Protective efficacy of an H5/H7 trivalent inactivated vaccine produced from Re-11, Re-12, and H7-Re2 strains against challenge with different H5 and H7 viruses in chickens

We developed an H5/H7 trivalent inactivated vaccine by using Re-11, Re-12, and H7-Re2 vaccine seed viruses, which were generated by reverse genetics and derived their HA genes from A/duck/Guizhou/S4184/2017(H5 N6)(DK/GZ/S4184/17)(a clade 2.3.4.4 d virus), A/chicken/Liaoning/SD007/2017(H5 N1)(CK/LN/SD007/17)(a clade 2.3.2.1 d virus), and A/chicken/Guangxi/SD098/2017(H7 N9)(CK/GX/SD098/17), respectively. The protective efficacy of this novel vaccine and that of the recently used H5/H7 bivalent inactivated vaccine against different H5 and H7 N9 viruses was evaluated in chickens. We found that the H5/H7 bivalent vaccine provided solid protection against the H7 N9 virus CK/GX/SD098/17, but only 50–60% protection against different H5 viruses. In contrast, the novel H5/H7 trivalent vaccine provided complete protection against the H5 and H7 viruses tested. Our study underscores the importance of timely updating of vaccines for avian influenza control.     

中药对肉仔鸡脂质代谢及肉品质的影响

将120只1周龄肉仔鸡随机分成4组,每组30只,前3组(试验Ⅰ、Ⅱ、Ⅲ组)分别喂以含1%的3种不同中药组方的饲粮,第Ⅳ组为对照组,只喂基础日粮.试验期6周.结果(1)与对照组相比,Ⅰ组血清TC、LDL-C极显著下降(P＜0.01);Ⅱ组血清TC、LDL-C极显著下降(P＜0.01),TG也下降(P＜0.05),HDL-C显著升高(P＜0.01);Ⅲ组血清LDL-C极显著下降(P＜0.01),HDL-C则显著升高(P＜0.01);试验Ⅰ～Ⅲ组血清总脂都极显著下降(P＜0.01);与Ⅱ组相比,Ⅰ组血清LDL-C、Ⅲ组TC存在显著差异(P＜0.01).(2)与对照组相比,胸肌组织中,各试验组TG极显著下降(P＜0.01),Ⅱ组TC显著下降(P＜0.05);腿肌中,各组TC显著下降(P＜0.05),TG下降极显著(P＜0.01);肝脏中各组TC、TG均极显著下降(P＜0.01);与Ⅱ组相比,Ⅰ组肝TG差异极显著(P＜0.01);Ⅲ组胸肌TG、肝TG有显著差异性(P＜0.05).(3)7周龄末鸡体重与对照组相比,Ⅱ组差异极显著(P＜0.01),Ⅲ组差异显著(P＜0.05);Ⅱ组料肉比比对照组极显著下降(P＜0.01).(4)肌肉中的营养成分,Ⅰ、Ⅱ组腿肌中粗脂肪比对照组极显著下降(P＜0.01),Ⅱ组腿肌中粗蛋白含量显著升高(P＜0.01).结论中药组方能不同程度地调整鸡脂质代谢,提高生产性能和改善鸡肉品质.在3个不同中药组方中,综合效果Ⅱ方最优.     

复方吡喹酮注射液防治羊脑多头蚴病的试验研究

为了获得复方吡喹酮注射液治疗羊脑多头蚴病的最佳治疗剂量,本试验应用复方吡喹酮注射液30、50、80 mg/kg BW三个剂量组对患羊脑多头蚴病的绵羊进行治疗,设80 mg/kg BW剂量的丙硫咪唑作为药物对照组.试验结果表明,30 mg/kg BW剂量组治愈率较低,为68.97%,不能达到治疗目的;50和80 mg/kg BW剂量对羊脑多头蚴均有很强的驱杀作用,对病羊的治愈率分别为91.84%和92.85%,但两组间差异不显著(P＞0.05);高、中剂量组(80、50 mg/kg BW)与低剂量组、药物对照组比较差异极显著(P＜0.01).50 mg/kg BW剂量为防治羊脑多头蚴病的最佳治疗剂量.     

