This study aimed to investigate the effects of different humidity levels on the growth performance, slaughter performance, and meat quality of Pekin ducks through the artificial control of humidity, and to identify the suitable environmental humidity for Pekin duck growth. A completely randomized single-factor design was employed, selecting 144 newly hatched male Pekin ducks with healthy and similar BW (body weight) (60.92 g ± 4.38). These ducks were randomly assigned to four groups (A (RH (relative humidity) = 60%), B (RH = 67%), C (RH = 74%), D (RH = 81%)), with 12 ducks and 3 replicates in each group. The ducks were raised in a climate-controlled room for 42 days with ad libitum access to feed and water. BW and feed intake were measured every 3 days, and slaughter performance and meat quality were assessed at 42 days. There was no significant difference in the ADG (average daily gain) from 1 to 21 days (p > 0.05). The ADFI (average daily feed intake) of Group D was significantly lower than that of Groups A, B, and C (p < 0.05), with no significant differences between Groups A, B, and C (p > 0.05). At 42 days, the BW, ADG, and ADFI of Groups A and C were significantly higher than those of Group D (p < 0.05), with no significant differences among Groups A, B, and C (p > 0.05). Group C had a significantly higher breast muscle weight, breast muscle ratio, liver weight, and liver index than Groups B and D (p < 0.05), with no significant differences between Groups A, B, and D (p > 0.05). The meat shear force in Group C was significantly lower than that in Groups A, B, and D (p < 0.05). The L* (brightness) of Group C was significantly lower than that of Group A (p < 0.05), and the a* (redness) value of Group C was significantly higher than that of Groups A and B (p < 0.05), with no significant difference compared to Group D (p > 0.05). Group B had a significantly higher cooking loss than Groups A, C, and D (p < 0.05), with no significant differences among Groups A, C, and D (p > 0.05). Under 26 °C conditions, Pekin ducks perform best in terms of the production performance and feed efficiency, with high-quality meat, especially when reared at 74% humidity.

Snakehead vesiculovirus (SHVV), a strain of negative-stranded RNA viruses extracted from sick snakehead fish (Ophicephalus striatus), may pose a threat to the health of snakehead fish. Previous research has proved that the replication of SHVV can be significantly inhibited by glutamine starvation. To study how glutamine starvation inhibits SHVV replication, channel catfish ovary (CCO) cells with SHVV cultivated in the glutamine-free medium or the complete medium were used to investigate the differentially expressed proteins (DEPs). The results showed that 124 up-regulated and 246 down-regulated proteins were involved in many viral replication physiological processes, such as autophagy, post-translational modifications machinery, and functional pathways, including the PI3K-Akt signaling pathway and mTOR signaling pathway. Furthermore, a few proteins, such as Akt and Hsp90, which have been confirmed to be involved in the replication of RNA viruses, were also significantly differentially expressed. Taken together, our study demonstrated that glutamine starvation affects various functional pathways and the expression of some key proteins related to RNA viral replication, which will benefit future studies on the replication mechanisms of SHVV and the prevention of SHVV infection.