INNATE IMMUNE RESPONSES OF ILT VIRUS INFECTION IN LAYER AT PRODUCTION STAGE IN IRAQ

Abstract

Since 2011, there have been epidemics of respiratory infection in Iraq's laying hen farms, including hemorrhage tracheitis, which closely resembles laryngotracheitis and exhibits symptoms such as symptoms and lesions, respiratory issues, and swelling. Infectious laryngotracheitis (ILT) in layers hen farms in Iraq had to be molecularly identified and determined, together with viral load and innate immune responses of gene transcription (INF-γ, IL1, IL6, and IL10). A total of 40 samples 20 trachea and 20 lungs were taken from various suspect contaminated layer flocks of Iraqi farms (age: 33 weeks). Real-time PCR results showed that 10 samples from both tissues tested positive for the ILT virus. The highest viral load, 5.52×103 copies/L viral nucleic acid, was found in tracheal tissue at 7 dpi, whereas the lowest viral load, 1.65×103 copies/L viral nucleic acid, was found in lung tissues. At 3 and 7 days after infection, the expression of INF-γ, IL1 and IL6 was significantly higher there in tracheal tissues (P≤0.05) than in the lung tissues, indicating a down regulation of these three molecules. In both organs at the same time, there was no up regulation of IL10. The findings of this study show that ILTv up-regulates the transcription of several cytokines in the trachea, including INF-γ, IL1, and IL6, during various stages of the cytokine production process.