Evaluation Of Ecological Health And Aquaculture Efficiency Of Pelteobagrus Fulvidraca Pond Based On Different Feeding Modes

In this paper,nine productive Pelteobagrus fulvidraco ponds（A1,A2,B1,B2,C1,C2,D1,D2 and E1）in 8 districts of Guilin Small Pond Agriculture and Animal Husbandry Company were studied,Which feeding with different periodic intermittent starvation.Four experimental groups（A,B,C and D）were set up.The intermittent starvation cycles were 3,5,7 and 10 days,with one replicate in each group,and a"normal feeding pond"as the control group（Group E）.In this paper,the spatial and temporal dynamics of plankton population structure and main p Hysical and chemical factors of aquaculture water quality in experimental ponds were studied,and the ecological health status of experimental ponds and the breeding efficiency of Pelteobagrus fulvidraco were evaluated.The main research results are as follows:1.Through principal component analysis（PCA）,p H,SD,WT,COD_Mn and DO were selected as the main water quality indicators of Pelteobagrus fulvidraco aquaculture waters.Analysis of the main water quality indicators found that the shorter the starvation feeding interval,the more conducive to regulating and controlling the p H environment in Pelteobagrus fulvidraco aquaculture ponds.During the experimental period,the water quality of each experimental group was weakly alkaline,which was more suitable for the growth of Pelteobagrus fulvidraco.The average p H of group A was 1.87%,2.36%and 2.61%lower than that of group D（starvation at 10 days interval）,group C（starvation at 7 days interval）and group B（starvation at 5 days interval）.2.Among the four experimental ponds,group D had the highest p Hytoplankton richness（number of genera）,reaching 40 genera,which was 7.5%,10%,15%higher than group B,group D and group A,respectively,and 10%higher than the control group;The biomass of p Hytoplankton in group C was the highest,which was 46.15%,3.08%,16.92%higher than that in group B,group D and group A,and 27.69%higher than that in control group;The highest p Hytoplankton density group was group B,which was 52.98%,37.23%,42.25%higher than group C,group D and group A,and 33.12%higher than the control group;The highest number of zooplankton genera in group A was 15.79%,37.23%and 42.25%higher than that in group C,group B and group D,respectively,and 33.12%higher than that in control group;The highest biomass of zooplankton in group C was 46.15%,3.08%and 16.92%higher than that in group D,group B and group A;The highest density of zooplankton in group C was 36.49%,48.70%and 59.62%higher than that in group B,group D and group A,respectively,and 65.73%higher than that in control group.At the overall level of plankton richness and diversity,group C（starvation at 7 days interval）>group A（starvation at3 days interval）>group B（starvation at 5 days interval）>group D（starvation at 10 days interval）.3.p Hytoplankton Diversity Index as an Important Indicator of Water Nutrition Status to Evaluate Water Quality of Experimental Ponds（Margalef Richness index（D’）,Shannon-Wiener diversity index（H’）and Pielou evenness index（J’））.At D’level,group A was the highest（1.44%）and group B was the lowest（1.39）.Group A was 0.21%,1.60%and3.41%higher than group D,group C and group B,respectively.At H’level,group C was the highest,reaching 3.63%,while group D was the lowest,reaching 3.27%,Compared with group A,group B and group D,group C increased by 5.52%,8.00%and 9.68%respectively.At J’level,group C was the highest,reaching 0.83%,group D was the lowest,reaching 0.77%,Compared with group A,group B and group D,group C increased by 4.57%,5.29%and 8.05%respectively.Based on p Hytoplankton diversity index,the water quality of group C（starvation at7 days interval）was better than that of group A（starvation at 3 days interval）and group B（starvation at 5 days interval）than that of group D（starvation at 10 days interval）.4.The water quality of each experimental group was evaluated by p Hytoplankton integrity index（P-IBI）.The water quality of group A,group B and group C was better,followed by group D,and the water quality of control group was the worst.The score of P-IBI from big to small was group B>group A>group C>group D.The average P-IBI score of group B was the highest,which was 4.60%,6.75%and 10.90%higher than that of group A,group C and group D,respectively.Based on the plankton integrity index,the water quality of group B（starvation at 5days interval）was better than that of group A（starvation at 3 days interval）and group C（starvation at 7 days interval）than that of group D（starvation at 10 days interval）.5.Grey correlation analysis showed that WT and COD_MN were closely related to P-IBI score,while p H score had relatively low correlation with P-IBI score in different feeding ponds.The correlation degree between P-IBI index and water quality factors in group B pond with the best water quality was TN>TP>WT>SD>COD_Mn>Chla>DO>NO₂-N>BOD₅>p H>NH₃-N,The correlation degree between P-IBI index and water quality factors in group D pond with the worst water quality status was WT>TN>COD_Mn>TP>NH₃-N>DO>BOD₅>Chla>SD>p H>NO₂-N.Compared with the control group,different intermittent starvation feeding modes have obvious improvement effect on the water quality of Pelteobagrus fulvidraco ponds.In view of the large area of culture carrier ponds（each pond area is more than 10 000 m²）in this study,and they are all conventional productive ponds,the results of health assessment of the aquaculture water body have certain reference value for formulating the health improvement scheme of Pelteobagrus fulvidraco culture ponds.6.Intermittent starvation can stimulate the compensatory growth potential of Pelteobagrus fulvidraco.At the growth level of body weight and body length,Pelteobagrus fulvidraco in group C pond obtained better compensatory growth effect,followed by group D pond,group B pond and group A pond.Compared with starvation feeding modes in different intermittent periods,the daily weight growth rate of group C（starvation at 7 days interval）was 32.27%,11.52%and 8.54%higher than that of group D（starvation at 10 days interval）,group B（starvation at 5 days interval）and group A（starvation at 3 days interval）.At the level of growth rate of body length,group C increased by 0.27%,0.08%and0.03%compared with group D,group B and group A,respectively.7.Feeding mode B（starvation interval of 5 days）could reduce feed energy consumption and improve the ecological benefits of farming.The feed coefficient of Pelteobagrus fulvidraco was 1.45,The feed coefficient of group B was 5.84%,9.94%and 12.65%lower than that of group A,group C and group D.The aquaculture water body reaches the water quality of Class III and meets the standards of"centralized domestic water,surface water source protection area,fish and shrimp wintering grounds,etc."The water quality of group B（starvation at 5 days interval）was better than that of group A（starvation at 3 days interval）,group C（starvation at 7 days interval）and group D（starvation at 10 days interval）.8.Effects of intermittent starvation on p Hysiological and biochemical indexes of Pelteobagrus fulvidraco（1）The activities of antioxidant enzymes in group B（starvation at 5days interval）were the highest,and the activities of SOD and C AT were108.23U/mgprot and 607.62U/mgprot,respectively.Compared with group C,group A and group D,the activities of SOD and C AT were increased by 7.12%,11.48%,10.12%and 0.74%,3.51%and 6.44%.（2）Amylase（AMS）,lipase（LPS）and protease（TPS）activities in group C（starvation at 7 days interval）were the highest,which were0.93U/mgprot,85.85U/mgprot and 246.022U/mgprot,respectively.Compared with group D,group B and group A,AMS activities increased by 1.01%,23.66%,27.95%,LPS activities increased by 0.23%,0.72%,9.70%,TPS activities increased by 7.00%,10.06%and 16.13%.