Evaluation of the matrix effect of thermophilic anaerobic digestion on inactivation of infectious laryngotracheitis virus using real-time PCR and viral cell culture

The matrix effect of the thermophilic anaerobic digestion (TAD) process on inactivation of infectious laryngotracheitis virus (ILTV) was evaluated. Viral cell culture and real-time PCR were used for assessing removal of the viral infectivity and degradation of viral DNA, respectively. Results showed that the TAD-derived matrix alone can inactivate the virus and destroy the nucleic acid helix core of ILTV in a time-and- dose-dependent manner. No cytopathogenic effect (CPE) was observed in the cells exposed to ILTV pre-treated with TAD matrix for 1.5 h in experiment 1 and for 16 h in experiment 2. There was a significant statistical difference between TAD matrix treated and non-treated cultures (p < 0.001, Chi-test). Amplifiable ILT viral DNA was reduced 2.27 log by 1.5 h-treatment and was not present by 16 h-treatment with TAD matrix, indicating complete viral DNA fragmentation. The TAD process is an environmentally friendly way for disposing of poultry biowaste and carcasses.