG on macrophages. The aim of this study is to investigate the effect of LGG on macrophage polarization of murine bone marrow‐derived macrophages (BMDMs). BMDMs were treated with 10⁸ colony‐forming units (CFU)/ml LGG for 1.5, 3, and 6 hr. Results showed that LGG obviously upregulated the mRNA expression of M1‐associated cytokines (p < .05), including interleukin‐1 beta (IL‐1β), IL‐6, tumor necrosis factor‐alpha (TNF‐α), and inducible nitric oxide synthase (iNOS), whereas had no effect on the expression of M2‐associated markers (p > .05), including arginase 1 (Arg1), mannose receptor, and chitinase‐like protein 3 (YM1). Furthermore, LGG markedly increased the expression of pro‐inflammatory cytokines (IL‐12p40, cyclooxygenase‐2 [COX‐2], and interferon‐γ [IFN‐γ]) (p < .05) and anti‐inflammatory cytokines (IL‐10, IL‐4, and transforming growth factor‐β [TGF‐β]) (p < .05). In addition, we also found that TLR2/MyD88/MAPK signaling pathway was required for LGG‐induced M1 macrophage polarization and M1‐related cytokines expression. Together, these findings demonstrate that probiotic LGG facilitates M1 polarization of BMDMs, suggesting that LGG may have an immunotherapeutic potential in regulating the host defense against pathogen invasion.     

凹凸棒石复合物对肉仔鸡生产性能、免疫机能和抗氧化机能的影响

本试验旨在研究香芹酚/凹凸棒石(CAR/APT)和香芹酚/氧化锌/凹凸棒石(CAR/ZnO/APT)替代抗生素类促生长剂对肉仔鸡生产性能、免疫机能和抗氧化机能的影响。选取1日龄罗斯308肉鸡192只,随机分成3组,每组8个重复,每重复8只,分别饲喂基础饲粮中添加100mg/kg土霉素钙(OTC)、0.1%CAR/APT和0.1%CAR/ZnO/APT的饲粮,基础饲粮不含抗生素类促生长剂。结果表明:与OTC组相比,CAR/APT和CAR/ZnO/APT对肉鸡1~21日龄生产性能无显著影响(P>0.05)。与OTC组21日龄肉鸡相比,CAR/ZnO/APT对胸腺和脾脏器官指数无显著影响(P>0.05),显著降低法氏囊器官指数(P<0.05);CAR/APT对法氏囊指数无显著影响(P>0.05),显著降低胸腺和脾脏器官指数(P<0.05)。与OTC组21日龄肉鸡相比,CAR/ZnO/APT显著提高血清IgG含量(P<0.05),CAR/APT对血清免疫球蛋白含量无显著性影响(P>0.05)。与OTC组21日龄肉鸡相比,CAR/ZnO/APT有提高空肠黏膜sIgA和IgG含量的趋势(P=0.055);CAR/ZnO/APT组空肠黏膜IgM含量显著高于CAR/APT组(P<0.05)。与OTC组21日龄肉鸡相比,CAR/ZnO/APT显著提高血清和空肠黏膜中T-AOC及血清CAT活性(P<0.05);CAR/APT显著提高血清CAT活性和空肠黏膜T-AOC(P<0.05);CAR/ZnO/APT组21日龄肉鸡血清和空肠黏膜T-AOC显著高于CAR/APT组(P<0.05)。结果表明,以0.1%CAR/APT或CAR/ZnO/APT替代饲粮中的OTC,对肉仔鸡生产性能无显著影响,具有提高免疫机能和抗氧化机能的作用,其中CAR/ZnO/APT效果更优。     

Enhancing mucosal immunity in mice by recombinant adenovirus expressing major epitopes of porcine circovirus-2 capsid protein delivered with cytosine-phosphate-guanosine oligodeoxynucleotides

A recombinant replication-defective adenovirus expressing the major epitopes of porcine circovirus-2 (PCV-2) capsid protein (rAd/Cap/518) was previously constructed and shown to induce mucosal immunity in mice following intranasal delivery. In the present study, immune responses induced by intranasal immunization with a combination of rAd/Cap/518 and cytosine-phosphate-guanosine oligodeoxynucleotides (CpG ODN) were evaluated in mice. The levels of PCV-2-specific IgG in serum and IgA in saliva, lung, and intestinal fluids were significantly higher in the group immunized with rAd/Cap/518 and CpG ODN than animals immunized with rAd/Cap/518 alone. The frequencies of IL-2-secreting CD4⁺ T cells and IFN-γ-producing CD8⁺ T cells were significantly higher in the combined immunization group than mice immunized with rAd/Cap/518 alone. The frequencies of CD3⁺, CD3⁺CD4⁺CD8^-, and CD3⁺CD4^-CD8⁺ T cells in the combined immunization group were similar to that treated with CpG ODN alone, but significantly higher than mice that did not receive CpG ODN. PCV-2 load after challenge in the combined immunization group was significantly lower than that in the phosphate-buffered saline placebo group and approximately 7-fold lower in the group treated with CpG ODN alone. These results indicate that rAd/Cap/518 combined with CpG ODN can enhance systemic and local mucosal immunity in mice, and represent a promising synergetic mucosal vaccine against PCV-2.     

