蛋黄中抗嗜水气单胞菌IgY的提取和纯化

通过对蛋黄中抗嗜水气单胞菌IgY的提取,分别进行了两种粗提方法(水稀释法、Pectin法)和纯化方法(硫酸铵法、PEG6000法)的比较。结果显示,当蛋黄液经pH5.0蒸馏水10倍稀释粗提后,上清液中脂肪和IgY残余率分别为32.69%和68.34%,效果较好。采用12%(w/v)PEG6000、33%(v/v)饱和硫酸铵纯化IgY,其免疫活性残余率分别为63.5%和64.1%。SDS-PAGE显示,水稀释法和Pectin法提取的上清液中杂蛋白减少,硫酸铵和PEG6000纯化后的上清液中几乎无其他杂带。研究表明,水稀释法和Pectin法提取IgY具有简便、高效和无污染的特点,硫酸铵和PEG6000适合纯化IgY。     

甲鱼嗜水气单胞菌的分离鉴定及体外抑菌试验

本试验采用分离培养法观察菌落形态特征,微量生化法检测生化特性,PCR扩增法进行分子鉴定,纸片扩散法检测耐药性,牛津杯法检测体外抑菌作用,人工感染动物法检测致病性,以期找到防控甲鱼大量发病的有效办法,对具有典型病状的甲鱼进行细菌分离鉴定。试验结果表明:得到4株形态一致的G-短杆菌JAY-1、JAY-2、JAY-3、JAY-4;均分解葡萄糖、蔗糖、麦芽糖等,不分解乳糖、鼠李糖、木糖等,硝酸盐、枸橼酸盐等为阳性,H2S、尿素等为阴性;均在约1 500 bp处出现目的条带,与气单胞菌同源性最高,与嗜水气单胞菌同一分支;对青霉素G、阿莫西林、林可霉素、头孢氨卞等完全耐药,对红霉素、四环素等耐药,对头孢曲松、环丙沙星、恩诺沙星敏感;8株乳酸杆菌对分离菌均有明显的抑菌圈;攻毒小白鼠24 h内均死亡,均分离到与自然发病株一致的菌株。说明分离菌均为嗜水气单胞菌,乳酸杆菌对分离菌具有显著的抑致作用,头孢曲松、环丙沙星、恩诺沙星等与乳酸杆菌配合用药,可作为临床防控嗜水气单胞菌的参考依据。     

黄鳝嗜水气单胞菌的分离鉴定及中药体外抑菌效果研究

黄鳝出血病又叫败血症。该病主要由嗜水气单胞菌感染所致,其发病率与死亡率高,给黄鳝养殖业带来了巨大的损失。本试验在出现黄鳝败血症的养殖场病鳝体中分离到了嗜水气单胞菌,并选取大黄、黄芩、黄柏、黄连、五倍子、穿心莲、虎杖、金银花、杜仲、石榴皮、钩藤、板蓝根12种单味中药,采用纸片法对其做体外抑菌试验,从而评价中草药对该菌的抑菌效果,为以后开发中药制剂和黄鳝出血症的预防奠定理论基础。     

50种中草药体外抑杀嗜水气单胞菌的药效研究

为筛选有效抑制嗜水气单胞菌(A.hydrophila)的中草药,以期为水产养殖业中防治该菌引起的疾病提供实验依据.本研究采用琼脂扩散法(打孔法)测定了地榆等50种中草药对A.hydrophila的抑制作用,并用二倍稀释法测定抑菌效果较强的25种中草药对A.hydrophila的最小抑菌浓度(MIC)和最小杀菌浓度(MBC).结果显示地榆的抑菌效果最好,其抑菌圈直径达20mm以上,MIC为3.91 mg/mL,MBC为7.81 mg/mL;黄连等24种中草药有一定的抑菌和杀菌效果,巴戟天等25种中草药无抑菌作用.结果表明地榆对A.hydrophila的体外抑制效果最好.     

佐剂对嗜水气单胞菌灭活疫苗免疫效果的作用

制备嗜水气单胞菌J—1株福尔马林灭活疫苗，用浸浴法免疫银鲫。设疫苗加IMS1312佐剂免疫组、不加佐剂疫苗免疫组及未免疫对照组，每组20尾。18～20℃水温饲养35d，检测银鲫血清嗜水气单胞菌凝集抗体。佐剂组抗体效价达1：64，相对保护率为67％。不加佐剂免疫组抗体效价为1：32，相对保护率达56％。对照组抗体效价为1：4，相对保护率为10％。试验结果表明浸浴免疫对银鲫具有较好的保护力，佐剂IMS1312可增强鱼体的免疫应答。     

