This experiment aimed to investigate the effects of in ovo amniotic cavity injection with Lactobacillus salivarius XP132 on the immune function and intestinal microbiota of layer chicks. A total of 150 SPF laying chicken eggs were selected and randomly divided into two groups, with three replicates per group and 25 eggs per replicate. Group DZ was injected with 0.2 mL of sterile physiological saline into the amniotic cavity at 18 days of embryonation. Group MY was injected with 0.2 mL of a Lactobacillus salivarius XP132 suspension containing 1.21×108 CFU/mL via the amniotic cavity at 18 days of embryonation. The incubation period was 21 days, and the feeding period was 35 days. The results showed that compared to group DZ, serum level of interleukin-2 (IL-2) in the group MY was significantly increased at 14, 21, and 28 days of age (P<0.05), and significantly increased the levels of interleukin-4 (IL-4), interleukin-6 (IL-6), and interferon-γ (IFN-γ) at 7, 14, and 21 days of age (P<0.05). The number of immunoglobulin A-positive cells (IgA+ cells) in the duodenum and ileum at 21 and 35 days of age was significantly increased in group MY (P<0.05), and the number of IgA+ cells in the jejunum at 7 and 21 days of age was significantly increased (P<0.05). At 7 and 21 days of age, the Shannon index and Chao1 index in group MY were significantly higher than in the group DZ (P<0.05), and the Simpson index was significantly lower than in the group DZ (P<0.05). At 7 days of age, the relative abundances of Lactobacillus and Oscillospira in group MY were higher than in the group DZ, while the relative abundance of Shigella was lower than in the group DZ. At 21 days of age, the relative abundance of Lactobacillus in group MY was higher than in the group DZ, and the relative abundance of Shigella was lower than in the group DZ. At 35 days of age, the relative abundance of Shigella in group MY was lower than in the group DZ. The study shows that in ovo amniotic injection of Lactobacillus salivarius XP132 can enhance the immune function and improve the diversity of cecal microbiota of layer chicks.

The intestine serves as a vital immune barrier organ in poultry. During the growth and development of poultry, diverse microorganisms colonize the gut and form complex communities. These microorganisms include both potential pathogens such as Escherichia coli and Salmonella, and beneficial bacteria such as Lactobacilli. Different microbial communities constrain each other, collectively maintaining a relatively stable intestinal microecology. This microecology plays a crucial role in preserving intestinal barrier integrity, regulating immune function, and resisting pathogen invasion. A deeper understanding of the colonization and succession patterns of intestinal microorganisms in poultry will aid in developing more targeted microecology regulation strategies. This article reviews the research progress on intestinal microbial colonization, microorganisms balance and dysbiosis, and their physiological functions, aiming to provide references for subsequent research on regulating poultry intestinal microorganisms, as well as for improving poultry intestinal microecology, enhancing intestinal mucosal immunity, and advancing healthy farming practices.

Avibacterium paragallinarum (Av. Paragallinarum) infection causes infectious coryza, which is a widespread and serious respiratory disease in chickens. Although the HutZ protein has been linked to heme utilization and virulence in various pathogens, a specific role in host-pathogen interactions during Av. paragallinarum infection remains unclear. In this study, to investigate host immune responses and the regulatory role of HutZ following Av. paragallinarum infection, we performed the transcriptomic profiles of avian macrophage HD11 following wild and HutZ mutant of Av. paragallinarum infection using RNA-seq, respectively. The differentially expressed genes (DEGs) in the HD11 macrophages between the two groups were identified. Compared with the uninfected group, more DEGs involved in signaling pathways and cellular functions were identified in the infected groups. Our results revealed extensive transcriptional changes following infection, with both bacterial strains activating core immune pathways including PI3K-Akt and MAPK signaling. Notably, the HutZ mutant elicited stronger activation of pattern recognition receptor pathways such as Toll-like, NOD-like, and RIG-I-like signaling, suggesting that HutZ may help the pathogen evade host immune detection. This work provides novel insights into the immunomodulatory role of HutZ and offers a foundation for developing targeted interventions against Av. paragallinarum.

