This work aims to: (1) elucidate the immune response exhibited by CD4+ and CD8+ T lymphocyte cells in response to various infectious agents in calves suffering with neonatal diarrhea; and (2) determine and investigate the association between serum selenium levels and T lymphocyte subtypes in neonatal calves afflicted with neonatal diarrhea and infected with various infectious agents. The study encompassed a cohort of 50 calves, encompassing both sexes and various breeds, within the neonatal age range (1-28 days old). Subdivided into distinct groups, the calves were categorized based on the causative agents of neonatal diarrhea, including Rotavirus (n=10), Cryptosporidium parvum (C.parvum) (n=10), Coronavirus (n=5), Rotavirus+C.parvum (n=5), and a Control group (n=20). Blood samples were meticulously obtained from the vena jugularis of all animals utilizing specific techniques—8ml in tubes devoid of anticoagulant and 3ml in blood collection tubes containing EDTA. Serum selenium levels were analyzed by ICP-MS. Flow Cytometry device was used to determine CD4+ and CD8+T lymphocyte levels.

中文翻译：

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新生儿腹泻犊牛外周循环淋巴细胞的免疫表型和血清硒水平

本工作的目的是：(1) 阐明患有新生儿腹泻的犊牛中 CD4+ 和 CD8+ T 淋巴细胞对各种感染因子所表现出的免疫反应；(2)确定并研究患有新生儿腹泻和感染各种传染原的新生犊牛血清硒水平与T淋巴细胞亚型之间的关联。该研究涵盖了 50 头犊牛，包括不同性别和不同品种的新生年龄范围（1-28 天）。根据新生儿腹泻的病原体将犊牛分为不同的组，包括轮状病毒（n=10）、小隐孢子虫（C.parvum）（n=10）、冠状病毒（n=5）、轮状病毒+C。 parvum (n=5) 和对照组 (n=20)。利用特定技术从所有动物的颈静脉中精心采集血样——8ml 在不含抗凝剂的试管中，3ml 在含有 EDTA 的采血管中。通过 ICP-MS 分析血清硒水平。使用流式细胞术装置测定CD4+和CD8+T淋巴细胞水平。