Table 1.
Isolation and identification of ILTV in ten clinical samples.
Figure 1.
Pathological anatomy of the larynx of ILTV infected chicken.
Larynx of the ILTV infected chicken was blocked by yellow caseous clots. Cutting the larynx open, the lumen of the larynx was narrow and the whole lumen was coated with yellow caseous membrane.
Figure 2.
The transmission electron microscopy of ILTV virions in chicken embryo kidney cells.
The chicken embryo kidney cells inoculated with the ILTV specimens for 48 h were treated by fixation, dehydration, embedding, polymerization, cutting into 50 nm sections, and then stained by 1% uranyl acetate and 1% lead citrate for transmission electron microscopy. The ILTV virions were distributed in cytoplasm of the chicken embryo kidney cells. The scale at the bottom-right of the picture was 2 µm.
Figure 3.
Amplification curve and standard curve of gB assay.
A: Amplification curves. Ten-fold dilutions of standard DNA ranging from 107 copies/µL to 101 copies/µL were used as standard controls. B: Standard curve (Y = −3.442X+42.76) (Error = 0.0654 and Efficiency = 1.952) was analyzed with the LightCycler 480 software 1.5.0.39. The concentration refers to the template copy number per reaction. Standards of DNA are indicated on the x-axis whereas the corresponding cycle threshold (Ct) values are presented on the y-axis.
Figure 4.
Sensitivity of the conventional PCR.
Ten-fold dilutions of standard DNA ranging from 107 copies/µL to 101 copies/µL were used to determine the sensitivity of the conventional PCR. The PCR products were stained with ethidium bromide. N: H2O; M: DL2000 DNA marker.
Figure 5.
Specificity of the real-time PCR.
Six other avian pathogens were used for the specificity test. Dilutions of 105, 104, 103, 102 were the standard DNA; 1: ILTV LJS09 strain DNA; 2–7: DNA and RNA samples of IBDV, CAV, REV, ARV, NDV, MDV; 8: H2O.
Table 2.
Reproducibility of real-time PCR.
Table 3.
Distribution of ILTV DNA in the tissues of infected chickens at different days post infection.
Figure 6.
Distribution and quantity of ILTV DNA in each tissue of the chickens at different days post infection.
Ten-week-old SPF chickens were inoculated intratracheally with 104 EID50 of ILTV strain LJS09. The viral loads were given as ILTV DNA copy number per g in each tissue. The tissues included the heart, liver, spleen, lung, kidney, larynx, tongue, thymus, glandular stomach, duodenum, pancreatic gland, small intestine, large intestine, cecum, cecal tonsil, bursa of Fabricius, and brain. A: The mean viral load of three chickens in the infection group and the standard deviation for each time point. B: The mean viral load of two chickens in the contact exposure group and the standard deviation for each time point.
Figure 7.
Immunohistochemical staining of the tissue sections at 14 dpi.
A: Tissues from the infection group. B: Tissues from the contact-exposure group. The immunohistochemical staining results revealed that ILTV was detected in the tissues including the heart, liver, spleen, kidney, larynx, thymus, small intestine, large intestine, bursa of Fabricius, and brain in the infection group and the contact-exposure group. 1. Heart: ILTV resided among the cardiac muscle fiber; 2. Liver: ILTV resided in hepatocytes; 3. Spleen: ILTV resided in splenocytes; 4. Kidney: ILTV resided in renal tubular epithelial cells; 5. Larynx: ILTV resided under the mucous membrane of the larynx; 6. Thymus: ILTV resided in ovarian medulla; 7. Small intestine: ILTV resided in intestinal gland epithelial cells; 8. Large intestine: ILTV resided in cells of lamina propria inner layer, intestinal mucosa epithelial cells, and intestinal gland epithelial cells; 9. Bursa of Fabricius: ILTV resided in epithelial cells of bursa of Fabricius; 10. Brain: ILTV resided in cerebral cortex.