H9N2 avian influenza virus is a zoonotic agent with a broad host range that can contribute genetic information to H5 or H7N9 subtype viruses, which are significant threats to both humans and birds. Thus, there is a great need for a vaccine to control H9N2 avian influenza. Three mutant viruses of an H9N2 virus A/chicken/Taixing/10/2010 (rTX-NS1-73, rTX-NS1-100, and rTX-NS1-128) were constructed with different NS1 gene truncations and confirmed by western blot analysis. The genetic stability, pathogenicity, transmissibility, and host immune responses toward these mutants were evaluated. The mutant virus rTX-NS1-128 exhibited the most attenuated phenotype and lost transmissibility. The expression levels of interleukin 12 in the nasal and tracheal tissues from chickens immunized with rTX-NS1-128 were significantly upregulated on day 3 post-immunization and the IgA and IgG antibody levels were significantly increased on days 7, 14, and 21 post-immunization when compared to chickens that received an inactivated vaccine. rTX-NS1-128 also protected chickens from challenge by homologous and heterologous H9N2 avian influenza viruses. The results indicate that rTX-NS1-128 can be used as a potential live-attenuated vaccine against H9N2 avian influenza.

猪圆环病毒2型(Porcine circovirus type 2,PCV-2)是近年来发现的一种较难控制的传染病.该疾病主要侵害哺乳仔猪、育肥猪及怀孕母猪[1],其特征性临床症状为患猪体质不良、皮肤苍白,引起的疫病包括仔猪断奶后多系统衰竭综合征(PMWS)、增生性坏死性肺炎(PNP)、猪皮炎与肾病综合征(PDNS)、猪呼吸系统疾病综合征(PRDC)、繁殖障碍、先天性震颤及肠炎等.PCV-2感染产生的免疫抑制极易引发其他病原混合感染或继发感染[1-2].目前,猪圆环病毒病在我国已普遍发生,表现为流行范围广、阳性率高、混合感染严重、种猪感染率高等特点,给我国养猪业造成严重的经济损失[3].目前,疫苗接种被认为是防控该病最有效的手段之一.

The pathogenicity and transmissibility of H9N2 influenza viruses has been widely investigated; however, few studies comparing the biological characteristics of H9N2 viruses isolated from different hosts have been performed. In this study, eight H9N2 viruses, isolated from chickens (Ck/F98, Ck/AH and Ck/TX), pigeons (Pg/XZ), quail/(Ql/A39), ducks (Dk/Y33) and swine (Sw/YZ and Sw/TZ) were selected, and their biological characteristics were determined. The results showed that all H9N2 viruses maintained a preference for both the avian- and human-type receptors, except for Sw/TZ, which had exclusive preference for the human-type receptor. The viruses replicated well in DF-1 and MDCK cells, whereas only three isolates, Ck/F98, Ck/TX and Sw/TZ, could replicate in A549 cells and also replicated in mouse lungs, resulting in body weight loss in mice. All H9N2 viruses were nonpathogenic to chickens and were detected in the trachea and lung tissues. The viruses were shed primarily by the oropharynx and were transmitted efficiently to naïve contact chickens. Our findings suggest that all H9N2 viruses from different hosts exhibit efficient replication and contact-transmission among chickens, and chickens serve as a good reservoir for the persistence and interspecies transmission of H9N2 influenza viruses.

Background: H5N1 highly pathogenic avian influenza (HPAI) has raised global concern for causing huge economic losses in poultry industry, and an effective vaccine against HPAI is highly desirable. Live attenuated influenza vaccine with trunctated NS1 protein as a potential strategy will be extremely useful for improving immune efficacy.Methods: A series of H5N1 avian influenza virus reassortants harboring amino-terminal 48, 70, 73, and 99 as in NS1 proteins, along with a modified low pathogenic HA protein was generated, and named as S-HALo/NS48, S-HALo/NS70, S-HALo/NS73, and S-HALo/NS99, respectively. In addition, their biological and immunological characteristics were further analyzed.Results: The viruses S-HALo/NS70, S-HALo/NS73, and S-HALo/NS99, but not S-HALo/NS48, had a comparable growth property with the full-length NS1 virus, S-HALo/NSFu. Mice and chickens studies demonstrated that the viruses with truncated NS1 protein were further attenuated when compared to the virus S-HALo/NSFu. Vaccination with the virus S-HALo/NS73 in chickens induced significant cross protection against homologous Glade 2.3.4 H5 virus and heterologous Glade 7.2, 2.3.2.1, and 2.3.4.4 H5 viruses.Conclusion: A 70-aa amino-terminal fragment of NS1 protein may be long enough for viral replication. The recombinant virus S-HALo/NS73 is a broad-spectrum live attenuated H5N1 avian influenza vaccine candidate in chickens. (C) 2015 Elsevier Ltd. All rights reserved.

