a comparison of sensitivity analysis of rrt-pcr and rt-pcr techniques for diagnosis of avian newcastle disease virus

background: newcastle disease is one of the most serious viral diseases in the poultry worldwide. objectives: since the traditional strategies have been hardly effective in controlling the disease, the purpose of this study was to introduce new methods for early and rapid diagnosis of newcastle. the present study helps to reduce further damage to the poultry industry. methods: rna extraction was performed, using rnease mini kit, according to the manufacturer’s instructions. extracted rna with 68.23×109 copy numbers was prepared as serial dilutions of 100 μl for rt-pcr and rrt-pcr reactions. rrt-pcr and rt-pcr were performed, using commercial kit and rnease mini kit, respectively.  results: results showed that amplification was done according to prepared dilution equal 10-34 for rrt-pcr reaction and a visible band observed on 1.5% agarose gel up to 10-20 for rt-pcr reaction. based on the results observed, rrt-pcr and rt-pcr reactions are able to detect 10-34 and 10-20 copy numbers of primary sample, respectively. conclusions: the sensitivity of rrt-pcr reaction is almost twice compared with rt-pcr reaction, also rrt-pcr reaction is able to diagnose newcastle disease virus in infected samples with 10,000 copy numbers of the rna virus less than rt-pcr.