Transcriptome study of ammonia nitrogen and WSSV stress on Litopenaeus vannamei at specific temperature
In order to determine the critical concentration of ammonia nitrogen leading to WSSV outbreak, the survival rate of shrimp with latent WSSV infection under ammonia nitrogen stress was studied. When the ammonia nitrogen concentration was 20, 30, 40, 50 mg/L, respectively, shrimp in the PBS group began to die at 48 h, 36 h, 36 h, 24 h, respectively, and those in the latent WSSV group began to die at 36 h, 24 h, 24 h, 24 h, respectively. In normal seawater, ammonia nitrogen concentration; At 0.05 mg/L, shrimp in the PBS group and latent WSSV group did not die. When the ammonia concentration was 50 mg/L, the final survival rate of shrimp in the PBS group was 50% at 144 h, and the final survival rate of shrimp in the WSSV group was 40%. When ammonia nitrogen concentration was 20 mg/L, the final survival rate of shrimp in the PBS group was 80% at 144 h, and the final survival rate of shrimp in the WSSV group was 66.7%. It is worth noting that when the ammonia concentration is 10 mg/L, the final survival rate of shrimp in the PBS group at 144 h is 100%, which is significantly higher than the final survival rate of 90% in the WSSV group. The results showed that high concentration of ammonia nitrogen could not only inhibit the immune system of shrimp, but also increase the severity of WSSV infection.