Evaluation On Ecological Health And Culture Efficiency Of Pelteobagrus Fulvidraco Pond Based On Different Species Structure

As a kind of omnivorous benthic fish,Pelteobagrus fulvidraco has low utilization rate of plankton water and difficulty in water quality regulation.In the stingray breeding pond,Silver carp and Bighead carp can effectively control plankton and purify the water,while at the same time making full use of the water space and improving the economic benefits of farming.In this experiment,on the basis of"mixed culture experience",five productive ponds of Guilin small pond culture company were taken as the research object,and the study on the breeding of silver carp and bighead carp in yellow catfish pond was carried out.Silver carp（silver carp）and bighead carp（bighead carp）were mixed at the ratios of9:1,7:3,5:5,3:7 and 1:9 in the ponds with the same stocking density.The effects of different ratios of silver carp and bighead carp on the ecological health and culture efficiency of the ponds were studied.The dynamic changes of physical,chemical and biological factors in aquiculture ponds of different species structure were analyzed by real-time monitoring,as well as the growth index,physiological and biochemical index of the main breed of Pelteobagrus fulvidraco.To evaluate the ecological health and culture efficiency of five different species of Pelteobagrus fulvidraco culture ponds.The main research results are as follows:1.Based on the water quality evaluation of TP,the water quality of pond 5（silver carp:bighead carp=1:9）was better than that of others,that is,in a certain range of"density ratio",the main raising yellow carp was 1:9"silver carp:bighead carp"get better"phosphorus reduction"effect,the second is the"silver carp:bighead carp"ratio of 3:7.Based on the water quality evaluation of NH₂-N and NH₃-N,the water quality of pond 2（silver carp:bighead carp=7:3）was better than others,that is,in a certain range of"density ratio",the main raising yellow carp was7:3"silver carp:bighead carp"get better"phosphorus reduction"effect,the second is the"silver carp:bighead carp"ratio of 1:9.Based on the water quality evaluation of COD_Mnand BOD₅,the water quality of 4#pond（silver carp:bighead carp=3:7）was better,that is,3:7 of"silver carp:bighead carp"was better than others,which could reduce COD and BOD5 in aquaculture water to a certain extent,The second was"silver carp:bighead carp"ratio of 1:9.2.Based on grey relational analysis,the water quality of pond 3#（silver carp:bighead carp=5:5）was mainly of classⅢand classⅡ,and the ecological health of water body was better than others.The second was 2#pond（silver carp:bighead carp=7:3）and 1#pond（silver carp:bighead carp=9:1）,4#pond（silver carp:bighead carp=3:7）and 5#pond（silver carp:bighead carp=1:9）were the worst.3.At the level of phytoplankton genera,1#pond>5#pond>3#pond>2#pond>4#pond.Based on the diversity level of phytoplankton genera,the diversity level of phytoplankton in pond 1（silver carp:bighead carp=9:1）was higher than that in pond 5（silver carp:bighead carp=1:9）and pond 3（silver carp:bighead carp=5:5）.2#pond（silver carp:bighead carp=7:3）and 4#pond（silver carp:bighead carp=3:7）increased 3.2%,6.4%,9.7%and 12.9%,respectively.There was no significant difference among the ponds（P>0.05）.4.Based on the Shannon-Wiener diversity index,（H）,Pielou evenness index（J）and Margalef richness index（D）,the water quality of aquaculture ponds was evaluated.The H,J,and D values of 1#pond（silver carp:bighead carp=9:1）were 2.95,0.70 and 1.35,respectively.The diversity level of phytoplankton is better,the water body is clean,the diversity level of phytoplankton in pond 4（silver carp:bighead carp=3:7）is poor,and the pollution of water body is relatively large.5.Based on the ecological health assessment of plankton integrity index（P-IBI）experimental ponds,the ecological health status of 1#pond,2#pond,3#pond,4#pond and 5#pond was respectively 5"healthy"and 4"healthy"1"poor",4"Health"1"sub-health",3"health"2"sub-health"and 4"health"1"poor",the average P-IBI scores were 5.88,4.39,4.69,4.52 and 4.72,respectively,1#pond>5#pond>3#pond>4#pond>2#pond,That is,ecological health assessment based on plankton integrity index（P-IBI）,1#pond（silver carp:bighead carp=9:1）>5#pond（silver carp:bighead carp=1:9）>3#pond（silver carp:bighead carp=5:5）>4#pond>（silver carp:bighead carp=3:7）>2#pond（silver carp:bighead carp=7:3）.6.The growth efficiency analysis showed that the weight gain of 2#pond was the fastest,and that of 1#pond was the slowest.The growth rate of body weight of yellow catfish in experimental ponds was 2#pond>3#pond>4#pond>5#pond>1#pond,and the average body weight of yellow catfish in 2#pond was than 3#,4#,5#,and 1#ponds increased by 33.9%,38.4%,42.7%,and 45.9%respectively;The growth order of body length from large to small was 2#pond>3#pond>4#pond>5#pond>1#pond,in which,the average growth rate of body length of 2#pond was 9.6%,12.2%,13.4%,18.1%higher than that of 3#pond,4#pond,5#pond and 1#pond respectively;on the whole,on the level of body length and body weight increase of yellow catfish,it was concluded that"the growth condition of 2#pond（silver carp:bighead carp=7:3）yellow catfish was better than that of other ponds,and it was significantly better than that of other ponds."The growth status of 5#pond with the"silver carp:bighead carp"ratio of 9:1 and"silver carp:bighead carp"ratio of 1:9 was relatively poor.7.Feed energy consumption of 1#pond was the largest,feed coefficient was 1.73,feed coefficient of 2#pond was the lowest（1.04）,the order from high to low was 1#>5#>4#>3#>2#pond.From the angle of feed coefficient,the culture efficiency of Pelteobagrus fulvidraco was the highest in pond 2（silver carp:bighead carp=7:3）based on feed coefficient.Secondly,the ratio of silver carp and bighead carp was 3（silver carp:bighead carp=1:1）,and the feed coefficient of yellow catfish was the highest in pond 1（silver carp:bighead carp=9:1）,and the culture efficiency was lower.8.The main nutritional components and physiological indexes of the muscles of Pelteobagrus fulvidraco were affected by different species structure:crude protein,crude fat and crude ash content of 2#pondobagrus fulvidraco were the highest,among which the crude protein content was 16.64±0.61%.The crude protein content of yellow catfish from high to low was 2#pond>1#pond>5#pond>3#pond>4#pond.The crude protein content of yellow catfish in 2#pond was 5.5%higher than that in 5#pond,and was 6.2%higher than that in 1#pond,and was 7.8%higher than that in 3#pond,and was 7.9%higher than that in 4#pond,respectively.There was no significant difference in the physiological and biochemical indexes of yellow catfish in different proportion of"silver carp:bighead carp"（P>0.05）.