Isolation and characterization of a Zobellviridae family bacteriophage, VPMCC6 and its protective effect against Vibrio harveyi in Penaeus monodon
摘要
Vibrio harveyi is responsible for several shrimp diseases such as luminous vibriosis, hepatopancreas necrosis, red body, and black spot disease, which can cause substantial mortality in shrimp. Due to the increasing prevalence of antibiotic-resistant pathogenic infections, bacteriophage therapy is being considered as a potential alternative for disease treatment. In this study, a Vibrio-infecting bacteriophage VPMCC6 was isolated from an infected shrimp aquaculture pond. VPMCC6 bacteriophage had an icosahedral head (43.51 ± 1.07 nm) and a short tail (14.60 ± 2.13 nm). This bacteriophage produced 24 PFU/cell on its propagation strain V. harveyi S2A and could clearly lyse the host bacteria after 3 h of bacteriophage addition. Whole genome sequence analysis confirmed that the bacteriophage VPMCC6 genome had no tRNA and no virulence or antibiotic resistance genes. Moreover, we evaluated the effectiveness of bacteriophage therapy in controlling vibriosis in Penaeus monodon. After vibriosis induction in P. monodon using 1 × 106 CFU/ mL of V. harveyi S2A in laboratory aquarium, the infected shrimp were treated with Vibrio-infecting bacteriophage VPMCC6 at MOI 1. Results showed that bacteriophage VPMCC6 significantly reduced the mortality of P. monodon (reduction of 54.76% compared to the infected group) and controlled V. harveyi infection in shrimp culture water. Histopathological analysis showed that the treatment group displayed less hepatopancreatic necrosis and reduced tissue damage. These findings suggest that bacteriophage VPMCC6 is a promising biocontrol agent against V. harveyi in P. monodon aquaculture.