5种中药提取物及其组合对嗜水气单胞菌的体外抑制作用

试验旨在探讨大黄、诃子、五倍子、黄连、黄芩5种中药及其组合对嗜水气单胞菌的体外抑制作用。试验测定了5种中药的水提物和醇提物对3株嗜水气单胞菌的抑菌圈、最低抑菌浓度（MIC）、最低杀菌浓度（MBC）及对嗜水气单胞菌生长的影响,采用棋盘交叉法测定了5种中药联合抑菌作用。结果显示,大黄和黄芩醇提物的抑菌圈显著高于其水提物（P<0.05）,诃子和黄连水提物的抑菌圈显著高于其醇提物（P<0.05）,五倍子水提物和醇提物抑菌圈大小相近。五倍子抗菌作用最强,其水提物和醇提物MIC为7.81～15.63 g/L,大黄醇提物和诃子水提物抗菌作用次之,MIC均为15.63～31.25 g/L。选择抑菌作用更强的提取物两两组合,五倍子水提物与其他4种中药提取物组合、大黄醇提物与黄连水提物组合均为协同作用;黄连水提物与黄芩醇提物组合为相加作用;大黄醇提物与黄芩醇提物、诃子水提物与黄连水提物组合均为无关作用;诃子水提物与黄芩醇提物组合为拮抗作用。研究表明,5种中药对嗜水气单胞菌均具有抑制作用,五倍子作用最强,五倍子水提物与其他4种中药提取物两两组合、黄连水提物与黄芩醇提物组合均可增强抗菌活性。     

植物精油对嗜水气单胞菌和无乳链球菌的抑菌效果

本研究旨在通过在细菌培养基中添加不同浓度的植物精油产品智然香和抗敌素,接种嗜水气单胞菌和无乳链球菌,探求植物精油产品智然香和抗敌素对两种水生致病菌的最低抑菌浓度。试验方法:采用琼脂平板法,在培养基中添加不同浓度的植物精油产品智然香和抗敌素,分别接种嗜水气单胞菌和无乳链球菌,测定植物精油产品智然香和抗敌素对细菌的抑制效果和最低抑菌浓度。结果表明:植物精油产品智然香和抗敌素对嗜水气单胞菌的最低抑菌浓度分别为2%和0.7%,对无乳链球菌的最低抑菌浓度分别为4.6%和1%。植物精油产品智然香可以以较小浓度抑制嗜水气单胞菌的生长,可用于嗜水气单胞菌感染引起的水生动物疾病预防和控制。     

鸭嗜水气单胞菌病的病原鉴定和免疫试验

１流行病学和症状某地区几处养鸭场自１９９０年初发生鸭陆续死亡,曾用鸭肝炎卵黄抗体治疗无效,曾用死鸭脏器制成灭活组织苗使用,收到一定效果。１９９７年９月～１０月,天气仍炎热、渔湖区秋江鸭场又发生２０～４０日龄鸭急性死亡,其主要症状：开始食欲减少,呼吸困...     

中药单味药及复方对嗜水气单胞菌的体外抑菌作用

本试验用煎煮法提取中药有效成分,采用琼脂平板扩散法探讨了黄连、五倍子、大黄、诃子等中药单味药及中药复方对嗜水气单胞菌(Aeromonas hydrophila)的体外抑菌作用,测定了抑菌圈大小.采用双倍试管稀释法测得了最小抑菌浓度(MIC)和最小杀菌浓度(MBC).试验结果表明,16种中药提取物对嗜水气单胞菌有不同程度的抑制作用,其中五倍子、黄连、诃子、大黄的水提物的抑菌效果最好,MIC值分别为7.81 mg/mL、15,63 mg/mL、31.25 mg/mL、62.50 mg/mL.五倍子作为主药,分别与诃子、黄连、大黄接一定比例组成的复方的MIC分别为3.906 mg/mL、7.813 mg/mL、15.625 mg/mL.通过对筛选的复方与市场上销售的3种成品复方的体外抑菌活性的比较,发现本实验室筛选的复方对嗜水气单胞菌的体外抑菌活性更强.     

多种维生素“嘉利补”对蛋种鸡生产性能和抗体水平的影响

本试验旨在研究嘉利补对蛋种鸡生产性能的影响。选取160日龄海兰灰父母代蛋种鸡1200只,随机分为2个处理,每个处理3个重复。采用单因素随机试验设计。试验组在基础日粮中添加2g/kg嘉利补,对照组饲喂基础日粮,试验期24d。结果表明:添加嘉利补组蛋种鸡产蛋率和蛋黄相对重较对照组分别提高4.83%(P0.05)和8.97%(P0.05);料蛋比、破蛋率和淘汰率分别降低6.40%(P0.05)、22.50%(P0.05)和21.28%(P0.05);免疫后14d和28d,抗体滴度分别提高2.86%(P0.05)和10.70%(P0.05);受精率和受精蛋孵化率均高于对照组;试验末平均每只蛋种鸡每天多获利0.13元。     

Studies on effects of nutritional factors on bone structure and osteoporosis in laying hens

1. A modern hybrid strain of laying hen (Hisex) was fed from point of lay to 68 weeks on a control diet and diets containing oystershell, fluoride, 1,25‐dihydroxycholecalciferol, ascorbic acid, a lower concentration of phosphorus and a combination of a lower concentration of crude protein and higher concentration of vitamin K. Hens from a much older strain (Brown Leghorn J‐line) were fed on the control diet.

