Feline coronavirus (FCoV) poses a significant threat to the lives of cats, and there is currently no commercial vaccines available. In the present study, a vaccine was developed using a human type 5 adenovirus vector to express the FCoV-I S protein (rAd5-FCoV-S) to induce the immunogenicity of rAd5-FCoV-S through oral and intramuscular immunization in mice and cats. Both vaccination methods stimulated a higher IgG antibody response. However, oral vaccination led to a significantly higher SIgA antibody level, which was 4.8 times and 2.4 times greater than that induced by intramuscular vaccination in mice and cats, respectively, with the highest level reaching 1:128. In addition, oral vaccination increased the count of IFN-γ-producing and IL-4-producing splenocytes in mice, effectively boosting cellular immune responses. Challenge protection experiments in cats showed that oral vaccination with rAd5-FCoV-S provided 100 % protection compared to a survival rate of only 33 % for unvaccinated cats. Compared to the PBS group, oral rAd5-FCoV-S administration substantially decreased the FCoV viral load within the feces, rectal tissues, and colon tissues of cats. Hematoxylin and eosin (HE) staining and immunohistochemical analysis of rectal and colonic tissues revealed that cats in the oral group exhibited minimal intestinal damage, whereas PBS cats presented significant inflammatory cell infiltration and shedding of intestinal epithelial cells. These findings demonstrate that oral administration of rAd5-FCoV-S induces a robust humoral immune response and a strong cell-mediated immune response in cats, thereby conferring immunity against FCoV infection.

IntroductionPorcine reproductive and respiratory syndrome (PRRS), caused by porcine reproductive and respiratory syndrome virus (PRRSV), occurs frequently in China, and severely hinders the healthy development of the pig farming industry.MethodsTo determine the genetic diversity and epidemiological characteristics of PRRSV strains in Sichuan Province, we collected 499 clinical samples suspected of PRRSV infection from 101 pig farms in 19 cities from 2023 to 2024.Results and DiscussionAmong the 499 samples, 162 were positive for PRRSV, with a total prevalence of 32.46% according to RT-qPCR. Among the 101 pig farms, 55 were positive farm, resulting in a rate of 54.46%. Further analysis of the complete ORF5 gene sequences of 56 PRRSV strains revealed that they could be classified into six lineages: PRRSV-1, lineage 8 (HP-PRRSV), lineage 5 (Classical PRRSV), lineage 1.8 (NADC30-like strain), lineage 1.5 (NADC34-like strain), and lineage 3.5 (QYYZ-like strain). Notably, both the lineage 8 and PRRSV-1 strain were detected in the same sample, indicating the presence of mixed infection. This study revealed the coexistence of multiple lineages of PRRSV in Sichuan Province, with the lineage 1.8 emerging as the predominant epidemic lineage. The concurrent prevalence of multiple lineages underscores the importance of selecting matching vaccines on the basis of locally prevalent strains and the need for continuous epidemiological monitoring of PRRSV.

Glyphosate, a prevalent herbicide, has raised concerns due to its potential ecological impact, especially on aquatic ecosystems. While it is crucial for managing agricultural productivity, its inadvertent effects on non-target aquatic species like the red swamp crayfish, Procambarus clarkii, are not fully understood. In the present study, the neurotoxicity, oxidative stress, and immune suppression of glyphosate on P. clarkii were investigated. Sublethal glyphosate exposure (5, 10 and 20 mg/L) for 96 h was found to significantly decrease AChE activity in both brain and hepatopancreas, correlating with reduced foraging efficiency and increased turnover time. Oxidative stress was evident through increased lipid peroxidation (LPO) and malondialdehyde (MDA) levels and altered antioxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). In addition, the total antioxidative capacity (T-AOC) was inhibited at 10 and 20 mg/L of glyphosate exposure. Immune assays revealed a decrease in total hemocyte counts (THC) and suppression of key immune enzyme activities and transcriptional expressions at higher concentrations, suggesting compromised immune defenses. The findings demonstrate that glyphosate can induce considerable neurotoxic and immunotoxic effects in P. clarkii, disrupting essential physiological functions and behavior.

2022年3月,四川省西昌市某乡镇山羊发生了口唇病变为特征的疾病.采集患病山羊的口腔分泌物及口疮黏液提取总DNA并进行PCR扩增及测序分析确诊该羊场感染了羊口疮病毒.这是西昌省首次检测到并报道羊口疮病,可为西昌市做好该病的防控和公共卫生安全提供一定的参考.

