鸭疫里默氏杆菌感染后雏鸭血清生化指标变化的研究

利用生化自动分析仪对人工感染Ⅰ型鸭疫里默氏杆菌(含菌量3*109CFU)的20日龄天府肉鸭血清GLU、TC、LDH、ALT、AKP、AMS进行了测定。结果表明:GLU、TC、LDH、ALT在发病高峰期均显著升高(P≤0.01),AKP、AMS有升高,但与对照组相比无差异。     

鸭疫里默氏杆菌病研究进展

1病原 鸭疫里默氏杆菌为革兰氏阴性小杆菌,不形成芽胞,不运动,纯培养物涂片可见菌体呈杆状,有的呈椭圆形,单个、成对或呈短链状排列,大小不等,(03～05)um×(1～5)um,瑞氏染色有两极染色特征,用印度墨汁染色可见到荚膜.本菌为严格需氧菌,对营养要求较高,在普通琼脂和麦康凯琼脂培养基上不生长,在胰酶大豆琼脂、巧克力琼脂、血液琼脂培养基上生长良好.     

免疫组化检测鸭疫里默氏杆菌(RA)方法的建立

本文建立了间接免疫组化法(HRP-间接法)检测组织中的鸭疫里默氏杆菌,并从固定液、抗原修饰方法、洗涤液和洗涤方法、复染液、粘片剂几个方面进行了优化,其结果为以PLP为固定液,以APES为粘片剂,以0.3%的甲醇-H2O2在湿盒中室温下孵育20min消除组织中的过氧化物酶及假过氧化物酶活性,兔抗RAIgG与羊抗兔-HRP的稀释比例均为1∶25,以4℃过夜作兔抗RAIgG的孵育条件,以10%白蛋白0.05%Tween-20pH7.4的PBS湿盒内室温孵育60min处理组织中非特异性染色因素;以TBST为洗涤液,空气振荡器70转/min摇洗2次,每次10min洗涤切片;以0.5%甲苯胺蓝作为复染液。此方法具有特异性强,无假阳性,经济,无需特殊仪器,简单易行的优点。     

免疫组化检测鸭疫里默氏杆菌（RA）方法的建立

本文建立了间接免疫组化法（HRP-间接法）检测组织中的鸭疫里默氏杆菌，并从固定液、抗原修饰方法、洗涤液和洗涤方法、复染液、粘片剂几个方面进行了优化，其结果为以PLP为固定液，以ALES为粘片剂，以0.3％的甲醇-H2O2在湿盒中室温下孵育20min消除组织中的过氧化物酶及假过氧化物酶活性，免抗RAlgG与羊抗兔-HRP的稀释比例均为1：25，以4℃过夜作兔抗RAlgG的孵育条件，以10％白蛋白0．05％Tween-20pH7．4的PBS湿盒内室温孵育60min处理组织中非特异性染色因素；以TBST为洗涤液，空气振荡器70转／min摇洗2次，每次10min洗涤切片；以0．5％甲苯胺蓝作为复染液。此方法具有特异性强，无假阳性．经济，无需特殊仪器，简单易行的优点。     

鸭疫里默氏杆菌病的诊断及防制探讨

鸭疫里默氏杆菌病（RiemerellaanatifdrRA）又称鸭疫巴氏杆菌病，鸭传染性浆膜炎等，是由鸭疫里默氏杆菌引起的鸭的一种接触性、急性或慢性，败血性的传染病，是当前造成养鸭业经济损失的最主要传染病之一，广泛分布于世界上各养鸭国家。我国自１９８２年郭玉璞在北京首次报道该病后，我国各地相继报道了该病的发生。２００２年５月份湖南省衡阳县某养鸭专业户饲养的肉鸭，相继发生一种传染病，经流行病学调查、临床观察、病理剖检、病原分离鉴定、动物试验确诊为鸭疫里默氏杆菌病，经药敏试验选取敏感药物丁胺卡那霉素、环丙沙星等进行治…     

我国对鸭疫里默氏杆菌病的研究

鸭疫里默氏杆菌(Riemerella anatipestifer,RA)病,又称鸭疫巴氏杆菌病、鸭败血症、鸭疫综合症、鸭传染性浆膜炎,是鸭、鹅、火鸡和各种其它鸟类的一种接触性传染疾病,主要以神经症状和纤维素性心包炎,肝周炎和气囊炎为特征.是养鸭业最为严重的传染病之一.     

雏鸭混合感染鸭疫里默氏杆菌和大肠杆菌的诊断和防治

不少鸭场和农户散养的鸭群,常在2～3周龄发病,死亡率较高.我们从养殖户送检的病鸭和死鸭的肝脏、心血、脑等部位分离出了两种可疑细菌.经病理剖检、接种专用培养基、染色镜检、生化鉴定,确诊为鸭疫里默氏杆菌和大肠杆菌的混合感染.经动物试验证实了分离菌的致病性,并对分离菌进行药物敏感性试验,现将结果报道如下.     