2. Plasma variables were measured during lay. End‐of‐lay trabecular and medullary bone volumes in the proximal tarsometatarsus and free thoracic vertebra were measured by histomorphometry.

3. The majority of Hisex hens were considered to be osteoporotic by the end of lay. In contrast, none of the J‐line were osteoporotic.

4. None of the nutritional treatments affected trabecular bone volumes. Medullary bone volumes were increased significantly by feeding oystershell or fluoride.

5. There was no phenotypic correlation between egg production and trabecular bone volume in the Hisex hens.

6. The experiment provided evidence that osteoporosis in laying hens, as assessed by trabecular bone volumes, is not caused by calcium deficiency and could not be prevented by any of the nutritional treatments studied.     

日粮中长期添加大豆黄酮对产蛋鸡产蛋性能及有关内分泌的影响

试验旨在探讨日粮中长期添加大豆黄酮对产蛋高峰期蛋鸡采食和生产性能的影响及有关内分泌机制。40羽180日龄产蛋鸡,均分为2组,对照组饲喂基础日粮,试验组饲喂基础日粮+大豆黄酮(6mg/kg),试验期为150d。结果显示:试验组蛋鸡采食量、产蛋率、只日蛋重、每枚蛋重均显著提高,料蛋比显著下降;血清17β-雌二醇、T3、T4水平均显著提高,而血清瘦素(leptin)水平有下降的趋势。试验结果表明,大豆黄酮可调控血液激素水平而提高产蛋鸡生产性能,并使产蛋高峰期得到延长。     

蛋鸡磷营养状况检测的敏感性指标探讨

本试验在0.1%、0.2%、0.4%3个水平有效磷条件下，测定检测蛋鸡磷营养充足与否的常用指标，结果表明：6周内，0.1%有机磷对生产性能、胫骨总灰重、灰分含量、钙含量及血磷、血钙、血中碱性磷酸酶活性无显著影响（P＞0.05），对骨磷含量有显著（P＜0.05）降低作用。检测机体磷缺乏的常用指标中，骨磷含量最敏感。     

禽流感灭活疫苗甲醛含量测定及对产蛋鸡雌二醇的影响

自2003年以来我国使用禽流感灭活疫苗后很好地控制了禽流感的发生和流行,但养鸡的主要省份相继出现了免疫后产蛋鸡高峰生产性能下降.为探讨其发病的内在机制,收集发病地区使用的不同品种、不同厂家禽流感灭活疫苗,测定其中的甲醛含量;收集甲醛含量不同的禽流感疫苗免疫血清,利用放免法测定血清中E2(雌二醇)激素水平,并测定产蛋率.结果表明,发病鸡群使用过的禽流感灭活疫苗内甲醛含量分别为:0.34%(Re-1株)、0.59%(Re-4株)、0.77%(Re-1 Re-4二价苗)、0.33%(H5 H9二价苗),经甲醛含量不同的禽流感疫苗免疫和未免疫鸡只产蛋率分别为70.0%、91.0%和92.5%,血清中E2水平分别为33.71 pg/mL、57.55 pg/mL和82.70 pg/mL,且差异极显著.因此,禽流感灭活疫苗内甲醛含量过高造成雌激素分泌下降可能是造成产蛋性能下降的主要因素之一.     

海藻饲料添加剂对蛋鸡产蛋性能、血清抗氧化性及生长的影响

试验研究了在蛋鸡饲粮中添加不同剂量的海藻饲料添加剂对蛋鸡产蛋性能、血清抗氧化性、生长及营养物质消化率等的影响。选取360只26周龄体重相近的海兰褐蛋鸡,随机分为6组(每组3个重复,每个重复20只鸡),1组为空白对照组,饲喂基础饲粮;2组为抗生素对照组,在基础饲粮中添加0.005%的杆菌肽锌;3~6组为试验组,分别在基础饲粮中添加0.02%、0.04%、0.06%、0.08%的菊粉,0.025%、0.050%、0.100%、0.150%的大西洋海藻粉及相同剂量的铜藻粉(以下简称低、中、较高、高剂量海藻复合物),预试期7 d,正式试验期63 d。结果表明:海藻饲料添加剂对蛋鸡的产蛋性能有明显的剂量-效应关系,添加量为中等剂量海藻复合物(4组)时最佳且差异显著(P<0.05)。此添加量下,蛋鸡血清中超氧化物歧化酶活性最高(P<0.05)。试验中粗纤维的表观消化率随添加剂量的增加而增加(P<0.05)。低剂量试验组体重增长最多且差异显著(P<0.05)。试验结果表明,基础饲粮中添加中剂量海藻复合物作为蛋鸡饲料添加剂,能够显著提升蛋鸡产蛋性能及血清抗氧化性。     