H9N2 influenza virus, a prevalent influenza A virus, causes acute lung injury through mitochondrial damage associated with oxidative stress. Transient receptor potential melastatin 2 (TRPM2) is a Ca2+ permeable non-selective cation channel that can trigger oxidative stress via Ca2+ overload. Excessive ROS generation leads to mitochondrial dysfunction and lipid peroxides accumulation, contributing to ferroptosis. However, it remains unclear whether H9N2 virus infection can trigger ferroptosis in mouse lungs and its relationship with TRPM2. Therefore, this study investigates the protective effect of TRPM2 knockdown against lung injury infected by H9N2 virus and explores its potential molecular mechanisms, with a particular focus on its association with ferroptosis. In vitro, we infected mouse pulmonary microvascular endothelial cells (PMVECs) with H9N2 virus, or/and transfected them with siTRPM2 at 80 nM. Our findings revealed that TRPM2 knockdown significantly reduced Ca2+ overload and ROS generation, and upregulated the mRNA and protein expression levels of catalase (CAT), superoxide dismutase 1 (SOD1), and heme oxygenase-1 (HO-1). This intervention also alleviated mitochondrial damage and maintained mitochondrial dynamics balance. H9N2 virus infection disrupted the Glutathione/Glutathione oxidized (GSH/GSSG) system and increased lipid peroxidation-related factors (Lysophosphatidylcholine acyltransferase 3 [LPCAT3] and Acyl-CoA synthetase long chain family member 4 [ACSL4]), which were mitigated by TRPM2 knockdown. Additionally, TRPM2 ablation reduced Fe2+ intensity and the expression levels of iron metabolism-related factors (Transferrin [TF] and Transferrin receptor [TFR]). In conclusion, TRPM2 knockdown inhibited H9N2 virus-induced ferroptosis by mitigating Ca2+ overload, oxidative stress, mitochondrial dysfunction, GSH/GSSG system imbalance, lipid peroxidation, and iron metabolism imbalance.

This study delves into the antiviral efficacy of Formononetin (FMN) and Mizoribine (MZR) against the Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), a virus with a considerable economic impact and a current void in effective treatments. FMN and MZR were found to inhibit various PRRSV strains in vitro, predominantly in the early stages of viral infection. Noteworthy was the observation of their synergistic effects when combined with Ribavirin. The study underscores the antiviral potential of FMN and MZR, particularly emphasizing their low cytotoxicity at specific concentrations. These results position FMN and MZR as promising antiviral agents against PRRSV, underscoring their low cytotoxicity and efficacy in early-stage viral inhibition. Such findings pave the way for their potential inclusion in future PRRSV management strategies.

Oxidative stress is involved in lung damage induced by the influenza virus. The transient receptor potential melastatin-2 (TRPM2) cation channel, a Ca2+ permeable non-selective cation channel, is implicated in the mediation of multiple tissue injuries induced by oxidative stress. The role of TRPM2 in several diseases has been widely studied, but there have been few studies on the involvement of TRPM2 in lung injury induced by the H9N2 influenza virus. We investigated the effects of TRPM2 on pathological alterations, oxidative stress, apoptosis, and inflammation in mice infected with H9N2 virus. TRPM2 knockout (TRPM2-/-) mice and wild-type (WT) mice were infected separately with H9N2 influenza virus. Pulmonary oedema, lung permeability, Ca2+ concentration, redox imbalance, apoptosis, and levels of inflammatory factors (IL-1β, IL-6, TNF-α) were increased in WT mice infected with H9N2 virus. However, these effects were diminished by TRPM2 knockout. Our results emphasised the significance of TRPM2 knockdown in mitigating pathological lung alterations, maintaining Ca2+ homeostasis, reducing oxidative damage, preventing apoptosis, and suppressing the production of inflammatory cytokines in H9N2 virus-infected mice. Therefore, inhibition of TRPM2 activation is a potentially important therapeutic strategy for treating lung injury.

Download This Paper Open PDF in Browser Add Paper to My Library Share: Permalink Using these links will ensure access to this page indefinitely Copy URL Copy DOI

禽致病性大肠杆菌病(Avian Pathogenic Es-cherichia Colibacillosis,APEC)主要引起家禽的急性或慢性感染,表现为急性败血症、肝周炎、心包炎、脐炎、气囊炎等.由于大肠杆菌在外界环境广泛存在,因此临床上常引起原发性感染或继发于其他病原感染,如H9N2亚型禽流感病毒等.目前大肠杆菌血清型较多,加之在不同区域能够引起禽类感染的APEC血清型不同等因素给大肠杆菌的免疫防控带来了困难,因此在临床上APEC的防控主要采用抗生素为主.