2022年7月西昌市某乡镇山羊出现呼吸困难、喘气、咳嗽、精神萎靡、消瘦、死亡等症状,为明确发病原因,进行了现场流行病学调查、病理解剖和实验室PCR扩增相结合的方法诊断试验,并根据确诊结果进行防控和治疗.实验室诊断结果表明,该山羊的绵羊肺炎支原体、多杀性巴氏杆菌、溶血性曼氏杆菌、羊副流感3型病毒核酸检测结果均为阴性,山羊丝状支原体核酸检测呈阳性,因此该病例被诊断为山羊丝状支原体感染.通过对患病山羊采取隔离治疗、环境消毒、加强饲养管理等综合防治措施,病情得到了有效控制.本研究为西昌市在临床上科学防控山羊呼吸道疾病提供了指导和借鉴.

为确定某羊场一例羊皮下脓肿病的病原,将病料样本接种于TSA固体培养基进行病原分离,然后对分离菌进行革兰氏染色镜检、生化鉴定、药敏试验和生物信息学分析.结果分离到1株革兰氏阳性球菌和1株革兰氏阴性短杆菌,经生化鉴定以及16SrDNA PCR扩增、测序、同源性分析,鉴定该分离菌株为金黄色葡萄球菌和溶血性曼氏杆菌;2株细菌对头孢曲松、链霉素、四环素、多西环素、左氧氟沙星等多种药物敏感.

潘氏细胞位于小肠隐窝(又名小肠腺)基底部,是高度特化的分泌性上皮细胞,能够分泌α-防御素、溶菌酶、分泌性磷脂酶A2等抗菌物质.潘氏细胞在维持肠道稳态和调节小肠微生物群等方面具有重要作用.本文综述了潘氏细胞的发生与特性、α-防御素的重要作用,潘氏细胞与畜禽肠道炎症及功能障碍的关系.

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide. In 2018-2022, we investigated the presence of HEV RNA in 1233 stool samples collected in the Qinghai-Tibetan Plateau, including humans (16), Tibetan pigs (624), yaks (312), sheep (267), and dogs (14). HEV RNA was only detected in Tibetan pig faecal samples (18.27%, 114/624). To perform molecular characterization of HEV strains in Tibetan pigs, we obtained 21 complete HEV genome sequences between 2018 and 2022. Sequence comparisons showed that 21 HEV strains from Tibetan pigs shared the mean nucleotide identities with the reference HEV strains ranging between 82.9% and 94.9% and 89.3% and 92.1% similarities with human HEV strains. Phylogenetic analysis confirmed that all HEV strains were genotype 4, closely related to human HEV strains. Sequence recombinant analysis showed five potential recombinant strains identified in this study, of which SWU/D18/2018 (GenBank No. MK410044) was recombinant with human and swine HEV strains, located 6509-6878 nt from the recombination point. Based on the Bayesian evolutionary trees, we found that most HEV strains diverged later than human HEV (16 Tibetan pig HEV strains diverged later than 1979, and seven human HEV strains diverged earlier than 1979). Therefore, we speculated that the prevalence of HEV 4 in Tibetan pigs possibly originated from humans in the Qinghai-Tibetan Plateau.

为有效防控四季常见猪呼吸道疾病,并减少抗菌素的使用量,采取中(兽)医"消除致病因、四季辨证用药、中西医结合、治未病"的综合防控方案.对中兽医辨证法应用于猪呼吸道疾病的防治,进行了阐述.

2021年3月四川省西昌市某猪场育肥猪出现明显的呼吸道症状.为明确发病原因,对病死猪进行了病理剖检、用特异性引物进行PCR分析对病原学检测及对分离菌进行药敏试验.剖检表明,肺有明显的出血、充血;PCR检测结果表明,猪圆环病毒2型与猪巴氏杆菌为阳性;药敏试验结果表明,分离菌对头孢曲松、诺氟沙星、环丙沙星、丁胺卡那敏感.根据检测结果调整猪场免疫程序,对猪群紧急免疫,同时用敏感药物进行全群保健和个体治疗,快速控制了疫情,降低了猪群的死亡率,为猪场挽回了损失.本研究为该场临床准确用药提供科学指导,对猪呼吸道疾病综合征的准确诊断以及治疗提供一定的理论依据.

