ILT
Poultry

ILT

ILT is an enzyme immunoassay(EIA) for the detection of specific IgG antibodies against Infectious Laryngotracheitis(ILT) virus antigens in poultry sera of vaccinated or convalescent animals of the disease.

General Information

Infectious Laryngotracheitis is a disease caused by Infectious Laryngotracheitis (ILT)virus, belonging to the Herpesviridae family.

It is a very common disease in countries with industrial poultry farming, and causes important losses.

The disease may manifest in an acute or mild form. depending on the virus strain virulence. Symptoms usually appear 6-15 days after infection.
In acute infections mortality rates are very high.

Mild infections usually don’t cause significant mortality rates, but they favor tremendously the category of circulating secondary agents, such as Haemophilus sp., Mycoplasma sp., Pasteurella sp., etc.
The animals which survive infections, can expel virus during more than 1 year after infection, and they can cause recurrent infections in new lots of poultry which are bought in the exploitation.

Another important aspect of this virus is its latency in poultry, that can sharpen by any stress factor ; meaning a grave risk of virus spreading from complementary poultry lots to industrial poultry lots.
One must seriously take this factor into account for disease epidemiology control.

Principle of the test

The Cypress Diagnostic ILT test is based on the principle of an enzyme Immunoassay (EIA). The assay system utilizes an inactivated specific antigen. This specific antigen is coated on the microtiter well.
First, the test sample or controls are allowed to react with the solid phase specific antigen. If there are specific antibodies, they will bound to the antigen. After 1 hour incubation at 37°C, the wells are washed with the washing solution to remove unbound material.
In a second step, an Anti-Chicken IgG/HRPO conjugate is added to the wells resulting in the specific antibody against infectious Laryngotracheitis virus being sandwiched between the solid phase antigen and enzyme conjugate antibody. After 1 hour incubation at 37°C, the wells are washed with the washing solution to remove unbound material.
A substrate/chromogen solution is added and incubated 15 minutes , resulting in the development of a blue color in the wells where a complex Antigen/ Anti-ILT virus antibody/Anti-Chicken IgG-HRPO conjugate was formed previously.
The color development is stopped with the addition of the stop reaction solution and the color turns yellow. The yellow color is measured spectrophotometrically at 450 nm.
The concentration of poultry specific IgG antibody against Infectious Larygotracheitis(ILT) virus is proportional to the color intensity of the test sample.

Rev.09.95

© 1999 HLS Veterinary Biological Products, Inc.