Ameziane Samia, Salhi Omar, Hammami Nabila, Zaidi Salim, Amraoui Amina, Bensalem Aya, Tahraoui Meriem, Ouchene Nassim, Khelifi Touhami Nadjet Amina, Hireche Sana, Agabou Amir
PADESCA Research Laboratory, Institute of Veterinary Sciences El-Khroub, University of Constantine, Algeria.
Institute of Veterinary Sciences, University Saad Dahlab of Blida 1, BP 270, Blida 09000, Algeria; Laboratory of Biotechnology and Valorization of Biological Resources, Faculty of Science, University of Medea, Algeria.
Comp Immunol Microbiol Infect Dis. 2025 Jun;120:102358. doi: 10.1016/j.cimid.2025.102358. Epub 2025 May 11.
Marek's disease (MD) is a highly contagious viral infection in poultry, caused by Gallid alphaherpesvirus 2 (GaHV-2), better known as serotype 1 of Marek's disease virus (MDV-1). It is one of the most concerning diseases in the poultry industry due to its significant economic impact. The disease mainly affects chickens, although other avian species can also be affected. The objective of this study was to examine the occurrence of Marek's disease virus (MDV) in fourteen poultry farms in Algeria through autopsy, histopathological analysis and molecular characterization of Marek's disease virus. This study represents one of the first investigations combining macroscopic, histopathological, and molecular analyses to assess the prevalence and genetic diversity of Marek's disease virus in Algerian poultry farms. A survey to assess the current occurrence of Marek's disease in poultry farms in Algeria was conducted from June to December 2024. Tissue samples were collected from 70 chickens, including 35 from broiler breeder farms and 35 from layer farms. Macroscopic and histopathological examinations were performed. Macroscopic pathological alterations, such as hepatomegaly, splenomegaly, renal hypertrophy, and sciatic nerve enlargement with follicular atresia and lymphomatous infiltration, were observed. Histopathological analyses revealed diffuse and multifocal whitish infiltration of the spleen, neoplastic infiltration of the liver, intrafollicular lymphoid infiltration in the bursa of Fabricius, and infiltration in the sciatic nerves. The molecular characterization of MDV through PCR amplification and sequencing of the meq gene provides novel insights into the circulating strains in Algeria. The samples were screened by PCR amplification of the meq gene. Additionally, we sequenced the meq gene from five samples per flock, and a phylogenetic tree was constructed using the deduced amino acid sequences of the meq gene. This study is the first to identify and classify MDV strains in Algerian broiler breeder and laying hen farms, revealing the presence of very virulent (vv) MDV pathotypes. Marek's disease remains a major veterinary and economic challenge in the poultry industry, requiring ongoing research to better understand its mechanisms, genetic variations, and control methods.
马立克氏病（MD）是家禽中一种高度传染性的病毒感染，由鸡α疱疹病毒2型（GaHV - 2）引起，该病毒更广为人知的名称是马立克氏病病毒1型（MDV - 1）。由于其重大的经济影响，它是家禽业最令人担忧的疾病之一。这种疾病主要影响鸡，不过其他禽类也可能受到影响。本研究的目的是通过对马立克氏病病毒进行尸检、组织病理学分析和分子特征鉴定，来检测阿尔及利亚14个家禽养殖场中马立克氏病病毒（MDV）的发生情况。本研究是首批结合宏观、组织病理学和分子分析来评估阿尔及利亚家禽养殖场中马立克氏病病毒的流行情况和遗传多样性的调查之一。2024年6月至12月对阿尔及利亚家禽养殖场中马立克氏病的当前发生情况进行了一项调查。从70只鸡身上采集了组织样本，其中35只来自肉种鸡场，35只来自蛋鸡场。进行了宏观和组织病理学检查。观察到了宏观病理改变，如肝肿大、脾肿大、肾肥大以及伴有卵泡闭锁和淋巴瘤浸润的坐骨神经增粗。组织病理学分析显示脾脏有弥漫性和多灶性白色浸润、肝脏有肿瘤浸润、法氏囊内有滤泡内淋巴浸润以及坐骨神经有浸润。通过对meq基因进行PCR扩增和测序对MDV进行分子特征鉴定，为阿尔及利亚流行毒株提供了新的见解。通过对meq基因进行PCR扩增对样本进行筛选。此外，我们对每个鸡群的5个样本的meq基因进行了测序，并使用meq基因推导的氨基酸序列构建了系统发育树。本研究首次在阿尔及利亚肉种鸡和蛋鸡养殖场中鉴定并分类了MDV毒株，揭示了超强毒（vv）MDV致病型毒株的存在。马立克氏病仍然是家禽业的一个主要兽医和经济挑战，需要持续开展研究以更好地了解其发病机制、遗传变异和控制方法。
