avian & livestock assay data sheet
Infectious
bursal disease virus (IBDV)
Test code:
S0084
-
Ultrasensitive qualitative detection of infectious bursal
disease virus by reverse transcription coupled real time
polymerase chain reaction.
Infectious bursal disease virus (IBDV), which causes the
notorious infectious bursal disease, is a birnavirus that can be
readily isolated from the bursa of Fabricius of infected birds,
and sometimes also from other organs. Infected birds can shed
the virus in their feces. The virus is very stable in the
environment and can readily be transmitted on fomites, so it is
difficult to eradicate from premises.
IBD is very contagious. Symptoms depend on age, breed, and
virulence of the strain of the virus. Infections may be
subclinical or clinical. Chickens are most susceptible to the
infection at 3-6 weeks of age, but severe infections have
occurred in Leghorn chickens up to 18 weeks old. Infections
before 3 weeks of age are usually subclinical.
Early subclinical
infections are the most economically important form of
the disease. They cause severe, long-lasting immunosuppression
due to destruction of immature lymphocytes in the bursa of
Fabricius, thymus, and spleen. Growth is significantly reduced,
and even subclinical infected chickens can spread the disease.
In clinical infections,
onset of the disease is sudden, usually 3-4 days after contact
with the virus. Chickens exhibit severe prostration,
incoordination, watery diarrhea, soiled vent feathers, vent
picking, and inflammation of the cloaca. Mortality rate can
exceed 20%. Infected
chickens may recover in less than 1 week after the onset of the
symptoms, with broiler weight gain delayed by 3-5 days. The
presence of maternal antibody will modify the clinical course of
the disease.
Traditional methods for diagnosis of IBDV infection include agar
gel precipitation, virus neutralization, and enzyme-linked
immunosorbent assay (ELISA). These tests are designed to measure
levels of antibodies to IBDV. However, these techniques are not
very sensitive, and the presence of maternal antibody may
complicate interpretation. Molecular detection by PCR can
provide rapid, sensitive and specific detection of the virus
(Lee et al., 1994).
Utilities:
-
Help confirm the disease causing agent
-
Environmental monitoring
-
Help ensure that flocks are free of IBDV
-
Early prevention of spread of the virus among flocks
-
Minimize human exposure to the virus
-
Safety monitoring of biological products and vaccines that
derive from poultry
References:
Lee, L. H., Ting,
L. J., Shien, J. H and Shieh, H. K. (1994) Single-tube,
noninterrupted reverse transcription-PCR for detection of
infectious bursal disease virus. J. Clin. Microbiol. 32:
1268-1272.
Specimen requirements: 0.2 ml feces, or
cloacal swab, or respiratory swab, or 0.2 ml whole blood in EDTA
(purple top) tube, or 0.2 ml fresh, frozen
or fixed tissue.
Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.
For all specimen types, if there will be a delay in shipping, or
during very warm weather, refrigerate specimens until shipped
and ship with a cold pack unless more stringent shipping
requirements are specified. Frozen specimens should be shipped
so as to remain frozen in transit. See
shipping instructions for
more information.
Turnaround time: 2 business days
Methodology: Reverse transcription
coupled real time PCR
Normal range: Nondetected