鸡传染性法氏囊病野毒株的分离鉴定

从患传染性法氏囊病(IBD)病鸡中分离出一株IBD病毒(IBDV)。该病毒是一株IBDV超强毒株,可使10周龄健康鸡100%发病,83.7％死亡。死亡鸡具有TBD的典型病变。     

传染性法氏囊病病毒的分离与鉴定

从中国广东省发生传染性法氏囊病的鸡场分离了8株传染性囊病病毒(Infectious bursal disease virus,IBDV)毒株,运用RT-PCR对分离毒株进行了鉴定,测定了8个分离株的ELD50以及其对SPF鸡的致死率。结果表明:这8株分离毒对SPF鸡的致死率均等于或超过60%,属于超强毒。运用RT-PCR方法对分离毒株进行了鉴定并对各毒株VP2基因高变区进行扩增测序,分析结果表明:这8株分离株均为IBDV超强毒株,同时也说明当前在广东省引起鸡传染性法氏囊病的主要毒株类型多为超强毒IBDV。     

山西省鸡传染性法氏囊病病毒的分离鉴定

为了解山西省鸡传染性法氏囊病病毒(IBDV)流行毒株的遗传变异规律,将近5年来采集自山西不同地区发病鸡群的法氏囊组织病料,通过接种易感雏鸡分离出15株IBDV。用绒毛尿囊膜接种法测定鸡胚半数致死量,其ELD50在10~(-2.18)~10~(-2.91);测定所有分离株对非免疫鸡的致死率,结果为63.3%~86.7%,属于超强毒株;利用RT-PCR扩增病毒VP2基因并进行序列分析。结果表明,所分离的15株病毒均具有传染性法氏囊病病毒超强毒株的主要分子特征,即222A(WS2为S)、249Q、254G、256I、279D、284A、294I、299S及七肽区SWSASGS,综合其对非免疫鸡的致死率,确认所有分离毒株属于超强毒病毒株。说明在山西省境内存在传染性法氏囊病病毒超强毒株。     

传染性法氏囊病病毒强毒株HB／11的分离与鉴定

2011年8月,从河南省疑似传染性法氏囊病鸡群采集病料,通过鸡胚接种、琼脂扩散试验和RT-PCR等方法,证实分离的病毒为传染性法氏囊病病毒（Infectiousbursaldiseasevirus,IBDV）,命名为HB／11株。序列分析表明,HB／11株VP2基因的核苷酸序列与GenBank中发表的部分国内外IBDV超强毒株VP2基因序列相似性在99％左右;HB／11株VP2高变区基因含有七肽基序为SWSASGS,在222、253、256、279、284、294和299位上的氨基酸残基分别是A、Q、I、D、A、I和S,具有IBDV强毒的分子特征。动物回归试验表明,30日龄鸡群接种该毒株后引起鸡群发病率为100％,死亡率为70％,剖检可见鸡传染性法氏囊病典型病变。因此该病毒为IBDV强毒株。     

鸡传染性法氏囊病病毒地方流行毒株的免疫原性

从河北省一些发病鸡场分离到JD1～JD10共10株鸡传染性法氏囊病病毒(IBDV)毒株,用IBD标准阳性血清以琼扩试验进行了初步鉴定.并进行了IBDV分离物及其鸡胚适应毒免疫原对标准强毒IBDV-BC6/85株免疫保护试验,D78弱毒疫苗对IBDV各分离毒株的免疫保护试验以及分离毒株间交互免疫保护试验.结果表明,D78疫苗对JD2,JD5和JD10 IBDV分离株的保护率较低,分别为40%、50%和60%.分离毒株JD5、JD2及其鸡胚传代物E-JD2对强毒株的免疫保护率可达100%.交互免疫保护试验表明,JD2对其余各分离株的免疫保护指数达到80%以上,对标准强毒株和地方分离株均可产生有效免疫保护.     

鸡传染性法氏囊病病毒SD株毒力测定

从一个免疫失败鸡场中分离到一株鸡传染性法氏囊病病毒野毒株,命名为SD株.经血清学试验、鸡胚接种、病毒形态观察等证实了分离物为鸡传染性法氏囊病病毒(IBDV).测定病毒效价ELD50达到10-6.5/0.2 mL;动物回归试验表明,该SD株接种4周龄鸡后引起鸡群发病率为100%,病死率达85%,剖检可见法氏囊呈"紫葡萄样...     

