DEVELOPMENT OF A POLYMERASE CHAIN-REACTION AND A NONRADIOACTIVE DNA-PROBE FOR INFECTIOUS LARYNGOTRACHEITIS VIRUS

The polymerase chain reaction (PCR) was developed using infectious lar yngotracheitis virus (ILTV) primers made from a portion of the ILTV th ymidine kinase gene. DNA from various IL?II field isolates, from the U SDA challenge strain of ILTV, and from commercial ILTV vaccines was sp ecifically amplified. No amplification occurred using template DNA fro m uninfected chicken-embryo liver cells (CELC), several nonavian alpha herpesviruses, Mycoplasma gallisepticum, Mycoplasma synoviae, Pasteure lla hemolytica, Escherichia coli, a group I avian adenovirus, fowl pox virus, or a psittacid herpesvirus. The 647-base pair-amplified ILTV PC R product was labeled to create a nonradioactive, biotinylated DNA pro be. Hybridization using the probe detected ILTV DNA. Both PCR and hybr idization yielded positive results with ILTV DNA bur nor with the DNA of other pathogens. Hybridization was specific for ILTV using a string ent salt solution for a 30-min wash step or a somewhat less stringent salt solution for a 60-min wash step. However, slight hybridization oc curred with CELC DNA when the less stringent salt solution was used in a 30-min wash step.