Abstract: This study attempted to isolate a novel C. perfringens (Cp) phage from poultry. Biological characteristics and genomic information have been analyzed, which can provide new strategy for Cp infection and control. A Cp phage was isolated and purified from broiler intestinal tissue samples by double-layer and single-layer plate methods. The morphology of the phage was observed by transmission electron microscope, and the MOI, one-step growth curve, pH and temperature tolerance characteristics, host range and antibacterial activity in vitro were analyzed. The genomic information was analyzed by genome sequencing, and finally the effect of phage on reducing the pollution of Cp was evaluated in a space simulated environment. The results showed that the electron microscope showed that the phage was a long tailed phage, the latent period was less than 20 min, the burst size was 28.5 PFU·cell^-1, and the best MOI was 0.01. It could specifically inhibit avian Cp strains, and the host range was as high as 83.72%. Genome analysis showed that the phage was a double stranded DNA phage with a total length of 41 590 bp and 59 open reading frames (ORF), of which 33 ORFs had certain homology with known functional proteins. The phage was named as vB_CpeS_SD72. The phylogenetic tree analysis of terminase small subunit showed that the phage had high homology with Clostridium phage vB CpeS-CP51. In the environmental control test, it was observed that the phage could inhibit 98.36% Cp at 30 min and nearly completely inhibited within 2 h. A novel Cp phage with strong lytic activity can effectively inhibit Cp contamination in the environment, which provide a powerful strategy candidate source for Cp pollution and control in food, animal breeding and livestock and poultry products.

Key words: C. perfringens phage, biological characteristics, genome, environmental inhibition