El-Tholoth Mohamed, Abou El-Azm Kamel I
Department of Virology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt.
Department of Poultry Diseases, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt.
Trop Anim Health Prod. 2019 Jun;51(5):1065-1071. doi: 10.1007/s11250-018-01783-0. Epub 2019 Jan 5.
A case-control study was performed to assess prescence of inclusion body hepatitis (IBH) caused by fowl adenoviruses (FAdVs) at Kafr EL-Shiekh Governorate, Egypt, during spring, 2017. The case group consisted of 100 liver and spleen samples collected from 10 broiler chickens flocks (10 samples from each flock) suspected to be infected with IBH depending on clinical manefestations and necropsy examination. Controls were randamly selected from chickens without clinical sings or evidence of the disease on postmortem examination. Molecular screening of the disease disease in collected samples based on the DNA polymerase gene of FAdVs was carried out. Furthermore, the DNA polymerase gene sequence was determined and analyzed with published reference sequences on GeneBank. Respectively, enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) were used to confirm existence of co-infection with chicken infectious anemia virus (CIAV) and/or infectious bursal disease virus (IBDV in flocks involved in the study. Using PCR, FAdV genome was detected in seven flocks in the case group and one in the control group. FAdV identified in this study revealed close genetic relationship with FAdVs-D previously identified in UK and Canada, suggesting potential virus transmission from these countries. All tested serum samples from diseased chickens were positive for CIAV infection via ELISA while none of the collected bursa of Fabricius samples tested IBDV positive by RT-PCR. Therefore, results obtained from the current study highlighted the importance of implementation of control measures against FAdV and CIAV in Egyptian poultry flocks. This study opens the door for future work toward specific identification of FAdV serotypes circulating in Egyptian poultry farms and molecular characterization of the virus based on hexon gene or full genome sequencing for better understanding of genetic diversity among FAdVs in Egypt at higher reolution.
2017年春季，在埃及卡夫尔谢赫省开展了一项病例对照研究，以评估由禽腺病毒（FAdVs）引起的包涵体肝炎（IBH）的存在情况。病例组由从10个肉鸡群中采集的100份肝脏和脾脏样本组成（每个鸡群10份样本），这些鸡群根据临床表现和尸检检查怀疑感染了IBH。对照组是从死后检查无临床症状或疾病迹象的鸡中随机选取的。基于FAdVs的DNA聚合酶基因对采集样本进行了该疾病的分子筛查。此外，测定了DNA聚合酶基因序列，并与GenBank上公布的参考序列进行了分析。分别使用酶联免疫吸附测定（ELISA）和逆转录聚合酶链反应（RT-PCR）来确认参与研究的鸡群中是否存在与鸡传染性贫血病毒（CIAV）和/或传染性法氏囊病病毒（IBDV）的共同感染。通过PCR检测到病例组的7个鸡群和对照组的1个鸡群中存在FAdV基因组。本研究中鉴定出的FAdV与先前在英国和加拿大鉴定出的FAdVs-D显示出密切的遗传关系，表明可能存在来自这些国家的病毒传播。所有患病鸡的检测血清样本通过ELISA检测CIAV感染均呈阳性，而采集的法氏囊样本通过RT-PCR检测IBDV均为阴性。因此，本研究获得的结果突出了在埃及家禽群中实施针对FAdV和CIAV的控制措施的重要性。本研究为未来的工作打开了大门，以便更具体地鉴定在埃及家禽养殖场中传播的FAdV血清型，并基于六邻体基因或全基因组测序对病毒进行分子特征分析，以更高分辨率更好地了解埃及FAdVs之间的遗传多样性。
