Villegas Ana M, Berghaus Roy, Zavala Guillermo, Barrios Miguel A, França Monique
A Poultry Diagnostic and Research Center.
B Department of Population Health, University of Georgia, Athens, GA 30602.
Avian Dis. 2018 Jun;62(2):241-246. doi: 10.1637/11783-121617-ResNote.1.
Focal duodenal necrosis (FDN) is an intestinal disease of egg-laying chickens, characterized by multifocal mucosal erosions in the duodenal loop and proximal jejunum. It is currently considered by the Association of Veterinarians in Egg Production and the United States Animal Health Association as one of the top five disease concerns of the table egg industry in the United States. Previous studies have associated this condition with Clostridium species. The purpose of this study was to investigate the epidemiologic characteristics of table egg layer flocks affected with FDN. An online questionnaire was distributed to commercial layer operations in different states in the United States. Layer farms that had diagnosed FDN within the past 12 mo were surveyed. The questionnaire had 45 questions about management, nutrition, housing, and methods for disease prevention and control. Thirty-seven surveys were sent and 21 were completed, which represents a response rate of 56.7%. The survey results showed the presence of FDN in five egg-layer genetic lines or breed crosses of different ages, with most cases reported between 30-39 wk of age. The pullets were cage-reared in all affected flocks and the majority of flocks in production were housed in traditional cages. Most of the FDN-affected flocks received more than 12 different feed formulations from pre-lay to 60 wk of age. Distiller's dried grain with solubles was a common ingredient added to the feed in the majority of affected flocks, and all flocks were provided with limestone as a calcium source for egg production. Most surveys reported that coccidiosis and roundworm parasitism were not problems in affected flocks in production; however, pests such as flies and rodents were reported as problems in most affected flocks. Additionally, most affected farms never washed feeders, cages, and houses before disinfection, which may not be sufficient to prevent the persistency and transmission of the causative agent of FDN. In conclusion, several management practices that have been associated with enteric disease, including clostridial-associated enteritis, were described by the majority of FDN-affected flocks. Additional studies are needed to determine if management and health practices identified in this survey represent risk factors for FDN.
局灶性十二指肠坏死（FDN）是蛋鸡的一种肠道疾病，其特征为十二指肠袢和空肠近端出现多灶性黏膜糜烂。目前，蛋鸡生产兽医协会和美国动物卫生协会将其视为美国蛋鸡产业最为关注的五大疾病之一。此前的研究已将这种病症与梭菌属联系起来。本研究的目的是调查受FDN影响的蛋鸡群的流行病学特征。向美国不同州的商业蛋鸡养殖场发放了一份在线调查问卷。对在过去12个月内诊断出患有FDN的蛋鸡养殖场进行了调查。该问卷有45个关于管理、营养、鸡舍以及疾病预防和控制方法的问题。共发放了37份调查问卷，21份完成了回复，回复率为56.7%。调查结果显示，在五个不同年龄的蛋鸡遗传品系或杂交品种中存在FDN，大多数病例报告发生在30至39周龄之间。所有受影响鸡群中的小母鸡均采用笼养方式，且大多数生产中的鸡群饲养在传统鸡笼中。大多数受FDN影响的鸡群在产蛋前至60周龄期间接受了12种以上不同的饲料配方。在大多数受影响的鸡群中，饲料中普遍添加了玉米干酒糟及其可溶物，并且所有鸡群都使用石灰石作为产蛋的钙源。大多数调查表明，球虫病和蛔虫寄生在受影响的生产鸡群中并非问题；然而，大多数受影响鸡群报告存在苍蝇和啮齿动物等害虫问题。此外，大多数受影响的养殖场在消毒前从未清洗过喂料器、鸡笼和鸡舍，这可能不足以预防FDN病原体的持续存在和传播。总之，大多数受FDN影响的鸡群描述了一些与肠道疾病相关的管理措施，包括梭菌相关性肠炎。需要进一步研究以确定本调查中确定的管理和健康措施是否代表FDN的风险因素。
