Although the effects of diet on intestinal microbiotas have been well investigated,the effect of feeding time on the rhythm of gut microbiota remains uncertain.A 9-week feeding trial on Pelteobagrus fulvidraco was con...Although the effects of diet on intestinal microbiotas have been well investigated,the effect of feeding time on the rhythm of gut microbiota remains uncertain.A 9-week feeding trial on Pelteobagrus fulvidraco was conducted.Two triplicate groups of fish were fed identically either at 8:00(day)or at 20:00(night).After 9 weeks,three fish from each cage were sacrificed every 4 h for 24 h.The intestinal contents were analyzed using high-throughput sequencing.Three phyla(Fusobacteria,Proteobacteria,and Verrucomicrobia),and three genera(Cetobacterium,Akkermansia,and Clostridium)were dominant at every time point.Moreover,33.02%of detected amplicon sequence variants showed cyclical variations in fish fed at 20:00,and 3.47%in fish fed at 8:00.Among the top 20 genera,17 showed cyclical variations in the 20:00 group,and only two in the 8:00 group.Rhodobacter,Ralstonia,Mycobacterium,Lactococcus,Halomonas,Akkermansia,and Acinetobacter contributed more to the predicted functional pathways.Moreover,144 and 38 pathways exhibited daily cyclical fluctuations in fish fed at 20:00 and 8:00,respectively.Overall,certain intestinal microorganisms showed a circadian rhythm in P.fulvidraco,and this circadian rhythm was affected by shifted feeding times.展开更多
The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L （light）： 12D （dark） with lights on at 06：00...The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L （light）： 12D （dark） with lights on at 06：00 and off at 18：00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00：00, 04：00, 08：00, 12：00, 16：00 and 20：00 with 60 turtles each （Initial body weight 88.27 - 0.09 g）. Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate （SGR） and RNA/ DNA：SGR=t.1586RNA/DNA-0.7097 （r = 0.9328, P = 0.0066）. The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12：00 were the lowest from the six groups （P 〈 0.05）. Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight （FBW）, higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total.展开更多
Shifting the feeding time for fish from daytime to nighttime could alter their digestive behavior, disturb their metabolism, and may af fect immune-related genes. This study aimed to clone complement component C7 and ...Shifting the feeding time for fish from daytime to nighttime could alter their digestive behavior, disturb their metabolism, and may af fect immune-related genes. This study aimed to clone complement component C7 and analyze the different expression of C7 mRNA in fish fed during either the day or at night and then challenged with Aeromonas hydrophila infection. The P v-C7 cDNA of Pelteobagrus vachellii contained 2 647 bp with an open reading frame encoding a protein of 818 amino acids. Multiple sequences analysis indicated that P v-C7 included eight domains, which was similar to results for other species. Quantitative PCR analysis showed that P v-C7 was mainly expressed in the liver, spleen, intestine and head kidney tissues of healthy P. vachellii. Quantitative PCR analysis showed that C7 mRNA transcript in the liver, spleen and head kidney also increased significantly when the fish were fed at nighttime(20:00). In addition, the expression of Pv-C7 mRNA significantly increased with A. hydrophila challenge in the liver(48–96 h), spleen and head kidney(12–96 h) tissues of P. vachellii. Pv-C7 mRNA expression of the fish fed at nighttime showed significant higher than that in the fish fed at day time at 12–48 h in head kidney and 12–24 h in spleen. This study indicates that altering the feeding time from daytime to nighttime could increase P v-C7 mRNA expression, and feeding time may af fect the immune response involving C7.展开更多
基金Supported by the Sichuan Science and Technology Program(Nos.2021YFYZ0015,2023NSFSC0241)。
文摘Although the effects of diet on intestinal microbiotas have been well investigated,the effect of feeding time on the rhythm of gut microbiota remains uncertain.A 9-week feeding trial on Pelteobagrus fulvidraco was conducted.Two triplicate groups of fish were fed identically either at 8:00(day)or at 20:00(night).After 9 weeks,three fish from each cage were sacrificed every 4 h for 24 h.The intestinal contents were analyzed using high-throughput sequencing.Three phyla(Fusobacteria,Proteobacteria,and Verrucomicrobia),and three genera(Cetobacterium,Akkermansia,and Clostridium)were dominant at every time point.Moreover,33.02%of detected amplicon sequence variants showed cyclical variations in fish fed at 20:00,and 3.47%in fish fed at 8:00.Among the top 20 genera,17 showed cyclical variations in the 20:00 group,and only two in the 8:00 group.Rhodobacter,Ralstonia,Mycobacterium,Lactococcus,Halomonas,Akkermansia,and Acinetobacter contributed more to the predicted functional pathways.Moreover,144 and 38 pathways exhibited daily cyclical fluctuations in fish fed at 20:00 and 8:00,respectively.Overall,certain intestinal microorganisms showed a circadian rhythm in P.fulvidraco,and this circadian rhythm was affected by shifted feeding times.
基金supported by the National Natural Science Foundation of China (No.31172085)
文摘The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L （light）： 12D （dark） with lights on at 06：00 and off at 18：00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00：00, 04：00, 08：00, 12：00, 16：00 and 20：00 with 60 turtles each （Initial body weight 88.27 - 0.09 g）. Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate （SGR） and RNA/ DNA：SGR=t.1586RNA/DNA-0.7097 （r = 0.9328, P = 0.0066）. The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12：00 were the lowest from the six groups （P 〈 0.05）. Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight （FBW）, higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total.
基金Supported by the National Natural Science Foundation of China(No.31402305)the Natural Science Foundation of Sichuan Province(No.2017JY0161)the Educational Commission of Sichuan Province of China(No.14ZA0249)
文摘Shifting the feeding time for fish from daytime to nighttime could alter their digestive behavior, disturb their metabolism, and may af fect immune-related genes. This study aimed to clone complement component C7 and analyze the different expression of C7 mRNA in fish fed during either the day or at night and then challenged with Aeromonas hydrophila infection. The P v-C7 cDNA of Pelteobagrus vachellii contained 2 647 bp with an open reading frame encoding a protein of 818 amino acids. Multiple sequences analysis indicated that P v-C7 included eight domains, which was similar to results for other species. Quantitative PCR analysis showed that P v-C7 was mainly expressed in the liver, spleen, intestine and head kidney tissues of healthy P. vachellii. Quantitative PCR analysis showed that C7 mRNA transcript in the liver, spleen and head kidney also increased significantly when the fish were fed at nighttime(20:00). In addition, the expression of Pv-C7 mRNA significantly increased with A. hydrophila challenge in the liver(48–96 h), spleen and head kidney(12–96 h) tissues of P. vachellii. Pv-C7 mRNA expression of the fish fed at nighttime showed significant higher than that in the fish fed at day time at 12–48 h in head kidney and 12–24 h in spleen. This study indicates that altering the feeding time from daytime to nighttime could increase P v-C7 mRNA expression, and feeding time may af fect the immune response involving C7.