鸡呼吸道疾病综合征是由传染性因素(病毒、细菌、支原体等病原体)和非传染性因素(环境、饲养管理等)多种致病因子共同作用而引起的并发或混合感染的呼吸道疾病.此病秋冬季节多发,鸡群具有发病率高、传播速度快且死亡率低等特点.临床上主要表现为咳嗽、喷嚏、啰音等呼吸道症状,同时伴有结膜炎、角膜炎、面部肿胀等病理改变,并造成生长速度和生产性能的降低,对我国养禽业造成巨大经济损失.该文从鸡的呼吸系统解剖生理结构特点,鸡呼吸系统综合征发病的病因和诱因,并有针对性地提出了科学的防制方案.

At the end of embryonic development of poultry, the vigorous metabolic activity of embryo increases the risk of insufficient nutrient supply in hatching process, which cannot fully meet the needs of rapid development after shell, and is easy to cause irreversible damage to later growth and production of poultry. Providing exogenous nutrients to embryos during the incubation period can promote the growth and development of chicks in later stage of incubation and after emerging from shell, improve the quality of poultry seedlings, to achieve the effect of promoting their production performance and maintaining intestinal health, and advance the early nutritional regulation of poultry after emerging from shell to the later stage of incubation. As a new ultra early nutrition control technology, embryo egg inoculation can provide a new idea for the growth and development of poultry. The paper reviews the research on early nutrition regulation of poultry by embryo egg inoculation in recent years from the aspects of embryo egg inoculation methods, the effect of the nutrients of embryo egg inoculation on the growth and development of poultry and intestinal health, so as to provide reference for the research of embryo stage inoculation of poultry.

为建立H9N2亚型禽流感病毒(AIV)抗体快速、高效的血清学检测方法,参考GenBank数据库中H9N2 AIV的HA基因序列(登录号:MK995886.1)设计并合成特异性引物,以H9N2 AIV RNA为模板,RT-PCR扩增目的基因HA1,构建pET28a-HA1重组质粒,经原核系统表达获得HA1蛋白.通过SDS-PAGE和Western-blot鉴定蛋白表达和反应原性,用纯化后的HA1重组蛋白作为包被抗原建立间接ELISA方法.结果显示,该检测方法抗原最佳包被浓度为0.2 μg/mL,血清最佳稀释度为1:160,用1％BSA溶液37 ℃封闭60 min效果最佳,酶标二抗最佳稀释度为1∶6 000,具有较高的特异性、灵敏性和符合率.上述结果表明,本试验成功表达并纯化了 H9N2AIV的HA1蛋白,建立的间接ELISA检测方法为H9N2 AIV的流行病学调查、免疫效果评价及临床诊断试剂盒的开发奠定了基础.

H9N2 virus is mainly transmitted through the respiratory mucosal pathway, so mucosal immunity is considered to play a good role in controlling avian influenza infection. It is commonly accepted that no adequate mucosal immunity is achieved by inactivated vaccines, which was widely used to prevent and control avian influenza virus infection. Thus, an improved vaccine to induce both mucosal immunity and systemic immunity is urgently required to control H9N2 avian influenza outbreaks in poultry farms. In this study, we constructed a novel Lactococcus lactis (L. lactis) strain expressing a recombinant fusion protein consisting of the HA1 proteins derived from an endemic H9N2 virus strain and chicken IgY Fc fragment. We evaluated the immunogenicity and protective efficacy of this recombinant L. lactis HA1-Fc strain. Our data demonstrated that chickens immunized with L. lactis HA1-Fc strain showed significantly increased levels of serum antibodies, mucosal secretory IgA, T cell-mediated immune responses, and lymphocyte proliferation. Furthermore, following challenge with H9N2 avian influenza virus, chickens immunized with L. lactis HA1-Fc strain showed reduced the weight loss, relieved clinical symptoms, and decreased the viral titers and the pathological damage in the lung. Moreover, oropharyngeal and cloacal shedding of the H9N2 influenza virus was detected in chicken immunized with L. lactis HA1-Fc after infection, the results showed the titer was low and reduced quickly to reach undetectable levels at 7 days after infection. Our data showed that the recombinant L. lactis HA1-Fc strain could induce protective mucosal and systemic immunity, and this study provides a theoretical basis for improving immune responses to prevent and control H9N2 virus infection.