The location and number of glycosylation in HA proteins exhibit large variations among H5 subtype avian influenza viruses (AIVs). To investigate the effect of glycosylation in the globular head of HA on the pathogenicity and antigenicity of H5N1 AIVs, seven rescued AIVs differing in their glycosylation patterns (144N, 158N and 169N) within the HA globular head of A/Mallard/Huadong/S/2005 were generated using site directed mutagenesis. Results showed that loss of glycosylation 158N was the prerequisite for H5 AIV binding to the α2,6-linked receptor. Only in conjunction with the removal of the 158N glycosylation, the H5 AIVs harboring both 144N and 169N glycosylations obtained an optimal binding preference to the α2,6-linked receptor. Compared with the wild-type virus, growth of viruses lacking glycosylation at either 158N or 169N was significantly reduced both in MDCK and A549 cells, while replication of viruses with additional glycosylation 144N was significantly promoted. Mutant viruses with loss of 158N or 169N glycosylation sites showed increased pathogenicity, systemic spread and pulmonary inflammation in mice compared to the wild-type H5N1 virus. In addition, chicken studies demonstrated that inactivated de-glycosylation 169N mutant induced cross-reaction HI and neutralization antibody against various clades of H5N1 AIVs. Moreover, this type of glycan pattern vaccine virus provided better cross-protection in chickens compared to wild-type vaccine virus. Thus, the glycosylation alteration of HA should be considered in the global surveillance and vaccine design of H5 subtype AIVs.

The present invention relates to H9N2 avian influenza virus NS1 gene deletion candidate live attenuated vaccine strain rTX-NS1-128 constructing method and application. The H9N2 subtype avian influenza virus NS1 gene deletion candidate live attenuated vaccine strain rTX-NS1-128, is A / chicken / Taixing / 10 / 2010TX female parent strain, the length of the NS1 gene is deleted, such that the NS1 protein retaining only shown in SEQ ID NO.15 as 128 amino acids. The vaccine candidate can be copied in the trachea, contact transmission occurs, safety. The candidate vaccine strain can be used alone as an effective tool H9 subtypes of avian influenza, can also be used in combination with inactivated vaccine, provide a more exact immune protection. It will play a very important role in H9 subtype of avian influenza prevention and control.

H9N2 avian influenza virus (AIV) evolves rapidly in both genovariation and antigenicity. It is essential to monitor the change of antigenicity, in particular in the hemagglutinin (HA) protein. Here we reported the selection of antigenic variants from A/Chicken/Shanghai/F/98 (H9N2) and A/chicken/Taixing/10/2010 (H9N2) viruses using HA-specific monoclonal antibodies (MAbs). Based on the reactivity of these variant and wild-type strains with the MAbs, we identified 6 critical amino acid positions (92, 145, 166, 167, 168, and 197) in the H9 antigenic sites, including the position 92 that has never been reported. Among AIVs originated from chicken in mainland China, the rates of Gly and Arg at position 92 within BJ/94-like (A/chicken/Beijing/1/1994) lineage viruses were 62.2% (28/45) and 37.8% (17/45), respectively; whereas the rates of Gly and Arg at position 92 within Y280-like (A/duck/Hong Kong/Y280/97) lineage viruses were 0.3% (2/670) and 99.1% (673/679), respectively. Our study suggests that G92R mutation together with other identified antigenic sites may serve as molecular markers for H9N2 virus evolution, and may aid improving AIV vaccine effectiveness.

Since 2003, H5N1-subtype avian influenza viruses (AIVs) with both a deletion of 20 amino acids in the stalk of the neuraminidase (NA) glycoprotein (A-) and a deletion of five amino acids at positions 80 to 84 in the non-structural protein NS1 (S-) have become predominant. To understand the influence of these double deletions in the NA and NS1 proteins on the pathogenicity of H5N1-subtype AIVs, we selected A/mallard/Huadong/S/2005 as a parental strain to generate rescued wild-type A-S- and three variants (A-S+ with a five-amino-acid insertion in the NS1 protein, A+ S- with a 20-amino-acid insertion in the NA stalk, and A+ S+ with insertions in both NA and NS1 proteins) and evaluated their biological characteristics and virulence. The titers of the AIVs with A- and/or S- replicated in DEF cells were higher than that of A+ S+, and the A-S- virus exhibited a replication predominance when co-infected with the other variants in DEF cells. In addition, A-S- induced a more significant increase in the expression of immune-related genes in peripheral blood mononuclear cells of mallard ducks in vitro compared with the other variants. Furthermore, an insertion in the NA and/or NS1 proteins of AIVs resulted in a notable decrease in virulence in ducks, as determined by intravenous pathogenicity index, and the two insertions exerted a synergistic effect on the attenuation of pathogenicity in ducks. In addition, compared with A+ S+ and A+ S- the A-S+ and A-S- viruses that were introduced via the intranasal inoculation route exhibited a faster replication ability in the lungs of ducks. These data indicate that both the deletions in the NA stalk and the NS1 protein contribute to the high pathogenicity of H5N1 AIVs in ducks.