Post mortem evaluation of palmar osteochondral disease (traumatic osteochondrosis) of the metacarpo/metatarsophalangeal joint in Thoroughbred racehorses

Reasons for performing study: Thoroughbred racehorses are commonly affected by subchondral bone injury, but the exact prevalence and the distribution of palmar/plantar osteochondral disease (POD) lesions are unknown. The relationship between pathologies has not been elucidated, although it is widely accepted that POD is a manifestation of traumatic overload arthrosis. Hypothesis: There is an association between grade of POD and other pathologies affecting the third metacarpal and metatarsal (MC/MTIII) condyles (wear lines, cartilage loss, marginal remodelling, dorsal impact injuries and linear fissures). Objectives: To evaluate the pathology found affecting the distal MC/MTIII condyles of Thoroughbred racehorses at post mortem examination, to describe the prevalence and distribution of POD lesions within a population of racing Thoroughbreds and to determine relationships between pathologies of the distal condyles of the third metacarpal and metatarsal bones. Methods: The metacarpo/metatarsophalangeal joints of 64 Thoroughbred racehorses were examined at routine post mortem examination and graded for third metacarpal and metatarsal condylar pathology. Associations between pathologies were determined. Results: POD had a within horse prevalence of 67%. There was a significant linear relationship between grade of POD and grades of wear lines, cartilage ulceration and dorsal impact injuries. There was a significant relationship, but this was not linear, between grade of POD and grade of linear fissures. Using ordinal logistic regression, compared to condyles with grade 0 or grade 2 linear fissures, condyles with grade 1 linear fissures were found to be more likely to have a lower POD grade. Potential relevance: POD can be considered to be a manifestation of traumatic overload arthrosis, but the role of subchondral bone adaptation is complex and warrants further investigation.     

Determination of a dosage regimen of colistin by pharmacokinetic/pharmacodynamic integration and modeling for treatment of G.I.T. disease in pigs

Colistin is an antimicrobial drug of the polymyxin group and COLIVET SOLUTION is an aqueous solution containing colistin sulphate (2 × 10⁶ IU/mL), formulated for oral administration. The target species is the pig, particularly the suckling and post weaning animal. This investigation was undertaken to provide pharmacokinetic and pharmacodynamic data on which to base the selection of dosage rate and interval of the solution for the treatment of porcine colibacillosis.Colistin absorption from the gastrointestinal tract of young pigs, when administered at dosage rates of 25,000, 50,000 and 1,00,000 IU/kg, was slight or absent. The drug was therefore restricted almost entirely to the required site of action. The colistin concentration-time profile within the jejunum and ileum was established, and this enabled determination of the pharmacokinetic variables, maximum concentration (C_max) and area under curve (AUC) and derivation of the surrogate indices of antibacterial activity, C_max/minimum inhibitory concentration (MIC) and AUC/MIC through integration of in vivo data with the results of in vitro potency studies for four strains of Escherichia coli.In the in vitro bacterial growth inhibition studies colistin acted by a concentration-dependent killing mechanism. Numerical values for the surrogate parameter AUC/MIC producing bactericidal and eradication effects of colistin against four strains of E. coli were established by PK-PD modeling based on the sigmoidal E_max equation. These data were used to predict a daily dosage regimen for colistin.     

Characterization and identification of caprine, genital mycoplasmas

A total of 55 mycoplasma strains, isolated from the vagina of goats, were examined. Three strains, being arginine positive and glucose negative, could not be finally classified. Five isolates were identified as Acholeplasma laidlawii. Fourty-seven strains were phosphatase positive, glucose and arginine negative. Nine of these formed “film and spots” on standard growth medium, and reduced tetrazolium aerobically. Serological examination identified 7 as M. agalactiae, while 2 were M. bovis. The remaining 38 isolates did not reduce tetrazolium aerobically, and did not produce “film and spots.” on standard growth medium. All these except one were identified as M. bovigenitalium by immunofluorescence. Their relationship to group 11 otf Al-Aubaidi is discussed.     

喹烯酮在鸡体内的代谢及药物动力学研究

以HPLC-MS/MS为定量手段,研究了喹烯酮经静脉注射(2.5 mg/kg)、口服(30 mg/kg)两种给药途径在鸡体内的代谢及药物动力学特征.鸡静脉注射喹烯酮后,血浆中检测到喹烯酮原药和1-脱氧喹烯酮;口服灌注喹烯酮后,血浆中检测到喹烯酮原药和3-甲基喹噁啉-2-羧酸(MQCA).喹烯酮在鸡体内的药动学数据采用统...     

Effect of porcine glucagon‐like peptides‐2 on tight junction in GLP‐2R + IPEC‐J2 cell through the PI3k/Akt/mTOR/p70S6K signalling pathway

Because of rare glucagon‐like peptide‐2 (GLP‐2) receptor (+) cells within the gut mucosa, the molecular mechanisms transducing the diverse actions of GLP‐2 remain largely obscure. This research identified the naturally occurring intestinal cell lines that endogenously express GLP‐2R and determined the molecular mechanisms of the protective effects of GLP‐2‐mediated tight junctions (TJ) in GLP‐2R (+) cell line. (i) Immunohistochemistry results showed that GLP‐2R is localised to the epithelia, laminae propriae and muscle layers of the small and large bowels of newborn piglets. (ii) GLP‐2R expression was apparent in the cytoplasm of endocrine cells in IPEC‐J2 cell lines. (iii) The protein expressions of ZO‐1, claudin‐1, occludin, p‐PI₃K, p‐Akt, p‐mTOR and p‐p70^S6K significantly (p < 0.05) increased in GLP‐2‐treated IPEC‐J2 cells, and all of them significantly (p < 0.05) decreased when LY‐294002 or rapamycin was added. GLP‐2 improves intestinal TJ expression of GLP‐2R (+) cells through the PI₃k/Akt/mTOR/p70^S6K signalling pathway.