圆环病毒是一类无囊膜单链环状DNA病毒,属于圆环病毒科,包括圆圈病毒属、圆环病毒属.鸭圆环病毒(DuCV)目前被列为圆环病毒属的暂定种,DuCV无囊膜,呈二十面体对称,直径为14～17nm,基因组大小为2kb. 感染DuCV的病鸭在临床上表现为发育迟缓、体重减轻及羽毛杂乱等.从病理学分析,感染DuCV鸭的免疫组织受损,导致淋巴细胞萎缩、凋亡甚至坏死等,从而让鸭免疫力降低,对其他疾病易感,容易发生继发感染和多重感染,DuCV与鸭大肠杆菌、鸭疫里默氏杆菌(RA)、鸭病毒性肝炎Ⅰ型病毒(DHV)等混感率较高.

犊牛腹泻是犊牛常见的疾病之一,影响犊牛生长发育和成活率.2021年1月,西昌市某奶牛场发生犊牛腹泻,为确定病因,笔者运用PCR和RT-PCR方法对该场22份犊牛腹泻粪便样本进行10种腹泻病原检测,结果得出:22份样本均检测到牛病毒性腹泻/黏膜病病毒(BVDV);16份样本显示牛诺如病毒(BNoV)阳性;12份样本显示纽布病毒(NeV)阳性;8份样本显示牛轮状病毒(BRV)阳性;4份样本为牛细小病毒(BPV)阳性;牛冠状病毒(BCoV)和环曲病毒(BToV)各1份样本显示阳性;而大肠杆菌、沙门氏菌、巴氏杆菌等细菌性病原均未检出.本调查结果表明引起该场犊牛腹泻的原因主要是多种病毒的混合感染,其中牛病毒性腹泻/黏膜病病毒的感染率高达100％.

目前,大多数基层防疫组织存在着"线断、网破、人散"的现状,如何稳定并不断强化基层动物防疫队伍建设,是巩固凉山州当前非洲猪瘟等动物疫病防控工作成效、确保不发生区域性重大动物疫情的基础和关键,也是凉山州恢复生猪产能、促进养殖产业健康发展、保障畜禽肉产品供应和质量安全的必要前提.

为了解2021年上半年凉山州高致病性禽流感等重大动物疫病的预防免疫效果,本试验对高致病性禽流感((H5-Re56亚型、H5-Re57亚型、H7亚型))、口蹄疫、猪瘟和小反刍兽疫等4种重大动物疫病的免疫抗体水平进行了集中检测.结果表明,4种强制免疫动物疫病的平均抗体合格率在82％～98.33％,均达到了国家规定的不低于70％的标准,整体免疫效果良好,但病种之间、各县(市)之间、场点类型之间和动物种类之间,免疫抗体水平存在一定差异.

近年来,凉山州加大了县级兽医实验室建设力度,实验室在设施设备、人员队伍、质量管理等方面都有显著提高.本文通过分析当前凉山州县级兽医实验室运行现状,提出对策,为县级兽医实验室进一步建设和发展提供思路. 1实验室运行情况 1.1检测情况 近年来,凉山州有15个县(市)兽医实验室能正常开展实验室检测工作,总体来看,全州实验室检测量逐年增加,但依然不能满足当前全州动物疫病监测预警的需要,另一方面,县(市)之间的检测量差异很大,有的县(市)年度检测量超过1万份次,而有些县年度检测量不足100份次.

为了解我国西南地区猪繁殖与呼吸综合征病毒(PRRSV)流行株的遗传变异和分子流行病学情况.本研究采集2018年我国四川、重庆、贵州和云南4省共计41个猪场292份疑似PRRS患病保育猪病料样本(肺脏样本48份和血清样本244份),对其进行PRRSV ORF7基因的检测和流行株全基因组特征分析.结果 显示PRRSV的检出率为44.18％(95％confidence interval (CI)=38.4 ％～50.1％,129/292).通过RT-PCR检测129份阳性样本的NSP2基因,结果有64份样品检出该基因.经测序分析表明类NADC30病毒株、高致病性病毒株(HP-PRRSV)和经典株的检出率分别为70.3％(95％CI=57.6％～81.1％,45/64)、12.5％(95％CI=5.6％～23.2％,8/64)和17.2％(95％CI=8.9 ％～28.7％,11/64).通过对7株病毒基因组同源性分析结果表明其均与类NADC30病毒株SD53-1603同源性最高,为95.6 ％～96.4％,与欧洲型病毒株LV同源性最低,为58.7％～59.5％;通过对7株PRRSV基因组进行遗传演化分析结果显示其均与类NADC30病毒株聚为一大支;重组分析结果显示其均未与任何病毒株发生基因重组.序列分析显示7株病毒株均在GP5蛋白发生了一个氨基酸(S/N33)的缺失,并且存在该缺失模式的病毒已经在我国其它地区存在和流行.本研究表明近年来我国西南地区类NADC30病毒株的感染率呈逐年上升趋势,并且已经成为西南地区PRRSV的优势流行株.提示规模化养殖场应更加注重生物安全,完善引种程序,避免引入新的类NADC30病毒株.

