热敏电阻冰点仪法测定生鲜牛乳中冰点的研究

利用热敏电阻冰点仪法测定生鲜牛乳中的冰点,对该方法的重复性、灵敏度以及掺水掺盐对生鲜牛乳冰点值的影响等方面进行了研究.此方法的检测极限值为2.4 m℃.     

规模化舍饲养羊常见疾病防治

舍饲养羊的发展规模与内部结构都取得良好的发展成就,在规模化舍饲养羊方面,养殖技术、养殖规模都得到长足的进步与提升。在我国诸多政策支持下,辽宁锦州地区的舍饲养羊的发展也逐渐呈现出规模化、标准化发展水平,使舍饲养羊常见疾病得到一定的控制,并采取积极的宣传措施,使农民规模化舍饲养羊的整体标准不断提升。因此,该文主要对规模化舍饲养羊常见疾病的防治进行分析。     

硫酸新霉素可溶性粉在靶动物猪的安全性研究

为了客观评价硫酸新霉素可溶性粉对靶动物猪临床应用的安全性,将32头仔猪随机分为4组,每组8头,分别设1倍、3倍、5倍临床推荐剂量组和空白对照组,连续混饮硫酸新霉素可溶性粉15 d,通过检测各组受试猪的临床表现、血液常规指标、血清生化指标、尿液常规指标及病理学变化等评价其临床用药的安全性。结果:硫酸新霉素可溶性粉以5倍临床推荐剂量内应用于靶动物猪后,对其临床症状、体重、血常规、血生化及尿常规等指标没有显著影响,解剖学及病理组织学检查也未见任何病理变化,说明硫酸新霉素可溶性粉以1倍、3倍、5倍临床推荐剂量应用于靶动物猪是安全的。     

One year's study of dynamic and evolution of types I and II PRRSV in a swine farm

This study was to investigate dynamic and evolution of PRRSV in a seed-stock farm by monitoring PRRSV status from 11 June 2009 to 4 August 2010. For laboratory test, around 18-24 umbilical cords from farrowed sows and 5-95 sera from nursery and grow/finish pigs were submitted around every 2 weeks interval during the study. The submitted samples were tested for PRRSV using IDEXX PRRS 2XR ELISA kit, RT-nested PCR. The PRRSV-positive samples were further sequences based on ORF5 and analyzed using MEGA 3.1 program and Beast 1.5.4 package. The surveyed farm was first infected with type II PRRSV but it was infected newly with type I PRRSV of unknown origin, showing rapid substitution to type I PRRSV as a dominant strain in 2 weeks. The type I PRRSV was first detected from umbilical cord of a farrowed sow in 12 January 2010, and secondly from nursery pigs in 26 January 2010. Although sudden increase of mean S/P ratio was found in grow/finish pigs around 2 months earlier than first type I PRRSV detection, no type I PRRSV viremia was found. Thirty three ORF5 full sequences from 14 type II to 19 type I PRRSVs were obtained chronologically in this farm and the genetic characteristics and evolution rates of those sequences were analyzed. The substitution rates (/site/day) of two types were 4.03×10(-5) (type I), 3.09×10(-5) (type II), respectively, which was more frequent than previous reports. The calculated divergence time of type I PRRSV was consistent with the time when the sudden elevation of serum IgG in grow/finish barn was first observed. This study provided fundamental data for type I PRRSV dynamic in a previously type II PRRSV-infected farm and suggested grow/finisher barn could be a primary site for PRRSV introduction.     

猪某些免疫指标及其与部分生产性状关系的研究

实验测定了哈白、杜洛克猪３月龄和５月龄的总数Ｅ－玫瑰花环形成细胞百分率、活性Ｅ－玫瑰花环形成细胞百分率、淋巴细胞转化率、血清ＩｇＧ含量及５月龄接种布氏杆菌猪型二号苗后７、２１、３５６的特异性抗体滴度，对这些免疫指标及其与部分生产性状的关系进行了分析，旨在为猪的抗病育种提供依据。实验结果表明：（１）３月龄和５月龄几个免疫指标均存在品种差异，哈白猪显著地高干杜洛克猪；（２）３月龄与５月龄间所测细胞免疫指标无显著差异，但５月龄血清ＩｇＧ含量显著高于３月龄血清ＩｇＧ含量；（３）哈白与杜洛克猪对布氏杆菌疫苗的抗体应答能力存在显著差异；（４）所测定的细胞免疫指标间大多表现正的相关，体液免疫指标间亦表现正的相关，而细胞免疫指标和体液免疫指标间大多具有较弱的相关；（５）所测定的几个免疫指标与生产性状间大多具有较弱的相关。     

乳铁蛋白的生物学功能及其基因工程研究进展

乳铁蛋白是一种具有多种生物活性的糖蛋白。本文主要就乳铁蛋白的生物学功能及其基因工程研究进展作一综述。     

添加甲酸对白花草木樨青贮品质的影响

在收获后经过0、8和30h晾晒的初花期草木樨(干物质含量分别为27.36%、38.69%和44.98%)原料中,加入甲酸(添加量为2.5、4.0和5.5ml/kg)进行青贮。结果表明,添加甲酸能使草木樨青贮料氨态氮含量降低,并保存较多的可溶性糖;添加甲酸4.0ml/kg对三个干物质水平草木樨青贮均有良好效果,但以干物质含量27.36%组效果最好。     

巡逻犬盘查监控能力训练实验研究

<正>盘查是警察巡逻勤务中运用最多见且特别重要的手段。在盘查中执勤民警与工作对象具有遭遇性,并且是面对面地、直接地进行较量,盘查时被盘查人对执勤民警造成伤害或脱逃的情况屡见不鲜。将巡逻犬运用于巡     

Efficacy of a piglet-specific commercial inactivated vaccine against Porcine circovirus type 2 in clinical field trials

The efficacy of a piglet-specific inactivated Porcine circovirus type 2 (PCV2) vaccine was evaluated with clinical field trials, as recommended by the Republic of Korea’s Animal, Plant & Fisheries Quarantine & Inspection Agency. Three farms were selected on the basis of their history of postweaning multisystemic wasting syndrome. On each farm 60, 1-week-old pigs were randomly allocated to 1 of 2 treatment groups: vaccination at 1 and 3 wk of age or no vaccination. The 2-dose schedule of vaccination with inactivated PCV2 vaccine improved the average daily weight gain from birth to 16 wk of age, the PCV2 load in the blood, and the frequency and severity of lymph node lesions. Inactivated PCV2 vaccine seems to be very effective in controlling PCV2 infection under field conditions.     

日粮添加镁、硒、铬对热应激肉仔鸡血清生化和血液流变学的影响

试验旨在研究热应激情况下镁、硒、铬联合添加对肉仔鸡血清生化指标和血液流变学的影响。选用240只1日龄AA肉公鸡,随机分为4个处理,每个处理6个重复。T1为常温对照组,T2、T3、T4为热应激组。T1、T2饲喂基础日粮,T3、T4在基础日粮中分别添加镁、硒、铬2000、1.5、1.5mg/kg和4000、3.0、3.0mg/kg。结果表明:T3、T4组热应激鸡只死亡率显著降低,血清TP、ALB、GLOB、HDL水平显著升高(P0.05),GLU、BUN、TC含量显著降低(P0.05)。同时,T3、T4组的GPT、CK酶活力及低切变率下的全血黏度均显著降低(P0.05)。试验表明,联合添加镁、硒、铬能有效改善热应激肉鸡的血液生化和血液流变学指标,减轻热应激对机体的损伤,从而降低鸡只死亡率。