抗菌肽(AMPs)在动物、植物内广泛存在.抗菌肽是机体细胞特殊基因由转录、翻译等过程产生的一类由12～50个氨基酸组成的小肽物质,是机体固有免疫重要组成部分,构成了机体防御病原微生物的第一道防线.抗菌肽具有分布范围广、广谱抗菌活性强、不易产生耐药性、热稳定性高、抗病毒等作用.抗菌肽作为饲料添加剂广泛应用于家禽防治疾病、增强免疫、改善肠道菌群以及提高禽类生长性能等方面.文章主要从抗菌肽的种类及其抗细菌作用、抗病毒作用、防治疾病、改善肠道菌群以及提高禽类生长性能等方面进行阐述,为后期抗菌肽的研究与应用提供参考.

利用CRISPR/Cas9 技术构建瞬时受体电位M2(TRPM2)基因敲除的杂合子小鼠模型.参考Ensembl数据库中Trpm2-203 的内含子 2 和内含子 24 序列选择sgRNA靶点并进行体外合成.通过体外转录方式获得Cas9 mR-NA,将其与sgRNA显微注射至C57BL/6J小鼠的受精卵后,移植到假孕母鼠的输卵管内,获得F0 代小鼠.阳性F0代小鼠分别与野生型C57BL/6J小鼠交配获得F1 代.结果显示,经PCR产物测序共获得 3 只阳性F0 代小鼠;阳性F0 代小鼠分别与野生型C57BL/6J小鼠交配获得 4 个品系,共获得 27 只阳性F1 代小鼠.通过实时荧光定量PCR和Western Blot方法验证,表明研究成功构建TRPM2 基因敲除杂合子小鼠(TRPM2+/-),为下一步开展TRPM2 基因及其表达产物的生物功能研究提供良好的动物模型.

副猪嗜血杆菌病是一种由副猪嗜血杆菌引起猪的接触性传染病,又称纤维性浆膜炎和关节炎.副猪嗜血杆菌病的发病率每年呈明显的上升趋势,对猪场造成严重的经济损失.本文介绍了一例保育猪副猪嗜血杆菌病的发病情况、临床剖检、实验室诊断、治疗与防控,以期为副猪嗜血杆菌病的临床诊断与防治提供参考.

本试验旨在研究H9N2流感病毒感染MDCK细胞引发的细胞自噬对病毒复制的影响.试验首先建立了稳定表达GFP-LC3的MDCK细胞系,该细胞系经H9N2流感病毒感染后,激光共聚焦观察到了绿色荧光的点状聚集,得出H9N2流感病毒感染MDCK细胞引发细胞自噬.随后试验利用3-MA抑制细胞自噬、Rapamycin诱导细胞自噬,荧光定量PCR检测NP mRNA水平,TCID50检测病毒的滴度进行细胞自噬与病毒复制的研究.结果表明:Rapamycin可显著增加NP mRNA水平和病毒滴度(P<0.01);3-MA可以显著降低NP mRNA水平和病毒滴度(P<0.01).说明H9N2流感病毒感染MDCK细胞引发的细胞自噬可促进流感病毒的复制.

猪繁殖与呼吸综合征,俗称"蓝耳病",是由繁殖呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PPRSV)引起猪的一种具有高度接触性和高死亡率的传染性疾病.典型的临床症状为断奶前后的仔猪会出现呼吸系统疾病以及妊娠后期母猪繁殖障碍,该病自1987年首次报道以来,尤其是2006年变异性高致病性PPRSV的出现,给我国生猪养殖行业带来了巨大的经济损失.尽管非洲猪瘟在我国的发生对生猪养殖业导致严重经济损失,但是在常态化非洲猪瘟防控下如何做好以繁殖呼吸综合征等重要疾病对于提高生猪养殖业提质增效仍具有重要意义.现将PPRS的现状以及防控措施综述如下.