This study was performed to investigate the prevalence and genetic variation of hepatitis E virus (HEV) in Tibetan pigs and to determine its ability to infect mice. A total of 38 out of 229 (16.59%; 95% CI = 12.00%–22.10%) fecal samples from Tibetan pigs from the Qinghai-Tibetan Plateau in 2018 were positive for HEV RNA, which was detected by RT-nPCR. Significantly different detection rates were observed between samples from diarrheic and clinically healthy animals (OR = 9.56; 95% CI, 2.84–32.14; p < 0.001), suggesting a potential association between HEV infection and diarrhea in Tibetan pigs. Phylogenetic analysis showed that the HEV isolates were clustered into subtypes 4a (31 samples), 4b (1), 4d (2), and 4j (4). HEV-4a was the predominant subtype, indicating that it might be circulating in Tibetan pigs. Nine complete HEV genome sequences obtained from Tibetan pigs were found by phylogenetic analysis to be closely related to those of genotype 4 HEV isolates from humans. Two recombinant events were identified in both HEV-4a strains; a novel recombination breakpoint was first identified at the 3’ end of the ORF2 region in the SWU/L9/2018 strain, and a common recombination region was found at the junction of the ORF1 and ORF2 regions in the SWU/31-12/2018 strain. Furthermore, HEV-4a could be detected in all BALB/c mice that were experimentally infected by gavage and contact exposure. The information presented here about the prevalence and genotype diversity of HEV from Tibetan pigs provides important insights into the epidemic features of HEV on the Qinghai-Tibetan Plateau.

2017年8月四川省某规模化猪场出现临产母猪产弱子、发抖、死胎,且死胎率达30％,哺乳仔猪成活率明显降低,其中以全身性或局部性阵发痉挛为典型症状.用RT-PCR扩增及序列分析确诊该猪场感染了一种新型的猪非典型瘟病毒(APPV).这是四川省首次检测到并报道APPV,可为该病的研究和防控提供了一定的参考.

Porcine respiratory disease complex (PRDC), a common piglet disease, causes substantive economic losses in pig farming. To investigate the viral diversity associated with PRDC, the viral communities in serum and nasal swabs from 26 PRDC-affected piglets were investigated using metagenomics. By deep sequencing and de novo assembly, 17 viruses were identified in two pooled libraries (16 viruses from serum, nine from nasal swabs). Porcine circovirus (PCV)-2, porcine reproductive and respiratory syndrome virus (PRRSV) and pseudorabies virus, all commonly associated with PRDC, were identified in the two pooled samples by metagenomics, but most viruses comprised small linear and circular DNAs (e.g. parvoviruses, bocaviruses and circoviruses). PCR was used to compare the detection rates of each virus in the serum samples from 36 PRDC-affected piglets versus 38 location-matched clinically healthy controls. The average virus category per sample was 6.81 for the PRDC-affected piglets and 4.09 for the controls. Single or co-infections with PCV-2 or PRRSV had very high detection rates in the PRDC-affected piglets. Interestingly, porcine parvovirus (PPV)-2, PPV-3, PPV-6 and torque teno sus virus 1a were significantly associated with PRDC. These results illustrate the complexity of viral communities in the PRDC-affected piglets and highlight the candidate viruses associated with it.

Atypical porcine pestivirus (APPV) causes congenital tremor (CT) in piglets and has a wide geographical distribution. In this study, we evaluated APPV prevalence using 165 piglet sera from southwest China. Viral RNA was detectable by qRT-PCR in 43.6 % (17/39, 95 % CI 27.8-60.4 %) of piglets with CT, while viral RNA was not detected in the sera of any healthy piglets. The seven complete APPV genomes were obtained from distinct farms and were 11 269-11 459 nucleotides in length. The genomes of the seven strains shared 82.8-98 % identity with the APPV reference strains. Phylogenetic analysis of the complete genomes as well as E2 and Nrpo sequences revealed that the seven APPVs clustered into two groups: four strains belonged to genogroups A and D and three strains belonged to a novel APPV genotype, tentatively called genogroup E. This study provides important insights into the epidemiological features and genetic diversity of APPV.