Vaccinations, surveillance, quarantine, and disposal of the infected poultry are the common strategies for prevention and control of the highly infectious poultry diseases; however, many pathogens still persist and are potential causes threatening the nationwide spread of poultry diseases. A strict biosecurity strategy including disinfection is the key to control the spread of avian pathogens, such as the Newcastle disease virus (NDV). It is important to select and use the disinfectants whose efficacy and the effective concentrations against the specific pathogens are known. Therefore, in the present study, we evaluated the virucidal efficacy of five active substances of commercial disinfectants, namely potassium peroxymonosulfate (PPMS), sodium dichloroisocyanurate (NaDCC), glutaraldehyde (GLT), benzalkonium chloride (BZK), and didecyldimethylammonium chloride (DDAC), that are used against NDV. Further, we validated the efficacy of eight pre-approved disinfectants. The minimal virucidal concentrations of the active substances against NDV were as follows: PPMS, 2.50 g/L; NaDCC, 2.00 g/L; GLT, 0.40 g/L; BZK, 2.00 g/L, and DDAC, 1.00 g/L. Furthermore, all the eight disinfectants were found to be effective against NDV at the recommended concentrations, thereby confirming that the active substances are functional against NDV. This is the first study reporting the virucidal activity of the active substances of commercial disinfectants against NDV, in accordance with the Animal and Plant Quarantine Agency guidelines, in South Korea. The results of the virucidal efficacy testing of chemical disinfectants from this study will help poultry industries implement improved strategies for controlling infection.

The present study was aimed to evaluate the influence of glutaraldehyde (GA) concentration on multiple electron microscopic (EM) immunostaining using pre-embedding peroxidase and post-embedding immunogold method. Influence of various concentrations of GA included in the fixative on immuoreactivity was assessed in the multiple immunostaining using antisera against anti-transient receptor potential vanilloid 1 (TRPV1) for peroxidase staining and anti-GABA for immunogold labeling in the rat trigeminal caudal nucleus. Anti-TRPV1 antiserum had specificity in pre-embedding peroxidase staining when tissues were fixed with fixative containing paraformaldehyde (PFA) alone. Immunoreactivity for TRPV1 was specific in tissues fixed with fixative containing 0.5% GA at both perfusion and postfixation steps, though the immunoreactivity was weaker than in tissues fixed with fixative containing PFA alone. Tissues fixed with fixative containing 0.5% GA at the perfusion and postfixation steps showed specific immunogold staining for GABA. The results of the present study indicate that GA concentration is critical for immunoreactivity to antigens such as TRPV1 and GABA. This study also suggests that the appropriate GA concentration is 0.5% for multiple immunostaining with peroxidase labeling for TRPV1 and immunogold labeling for GABA.