Yadav Pradeep Kumar, Shah Showkat Ahmad, Shafi Majid, Kamil Shayaib Ahmad, Mir Masood Saleem, Rather Mudasir Ali, Ganaie Ajaz Ahmad, Wani Zahoor Ahmad
Veterinary Pathology, Faculty of Veterinary Sciences and Animal Husbandry, SKUAST-K, Srinagar, India.
Associate Director Research, Directorate of Research, SKUAST-K, Srinagar, India.
Open Vet J. 2024 Nov;14(11):3037-3046. doi: 10.5455/OVJ.2024.v14.i11.32. Epub 2024 Nov 30.
Early chick mortality (ECM) is one of the most important problems of the poultry industry that causes severe economic losses to the farmers. The chick mortality varies in different geographical locations and its etiological factor also varies.
The aim of the present work was to isolate and identify various etiological agents responsible for causing ECM in broilers, and study the overall occurrence and pathology of various disease conditions responsible for causing ECM in broilers.
The study included clinical and laboratory investigations vis-a-vis ECM. A total of 2,346 broiler chickens under the age group of 2 weeks from around 87 outbreaks were necropsied and examined for the presence of lesions corresponding to different disease conditions. Representative samples (heart, liver, intestine, lung, and spleen) were collected in a sterile Petri dish for bacterial and fungal isolation and stored at 4°C till inoculation in nutrient broth, followed by a collection of tissue samples (heart, liver, lung, spleen, intestines, and kidney) in 10% buffered formalin for histopathological examination.
The overall mortality in the flocks was 1.7%, with 1.6% mortality in the first week and 1.8% in the second week of life. Colibacillosis was responsible for causing the highest ECM of 2.01% followed by salmonellosis (1.9%), aspergillosis (0.9%), and gout (0.6%). The case prevalence of colibacillosis, salmonellosis, aspergillosis, and gout was seen as 58.1%, 32.3%, 6.4%, and 3.2%, respectively. Colibacillosis (2.1%), salmonellosis (3.2%), and gout (1.7%) were responsible for causing higher mortality (3.2%) in the second week of life of broilers, aspergillosis in the first week (1.0%) and gout caused similar percentage of mortalities in the first and second week of life. Microscopic changes were predominately characterized by congestion, hemorrhage, infiltration by various inflammatory cells especially heterophils, the focal granulomatous reaction in aspergillosis, and urates in the tubular parenchyma in the form of pink amorphous radiating material surrounded by a narrow zone of inflammatory cells in cases of visceral gout.
Salmonellosis, colibacillosis, aspergillosis, and gout were diseases mainly responsible for ECM in broilers. Colibacillosis was responsible for causing the highest ECM followed by aspergillosis, salmonellosis, and gout.
雏鸡早期死亡率（ECM）是家禽业最重要的问题之一，给养殖户造成了严重的经济损失。雏鸡死亡率在不同地理位置有所不同，其病因也各不相同。
本研究的目的是分离和鉴定导致肉鸡ECM的各种病原体，并研究导致肉鸡ECM的各种疾病状况的总体发生率和病理学。
该研究包括针对ECM的临床和实验室调查。对来自约87起疫情的2346只2周龄以下的肉鸡进行了尸检，并检查是否存在与不同疾病状况相对应的病变。在无菌培养皿中收集代表性样本（心脏、肝脏、肠道、肺和脾脏）用于细菌和真菌分离，并在4°C下保存直至接种到营养肉汤中，随后收集组织样本（心脏、肝脏、肺、脾脏、肠道和肾脏）置于10%缓冲福尔马林中进行组织病理学检查。
鸡群的总体死亡率为1.7%，出生第一周死亡率为1.6%，第二周为1.8%。大肠杆菌病导致的ECM最高，为2.01%，其次是沙门氏菌病（1.9%）、曲霉菌病（0.9%）和痛风（0.6%）。大肠杆菌病、沙门氏菌病、曲霉菌病和痛风的病例发生率分别为58.1%、32.3%、6.4%和3.2%。大肠杆菌病（2.1%）、沙门氏菌病（3.2%）和痛风（1.7%）导致肉鸡出生第二周死亡率较高（3.2%），曲霉菌病导致第一周死亡率较高（1.0%），痛风在肉鸡出生第一周和第二周导致的死亡率相似。微观变化主要表现为充血、出血、各种炎症细胞尤其是嗜异性粒细胞浸润、曲霉菌病中的局灶性肉芽肿反应，以及内脏痛风病例中肾小管实质内呈粉红色无定形放射状物质且被狭窄炎症细胞带包围的尿酸盐。
沙门氏菌病、大肠杆菌病、曲霉菌病和痛风是导致肉鸡ECM的主要疾病。大肠杆菌病导致的ECM最高，其次是曲霉菌病、沙门氏菌病和痛风。