鸭疫里默氏杆菌病的诊治

<正>鸭疫里默氏杆菌病又称鸭传染性浆膜炎,是由鸭疫里默氏杆菌引起的侵害雏鸭的慢性或急性败血性传染病,该病一年四季均有发生,是危害养鸭业最为严重的传     

鸭疫里默氏杆菌病的流行情况与防制措施

<正>鸭疫里默氏杆菌病(又称鸭传染性浆膜炎)是由鸭疫里默氏杆菌感染引起的以危害幼龄鸭为主的一种急性、接触性、细菌性传染病,本病主要症状为下痢、瘫痪、咳嗽、运动障碍,解剖病变以纤维素性肝周炎、心包炎、气囊炎为主。     

鸭疫里默氏菌的分离和鉴定

为明确规模化鸭场病因,开展了鸭疫里默氏菌的分离和鉴定。通过采集病料进行实验室诊断,经细菌分离鉴定及PCR特异性扩增、产物测序鉴定方法,明确从规模化鸭场分离得到的细菌为鸭疫里默氏菌。检测结果为鸭场制定科学的预防和治疗方案提供了参考,对及时治疗病鸭、防止疾病传播、减少养鸭场的经济损失具有重要意义。     

Direct Detection of Target Genes in Viable Bacteria and Extracellular DNA Using Loop-Mediated Isothermal Amplification Assay

When the loop-mediated isothermal amplification (LAMP) assay is used for detecting target genes, DNA extraction is unnecessary in many cases. Simple pretreatment (e.g. heating) is enough to obtain rather sensitive responses. Even test samples without any pretreatment can be used as template. This feature suggests that LAMP is superior to PCR in developing point-of-care test strategies. In this study, using Stx1 gene from E. coli as model, we verified that viable cells, dead cells and extracellular DNA could function as template in the LAMP assay. In the incubation at 63℃, viable bacteria in the LAMP reaction mixture lysed completely within 2 min, providing DNA template for nucleic acid amplification. The Stx1 gene in diluted culture medium, spiked tap water, spiked seawater and real seawater all could be detected, with or without the step of DNA extraction. We found that the complex substances in real sample (e.g. natural seawater) exhibited considerable inhibitory effect on the sensitivity of the LAMP assay. These outcomes are meaningful for building a point-of-care strategy by employing the LAMP assay for environmental monitoring, bio-resource surveys, food safety, etc. in particular those based on environmental DNA.     

Optimal Immobilization of Acidic Proteases from Monterey Sardine (Sardinops sagax caeurelea) on Partially Deacetylated Chitin from Shrimp Head Waste

ABSTRACT

Response surface methodology was employed to optimize the immobilization yield of acidic proteases from Monterey sardine (Sardinops sagax caeurelea) using partially deacetylated chitin as immobilization support. A rotatable central composite design was applied to evaluate the effects of immobilization conditions such as enzyme loading (X₁), immobilization pH (X₂), and tripolyphosphate concentration (X₃) on the immobilization yield. The analysis of variance revealed that the established model was significant (p < 0.05), and the adjustment of the quadratic model with the experimental data was satisfactory. Under optimal conditions (X₁ = 0.05 mg/mL, X₂ = 3.16, and X₃ = 0.75%), an immobilization yield of 79.1% was achieved; a value that was in accordance with the predicted one.     

鱿鱼鱼精蛋白的提取_纯化及其生化特性

鱼精蛋白（Ｐｒｏｔａｍｉｎｅ）是一种常与ＤＮＡ结合,存在于鱼类成熟精巢中的碱性蛋白。由于其生化组成的特点,鱼精蛋白不仅具有促使细胞发育繁殖的作用,而且一旦将其分离出来,能有效抑制多种食品腐败菌的生长和繁殖［Ｍｉｌｅｒ１９４２］。同时,这种鱼精蛋白还有...     

哈维氏弧菌(Vibrio harveyi)ML01株胞外产物及分泌性蛋白的分离与特性分析

本研究以引起珍珠龙胆石斑鱼[Epinephelus fuscoguttatus(♀)×Epinephelus lanceolatus(♂)]幼鱼“皮肤溃疡病”的哈维氏弧菌(Vibrio harveyi) ML01株为研究对象,采用平板膜覆盖技术和柱层析技术,分离、纯化了ML01株的胞外产物及分泌性蛋白.应用毒性试验、质谱分析与分子克隆技术,对纯化的胞外产物和3种主要的分泌性蛋白进行了特性分析与鉴定.结果显示,哈维氏弧菌ML01株的胞外产物(Extracellular products,ECPs)具有酯酶、明胶酶、淀粉酶、酪蛋白酶活性,无脲酶活性.ECPs对羊红细胞无溶血性,对斑马鱼(Danio rerio)的半数致死剂量(LD50)为19.55μg/g鱼体重.从ML01株中分离到3种主要的分泌蛋白P42、P36、P31,其分子量分别为42、36、31 kDa.经质谱鉴定和分析,这3种蛋白分别为哈维氏弧菌的外膜蛋白OmpU和OmpN,以及一种功能未知的蛋白.利用同源克隆,成功地从ML01株基因组中扩增到了P42、P36、P31的基因.序列测定和比对结果显示,ML01株的这3个基因与哈维氏弧菌ATCC 33843(GenBank CP009467)的相应基因相比,其开放阅读框(Open reading frame,ORF)序列的相似性分别为97.08％、100％、99.67％,其编码的多肽序列的相似性分别为99.71％、100％和99.93％.本研究对进一步分析哈维氏弧菌ML01株的致病机理、研发该菌的亚单位疫苗具有重要的参考价值.     

