Effects of Salmonella enterica serovar Enteritidis infection on egg production and the immune response of the laying duck Anas platyrhynchos
Effects of Salmonella enterica serovar Enteritidis infection on egg production and the immune response of the laying duck Anas platyrhynchos
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肠炎沙门氏菌感染对鸭鸭产蛋量及免疫反应的影响
DOI：
10.7717/peerj.6359
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发表时间：
2019-01-25
期刊：
影响因子：
2.7
通讯作者：
Chen, Guohong
中科院分区：
文献类型：
--
作者：
Zhang, Yu;Chen, Yang;Chen, Guohong
肠炎沙门氏菌（SE）在禽类生殖道中持续定植，会对产蛋量产生负面影响并污染鸡蛋。卵巢和输卵管的免疫功能对于防止感染和产生健康的卵子至关重要。然而，蛋鸭在 SE 感染期间的免疫反应尚不清楚。在这项研究中，鸭子 (Anas platyrhynchos) 感染了 SE，并在 13 周内系统地监测其排泄物情况。我们还评估了生殖道中的细菌分布，并根据组织病变的存在以及从粪便样本中分离出的SE，将受感染的鸭子分类为耐药或易感。我们发现受感染的动物会出现持续但间歇性的细菌脱落，从而导致带菌鸭的产生。 SE感染后产蛋率和蛋品质也下降（P < 0.05）。 SE 很容易在易感鸭生殖道的基质、小卵泡、峡部和阴道中定植。与抗性鸭相比，易感鸭的免疫球蛋白（IgA、IgG、IgM）水平较高（P < 0.05）； T淋巴细胞亚群（CD3+、CD4+、CD8+）表现出相反的趋势。 qRT-PCR 分析用于检查受感染鸭生殖道中免疫反应基因的表达谱。分析显示，免疫基因，包括Toll样受体（TLR2、TLR4-5、TLR15、TLR21）、NOD样受体（NOD1、NLRX1、NLRP12）、禽β-防御素（AvβD4-5、AvβD7、AvβD12）、细胞因子（IL-6、IL-1β、IFN-γ）和MyD88显着升高。 SE 感染鸭的生殖道中表达上调（所有 P < 0.05）； TLR3、TLR7、NLRC3、NLRC5 和 TNF-α 显着下调。这些结果表明，SE 感染导致鸡蛋产量和质量降低，并改变 TLR、NLR、AvβD 和细胞因子家族基因的表达。这些发现为进一步研究蛋鸭SE感染的生理和免疫机制提供了基础。
Persistent colonization of the avian reproductive tract by Salmonella enterica serovar Enteritidis (SE) negatively affects egg production and contaminates the egg. The immune function of the ovary and oviduct is essential for protection from infection and for the production of wholesome eggs. However, the immune response of laying ducks during SE infection is not well-understood. In this study, ducks (Anas platyrhynchos) were infected with SE and were systematically monitored for fecal shedding during a 13-week period. We also assessed bacterial distribution in the reproductive tract and classified infected ducks as resistant or susceptible based on the presence of tissue lesions and on SE isolation from fecal samples. We found that infected animals had persistent, but intermittent, bacterial shedding that resulted in the induction of carrier ducks. Laying rate and egg quality were also decreased after SE infection (P < 0.05). SE readily colonized the stroma, small follicle, isthmus, and vagina in the reproductive tracts of susceptible ducks. Immunoglobulin (IgA, IgG, IgM) levels were higher in susceptible ducks compared with resistant birds (P < 0.05); T-lymphocyte subpopulations (CD3+, CD4+, CD8+) displayed the opposite trend. qRT-PCR analysis was used to examine expression profiles of immune response genes in the reproductive tract of infected ducks. The analysis revealed that immune genes, including toll-like receptors (TLR2, TLR4-5, TLR15, TLR21), NOD-like receptors (NOD1, NLRX1, NLRP12), avian β-defensins (AvβD4-5, AvβD7, AvβD12), cytokines (IL-6, IL-1β, IFN-γ), and MyD88 were markedly upregulated in the reproductive tracts of SE-infected ducks (all P < 0.05); TLR3, TLR7, NLRC3, NLRC5, and TNF-α were significantly downregulated. These results revealed that SE infection promoted lower egg production and quality, and altered the expression of TLRs, NLRs, AvβDs, and cytokine family genes. These findings provide a basis for further investigation of the physiological and immune mechanisms of SE infection in laying ducks.