外源复合酶对移地保护圈养马来熊日粮营养消化率的影响

利用外源复合酶对移地保护圈养的 9只马来熊日粮营养物质及能量消化率进行了测定 ,经单因子方差分析结果表明 ,在圈养马来熊日粮中添加一定量的外源复合酶 ,能提高马来熊对日粮营养物质的消化率 ,其中 ,添加 0 3%饲料量的酶能显著提高日粮粗蛋白的消化率(P <0 0 5) ;添加 0 5%的酶 ,能显著提高日粮粗纤维、粗蛋白质消化率 (P <0 0 5)。此研究结果可应用于马来熊的饲养中 ,提高其饲料报酬     

复方增茸剂对梅花鹿茸产量与品质的影响

选择体质、体型、健康状况、产量性能相接近的梅花鹿50头，随机分为2组即试验组与对照组，将复方增茸剂混全饲料中投喂，每日1次，连续饲喂70d，观察该药对试验动物的影响。结果表明：应用复方增茸剂后，试验组鹿的血液中红细胞、血红蛋白、碱性磷酸酶、血钙和血磷量明显高于对照组，并且鹿茸中各种氨基酸的含量也明显高于对照组。该药具有促进造血机能，加快麂茸生长，提高鹿茸品质的作用。     

切屑卷曲的力学分析及其应用

在试验和理论分析的基础上，本文提出了复合卷曲的切屑比向上卷曲的切屑、当侧卷程度较大时比例向卷曲的切屑易于折断的观点，并且讨论了切屑产生复合卷曲及侧向卷曲的条件，这些对断屑槽的设计和使用有重要意义。     

用亚硫酸氢钠提取菲醌方法的改进

本文对采用亚硫酸氢钠提取菲醌的方法做了研究，实验表明此法是一种经济简便的有效方法。通过实验确定了提取所需的最佳摩尔比，从而为降低生产成本提供了实验依据。     

Comparative studies of strains of infectious bovine rhinotracheitis virus isolated from latently infected calves

Three strains (479 C, 778 TL, 982 LE) of infectious bovine rhinotracheitis (IBR) virus isolated from latently infected calves were compared with the prototype strain of IBR virus (LA strain) in studies which included restriction endonuclease analysis, experimental infection, and reciprocal cross protection tests in cattle. From the restriction endonuclease analysis it appeared that the 3 "latent" viruses were derived from the same isolate, and that it differed slightly from the LA strain. However, latency does not seem to have affected the pathogenicity or the immunogenicity of the virus. This is demonstrated by the identical clinical and virologic response of calves subjected to experimental infection with the various strains under study, and by the finding that when the LA strain and a "latent" strain (982 LE) were tested in cross protection tests in cattle, they proved to be mutually protective.     

中国山羊品种资源及其遗传多样性研究

本文论述了中国山羊的起源、品种遗传资源及其遗传多样性的研究进展。最新调查 显示中国的山羊品种达50个,其中43个为地方品种,4个培育品种,3个引入品种,许多品种 具有独特的生产性能或适应能力。大量研究表明,我国山羊遗传多样性较为丰富。     

哈茨木霉几丁质酶诱导及其对水稻纹枯病菌的拮抗作用

 在实验室条件下分别以几丁质和水稻纹枯病菌(Rhizoctonia solani)细胞壁作唯一碳源诱导哈茨木霉(Trichoderma harzianum)菌株NF9、TC3和P1产生几丁质酶,用硫酸铵沉淀法制备几丁质酶粗提液。上述木霉菌株内切几丁质酶活性(对胶体几丁质浑浊度的减少率)分别为79.8%、74.4%和76.0%,均显著高于非诱导的阳性对照。培养第5 d几丁质诱导的木霉菌株NF9和TC3内切几丁质酶活性显著高于由水稻纹枯病菌细胞壁诱导的酶活性。体外测定表明,通过诱导的木霉菌株TC3、NF9和P1几丁质酶粗提液对水稻纹枯病病菌的拮抗圈直径可达38、21和23 mm,与非诱导的阳性对照比较有显著性差异。对木霉几丁质酶拮抗作用的特点及生防应用进行了讨论。