鸡传染性法氏囊的治疗

鸡传染性法氏囊病(IBD)又称鸡传染性腔上囊病。传染性法氏囊病毒属双RNA病毒科,包括两个血清型。根据毒株的致病性,IBDV可分为无致病力(血清II型)、弱毒力(疫苗株)、经典强毒、变异株和超强毒株。血清II型株不引起鸡的法氏囊损伤和鸡只死亡。弱毒力株不引起死亡,但根据其毒力的差异对法氏囊造成不同程度的损伤。经典强毒株引起     

蛋鸡源传染性法氏囊病病毒变异株的分离、鉴定及攻毒保护试验

为研究已免疫传染性法氏囊病(IBD)疫苗的蛋鸡群发生非典型IBD的原因,从2019年检测为传染性法氏囊病病毒(IBDV)阳性的病料中进行病毒分离,并对分离株进行生物学特性测定。结果显示,从5份阳性病料中分离到5株IBDV,5株分离株均不致死SPF鸡,剖检后仅发现法氏囊萎缩,无其它典型病变;对5株分离株VP2基因的遗传进化分析发现,5株IBDV均属于新型变异株分支,而且5株IBDV分离株均具有IBDV变异株的特征性氨基酸位点222T、249K、286I、318D,另外也具有新型变异株的独特氨基酸位点221K、252I和299S;攻毒保护试验表明,使用当前的IBD灭活疫苗对IBDV经典强毒株可提供100%保护,对2019年分离的IBDV流行株保护率为50%~80%。研究提示,IBDV新型变异株已在部分蛋鸡群中流行,而且当前疫苗不能对鸡群提供完全保护,有必要研发用来预防IBDV新型变异株感染的疫苗。     

鸽源传染性法氏囊病病毒的分离鉴定及其A、B节段序列扩增

目的:分离鉴定鸽源传染性法氏囊病病毒(IBDV),扩增其基因组A、B节段cDNA.方法:采用SPF鸡胚尿囊腔接种分离IBDV,RT-PCR鉴定并扩增A、B节段全基因组DNA,进行同源性比较,初步分析分离株序列特征.结果:该分离株经RT-PCR特异性鉴定引物鉴定为强毒株,与强毒株相比,核苷酸序列同源性达97%,氨基酸序列同源性99%.     

鸡传染性法氏囊病病毒秦皇岛株的分离鉴定

将秦皇岛某养鸡场疑似为传染性法氏囊病的病死鸡进行剖检,为了对该疑似病例进行确诊,并进行流行病学研究,经对流免疫电泳,对采集的病料进行病毒的分离,阳性法氏囊病料进行病毒RNA的提取,采用套式RT-PCR对病毒的VP2高变区进行扩增,分析氨基酸序列。结果表明,该分离株为传染性法氏囊病病毒(IBDV),被检毒株与GenBank报道的标准超强毒株OKYM、UK661、DV86同源性高达100%,与V3、V2亲缘关系较近。动物回归试验可使健康鸡100%发病,病死率80%。表该分离株为鸡传染性法氏囊病病毒超强毒株。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

獭兔睾丸的组织学观察

家兔作为一种实验动物 ,推动了繁殖技术的发展。本试验通过对不同年龄公獭兔的睾丸进行组织学观察、测定 ,研究精子的发生规律 ,为系统地进行繁殖生理工作提供依据。1　材料与方法选 60日龄、75日龄、90日龄 3个年龄公獭兔各5只 ,用外科手术法摘取两侧睾丸 ,放入 Bouin氏液中固定 ,二甲苯透明 ,石蜡包埋 ,切成 5～ 8μm切片 ,H.E.染色。在显微镜下观察 ,并进行定量组织学指标测定及差异性比较。2　结果和讨论2 .1　睾丸定量组织学指标的测定结果　见表 1。表 1　獭兔睾丸定量组织学指标　　　μm,个 /精细管60日龄 75日龄 90日龄曲细精管…     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.