Digestive enzyme activity during larval development of the Senegal sole (Solea senegalensis)

The activities of the main digestive enzymes (proteases, amylase, lipase) as well as those of acid and alkaline phosphatases were assessed during the larval development of the Senegal sole, Solea senegalensis. Important variations in specific activities of all the enzymes were observed during the period of study and were mostly related to the beginning or the end of metamorphosis. Both acid and alkaline protease activities were identified at early stages of development. Acid proteases accounted for only 10% of total protease activity in a 9 days-old larva, but exceeded 75% in a 33 days-old individual. Maximum lipase activity was related to the development of exocrine pancreas (days 6 to 10) and to metamorphosis. It is suggested this can be related to the metabolism of lipid reserves taking place during this morphological change. Activity of alkaline phosphatase decreased from day 5 to day 20 but therafter revealed a sharp increase, possibly linked to the development of enterocytes. The pattern of development of the main digestive enzymes found in S. senegalensis is similar to that described in other flatfish species.     

Comparative Studies of the Proteolytic Activity of Crude Extracts from the Digestive Tract of Three Shark Species

Abstract

The level of pepsin, trypsin, chymotrypsin and leucine aminopeptidase (LAP) was measured in the digestive organs of Portuguese dogfish, leafscale gulper shark, and lowfin gulper shark. The highest pepsin activity was measured in the cardiac stomach. Trypsin was not detected in leafscale gulper shark, and chymotrypsin was mainly measured in the intestine. LAP was detected in all organs and species. The temperature optima of pepsin, trypsin and chymotrypsin were between 42 and 48°C and those of LAP in the 50-56°C range. Pepsin from Portuguese dogfish was considerably activated during pre-incubation. Trypsin, chymotrypsin and LAP from lowfin gulper shark were reasonably activated when pre-incubated but that was not evident in these proteases from Portuguese dogfish and leafscale gulper shark.     

Digestive Proteases of Pacu,Piaractus mesopotamicus,Fed on Distinct Protein-Starch Diets

Abstract

Fish adjust the enzyme profile to dietary protein and carbohydrate. A balance of nutrients optimizes the enzyme profile and metabolic performance offish. Dietary levels (10, 20, 30 and 40%) were combined to four levels of starch (57, 32, 21 and 4%) to feed juvenile pacu, Piaractus mesopotamicus. Acid and alkaline proteases were color-imetrically determined by hemoglobin and azocasein hydrolysis, respectively. Liver, white and red muscle glycogen, glucose and free amino acids were colorimetrically quantified. Those enzyme activities were induced by dietary protein. Enzyme responses to the feeding and the metabolic profile of the tissues suggest the best protein/starch ratio as 30%/21%. The highest levels of protein (30%-40%) impaired nutrient uptake.     

饥饿后再投喂对星斑川鲽生化组成以及能值的影响

采用饥饿不同时间后再恢复投喂相同时间的方法,在温度19±1℃、盐度32±1的条件下,对相同规格的星斑川鲽(26.02±0.30 g)鱼体和粪便的生化组成以及能值等相关指标的影响进行了研究.研究结果表明,饥饿后再投喂对星斑川鲽鱼体内水分、脂肪和灰分的含量影响显著,对鱼体内蛋白质含量无显著影响;对粪便脂肪和蛋白质含量影响显著,对粪便中灰分无显著影响;对鱼体能值影响显著,对粪便的能值无显著影响.研究还发现,饥饿处理时间越长,各相关指标变化越显著;随着恢复投喂的进行各相关指标逐渐恢复到对照组水平,饥饿处理时间越长,恢复到对照组水平所需要的时间越长.     

梅童鱼内源蛋白酶自水解工艺的优化

为提高海捕低值鱼加工利用率,合理利用鱼糜及鱼糜制品加工中的副产物,充分利用鱼类自身内源酶,寻求低值鱼精深加工的低碳高效利用,以梅童鱼(Collichthys lucidus)为研究对象,利用鱼类自身的内源蛋白酶将鱼体内的蛋白质酶解,在自然p H条件下,观察了液料比、自溶温度、时间对梅童鱼蛋白水解的影响,以可溶性蛋白/总蛋白的值为响应值,采用响应面分析优化自溶条件。通过求解回归方程得到的最优自溶条件为:液料比3.4,温度53℃,时间267 min。经过验证,可溶性蛋白/总蛋白的值为18.35%,与回归方程的预测值18.55%相比,相对误差1.1%,说明模型能较好地预测自溶过程中可溶性蛋白/总蛋白的值。在此条件下,测得水解度为15.84%,过0.45μm微滤膜蛋白质量比为9.83%。研究表明,该水解工艺可为生产鱼露、活性肽、氨基酸等提供技术依据。