近期,江苏镇江地区某雏鹅群中发生以严重下痢,呼吸困难,高死亡率,小肠卡他性、纤维素性坏死性肠炎为特点的传染病,疑似小鹅瘟病毒感染.为进一步确诊,对送检的病料用无小鹅瘟母源抗体的鹅胚进行病毒分离鉴定及PCR检测.试验结果显示,接种病料的鹅胚尿囊膜增厚,死亡胚体充血和出血,胚肝出血,心脏呈白瓷色；PCR成功扩增出与预期大小相符的550 bp目的片段.对PCR产物测序及BLAST分析表明,扩增的VP3基因与CHv-1基因同源性为100％,由此确定该鹅群感染了小鹅瘟病毒.

H5N1 avian influenza virus (AIV) undergoes rapid evolution, and its antigenicity needs to be constantly evaluated in order to update the vaccine strain. In this report, a clade 7.2 AIV isolate named A/Chicken/Huadong/4/2008 (DT) is identified. Antigenic analysis revealed that DT had a significant low cross-reactive HI titre with antiserum against a clade 7 representative AIV, A/Chicken/Shanxi/2/2006 (Re-4). Animal experiments demonstrated that the Re-4 + Re-5 vaccine provided 80% protection against DT challenge in chickens. Antisera cross-reactivity showed that a mutant with a change of residues 129, 139, 140 in site A in the HA protein had reduced reactivity with DT antiserum and increased reactivity with Re-4 antiserum. Furthermore, residue Leu129 in site A of the HA protein was confirmed to be critical for maintenance of the reactivity with the DT antiserum, and Asn140, possessing a new glycosylation site, was confirmed to be critical for reducing reactivity with the Re-4 antiserum. These results imply that there is an antigenic drift within clade 7 viruses, and insertion and glycosylation of amino acid residues in site A of the HA protein may contribute to the antigenic variation.

<正>自古以来,野禽就生活于自然光照之下,每年春季,当日照逐渐延长,增加光照之后,母禽开始产蛋孵化、繁殖后代。可见,光照是鸡赖以生存的环境中最重要的因素之一,对鸡的影响极大,特别是蛋鸡对光源性质和光照强度都有着特殊的敏感性和

<正>今年冬季的燃油价格甚高(当前大约是每加仑1.60美元),这对于肉鸡生产商来说也成为了有史以来所必须支付的最高的一笔花费在禽舍增温设备燃料上的开支c。因而,一些生产商或许会试图通过减短鸡舍预热时间或降低雏鸡孵化温度来减少增温所耗的燃油,从而减缓油价的压力。然而事实上,这些节省下来的开支却远不及由于低温造成的肉仔鸡生产性能

The purpose of this paper is to provide an overview of the mechanism of methane production in rumen, and explain the effective strategies to mitigate methane emission, which ultimately serve to minimize the harmful impacts on the environment without bringing about much adverse effects on the production performance of livestock.

120头育肥后期杜(长本)去势三元杂交商品猪均分为3组,每组40头,组内设4个重复,每个重复10头,公母各半。分别饲喂以基础日粮(组I)、基础日粮+0.01%XOS(组Ⅱ)、基础日粮+0.03%XOS(组Ⅲ)。结果表明:组Ⅲ的胴体瘦肉率比组Ⅰ和组Ⅱ高1.52(P<0.05)和1.77个百分点(P<0.05),胴体中骨比率高1.56(P<0.05)和0.53(P<0.05)个百分点,脂肪比率低2.65(P<0.05)和2.69个百分点(P<0.05),6、肋膘厚降低0.59cm(P<0.05)和0.3cm(P<0.05),饲料中添加XOS可使7肉色改善,肌肉pH、嫩度、肌内脂和系水力各组间差异不显著。

By explaining the mechanism of ammonia production, its harmful impacts on the livestock and poultry industry as well as a series of endogenous strategies of mitigating its emission, we try to discuss and provide some useful methods to minimize the its adverse influences in this paper.

The distribution of vasoactive intestinal peptide(VIP) positive cells in the gastrointestinal tract of Laiwu black goat was compared and observed.The immunohistochemical method was used to show the distribution of VIP in the layers of various sections of gastrointestinal wall.The VIP positive cells were mostly distributed in the cardia,and then the colon,jejunum,pylorus,caecum,rectum and fundus;in the duodenum,ileum and esophagus,the VIP positive cells were not found.Moreover,the forms of VIP cells are diverse: some have the shapes as ellipse or cone,some extend up to other cells nearby,and others to epidermic cells.