白藜芦醇对产蛋后期蛋鸡肝脏抗氧化酶活性和mRNA表达的影响

试验旨在研究饲粮中添加白藜芦醇(Res)对产蛋后期蛋鸡肝脏抗氧化能力和相关基因表达的影响。360只60周龄健康京粉1号蛋鸡,随机分为5组,每组6个重复,每个重复含有12只鸡。对照组饲喂基础日粮,试验组饲喂在基础日粮水平上添加0.05%、0.10%、0.20%、0.40%白芦藜醇的试验饲粮。预试期为1周,试验期为8周。结果表明:随着白藜芦醇水平的升高,肝脏中总抗氧化能力、总超氧化物歧化酶和谷胱甘肽过氧化物酶的活性均会上升,肝脏Mn-SOD和Cu/Zn-SOD的mRNA表达量也会增加。由此可见,白藜芦醇提高抗氧化酶活力和上调抗氧化酶基因表达,可能是通过调节抗氧化酶基因的表达从而发挥抗氧化作用。     

Detection of chicken anemia virus in the gonads and in the progeny of broiler breeder hens with high neutralizing antibody titers

Previous evidence for the presence of chicken anemia virus (CAV) in the gonads of immune specific-pathogen-free chickens raised the question whether this occurs also in commercial breeders. The presence of CAV was investigated by nested PCR in the gonads and spleens of hens from two 55- and 59-week-old, CAV-vaccinated (flocks 2 and 3), and two 48- and 31-week-old non-vaccinated broiler breeder flocks (flocks 1 and 4). In addition, lymphoid tissues of 20-day-old embryos from these hens were also investigated for the presence of CAV. CAV was detected in the gonads and of 5/6 and 11/22 of the vaccinated hens and in some hens also in the spleen alone. Embryos from 7/8 and 5/18 of these hens were positive. In the non-vaccinated flocks, CAV was detected in the gonads of 11/34 and 10/10 hens in flocks 1 and 4, respectively. In addition, 11 birds in flock 1 had positive spleens. CAV DNA was detected in 3/11 and 2/10 of their embryos. CAV-positive gonads and embryos were detected in samples from hens with moderate as well as high VN antibody titers. Vaccinated chickens positive for CAV in the gonads and in their embryos had VN titers ranging from >1:512 to <1:2048. In non-vaccinated chickens, the VN titers of CAV positive chickens ranged from 1:128 to 1:4096. These results demonstrate that CAV genome can remain present in the gonads of hens in commercial broiler breeder flocks even in the presence of high neutralizing antibody titers that have been associated with protection against CAV vertical transmission. It also suggests that transmission to the progeny may occur irrespectively of the level of the humoral immune response in the hens.     

酵母硒对蛋鸡血清酶活性及抗氧化能力的影响

为研究酵母硒对蛋鸡血清酶活性及抗氧化能力的影响,试验选用1 000只280日龄的海兰褐壳蛋鸡,随机分为5组,每组5个重复,每个重复40只,分别为基础饲粮组,以及0.1,0.2,0.3和0.4mg/kg酵母硒添加水平组,试验期40d。结果表明:与对照组相比,各试验组均可显著提高血清ALP和LDH活性(P<0.05),并显著降低CK活性(P<0.05);与对照组相比,饲粮添加0.2,0.4mg/kg酵母硒均可显著提高血清SOD活性(P<0.05),其他试验组SOD活性与对照组无显著性差异(P>0.05);各试验组GSH-Px和T-AOC水平均显著高于对照组(P<0.05),而血清MDA含量均显著低于对照组(P<0.05)。试验结果提示,酵母硒可提高蛋鸡抗氧化能力,且以添加0.3,0.4mg/kg为宜。     

Comparison of antibody titers in rabbits following immunization with inactivated influenza virus via subarachnoidal or subcutaneous route

Rabbits were immunized with inactivated influenza virus via the subarachnoidal (SA) or subcutaneous (SC) route, and the antibody titers in cerebrospinal fluid (CSF) and serum were assayed. There were no nervous signs or morphological lesions related to SA immunization. In the SC group, the antibody titer was elevated in serum, but not elevated in CSF. In the SA group, the antibody titer was significantly elevated in serum and even in CSF, and their antibody titers were much greater than in the SC group. The present results suggest that intrathecal immunization is more effective than SC immunization at inducing a protective immune response against the transneural spread of viruses.