试验旨在研究葡萄糖氧化酶(GOD)和乳酸菌制剂联合应用对肉鸡肠道形态及微生物菌群的影响.选取1日龄AA肉鸡1200只,随机分为4组,Ⅰ组为对照组,正常饮水;Ⅱ组为GOD组,在饮水中添加0.1％ GOD;Ⅲ组为乳酸菌制剂组,在每只鸡饮水中添加1.5×105 CFU/(g·d)乳酸菌制剂;Ⅳ组为GOD与乳酸菌制剂联合应用组,添加剂量同Ⅱ组和Ⅲ组.试验期42 d.结果 显示,试验第21 d,与对照组相比,各试验组肉鸡十二指肠绒毛高度均显著提高(P＜0.05),绒毛高度/隐窝深度(V/C)显著提高(P＜0.05);各试验组肉鸡空肠绒毛高度均显著提高(P＜0.05);试验Ⅳ组肉鸡的空肠V/C显著高于对照组(P＜0.05);各组间的隐窝深度均无显著差异(P＞0.05).试验第42 d,与对照组相比,试验Ⅱ组和试验Ⅳ组肉鸡十二指肠绒毛高度显著提高(P＜0.05),试验Ⅳ组V/C显著增加(P＜0.05).与对照组相比,各试验组Shannon指数均高于对照组(P＞0.05),Simpson指数均低于对照组(P＞0.05);与对照组相比,试验Ⅱ组Bacteroidetes的含量极显著提高(P＜0.01),试验Ⅳ组Bacteroidetes含量显著提高(P＜0.05),Bacteroidetes的含量显著降低(P＜0.05).试验Ⅱ组狄氏副拟杆菌(Parabacteroides)和长栖粪杆菌(Faecalibacterium)比例显著高于其他3组(P＜0.05).研究表明,饮水中联合添加GOD和乳酸菌制剂可改善肉鸡的肠道形态和微生物菌群结构.

本研究旨在了解TLR4信号转导在铜绿假单胞菌感染所致急性肺损伤的发病机理中的作用.通过使用Tlr4基因突变致正常TLR4信号转导缺失的C3H/HeJ小鼠,评估TLR4信号转导在调节铜绿假单胞菌引起的急性肺损伤中的作用.选用6～8周龄、雄性、TLR4缺陷型(C3H/HeJ)和SPF级野生型(C3H/HeN)的小鼠各21只,随机分为4组:C3H/HeN对照组、C3H/HeJ对照组、C3H/HeN感染组和C3H/HeJ感染组.将两个感染组的小鼠滴鼻感染致死剂量的铜绿假单胞菌.评估各组小鼠的存活率、临床症状,肺病变程度、肺细菌载量以及肺部细胞因子含量的动态变化.结果表明:1)与野生型C3H/HeN感染组小鼠相比,TLR4缺陷型C3H/HeJ感染组小鼠临床症状明显加重.其中,TLR4缺陷型C3H/HeJ感染组小鼠中位生存期更短;感染后8 h,C3H/HeJ感染组小鼠体温极显著低于C3H/HeN感染组(P＜0.01),肺组织大体病变更严重,肺水肿程度显著高于C3H/HeN感染组(P＜0.05);2)感染后8 h,TLR4缺陷型C3H/HeJ感染组小鼠肺匀浆中TNF-α和IL-1β含量极显著低于野生型C3H/HeN感染组小鼠(P＜0.01);3)TLR4缺陷型C3H/HeJ感染组小鼠肺细菌载量显著高于野生型C3H/HeN感染组(P＜0.05).综上,TLR4蛋白缺失显著增加了铜绿假单胞菌对小鼠的致病性.

近年来,随着生猪养殖规模的不断扩大,为人们带来了理想的收益.但在生猪养殖业发展中,也存在诸多的问题,目前疾病防控是许多养猪业企业面临的迫切问题.一方面,大多数猪病表现为病原体多重感染和继发感染,并且由于各种药物的滥用,出现了许多新型的动物疾病,给养殖户造成巨大损失;另一方面,许多猪病的疫苗和特效药物都处于研发状态,有些疫病虽有药可治,但是治疗效果却不是很理想[1].因此,规模化猪场对疾病的防控应坚持"预防为主,综合防治"的原则,建立猪病防控常态化机制,制定有针对性的用药策略,阻止疫情的蔓延与扩散.本文就规模化猪场防治用药的方式及注意事项进行论述.