What is the avian adenovirus ?
The adenovirus is an opportunistic virus. The virus is normally mild and may be present in the body while being perfectly controlled by a normal immune system. On the other hand, when the immune system is weakened, the virus will cause serious complications. However, in young birds, this virus is often very virulent since the mortality rate is often close to 100%. The virus that infects birds is called Fowl Adenovirus and includes 12 different serotypes. As there are no effective vaccines or treatments for this viral disease, early detection of infected birds is a key factor in controlling this disease.
The symptoms are breathing difficulties, anorexia, anemia and signs of depression. In young bird, adenovirus causes alterations in the Fabricius bursa, a small gland very important for the constitution of the immune system of the bird.
The transmission is oral, by inhalation. The “healthy carrier” parents infected with the virus without expressing the symptoms can transmit the virus to their chicks during the regurgitation of food. The adenovirus replicates in the nuclei of infected cells
Cells infected by fowl adenovirus
The virus is resistant to high temperatures and some disinfectants. The Virkon and the formaldehydes are however effective.
Screening and interpretation of results
The viral particles of adenovirus are circular, about 40-50 nm in diameter. They are double-stranded and contain 4,981 base pairs.
The classical PCR is a sensitive and specific method, which makes it possible to highlight the viral DNA present in the blood or in the epithelial cells of the cloaca of the bird. However, the laboratory Genimal Biotechnologies realizes an optimized protocol of detection of the adenovirus based on an innovative technology of nested touchdown PCR. This method allows for even more reliable results.
Thanks to the innovative nested touchdown PCR technique used by Genimal Biotechnologies, the result of the adenovirus screening test can be negative or positive. A negative result only means that the sample analyzed does not contain any virus. A positive result means that the bird is infected with adenovirus.
In case of positive result, the bird should be quarantined and all surfaces disinfected.
Type of sample
Here is the list of the different types of samples that are accepted for this test :
- Dry blood on paper
- Cloacal swab
- Blood in dry tube
Certificate example for the test : Avian adenovirus
Click on the example certificate below to open it.
Caterina KM, Frasca S Jr, Girshick T, Khan MI. Development of a multiplex PCR for detection of avian adenovirus, avian reovirus, infectious bursal disease virus, and chicken anemia virus. Mol Cell Probes. 2004 Oct;18(5):293-8.
Dinesh Mittal, Naresh Jindal,corresponding author Ashok Kumar Tiwari, and Raj Singh Khokhar. Characterization of fowl adenoviruses associated with hydropericardium syndrome and inclusion body hepatitis in broiler chickens. Virusdisease. 2014 Jan; 25(1): 114–119.
Xie, Zhixun & A. Fadl, Amin & Girshick, Theodore & Khan, Mazhar. (1999). Detection of Avian Adenovirus by Polymerase Chain Reaction. Avian diseases. 43. 98-105. 10.2307/1592767.