Effect Of Complex Nutritional Preparation On The Water Environment,Meat Quality And Intestinal Microflora Of Crucian Crap In The Pond Cultured

The aim of these study is to explore the effect of complex nutrition preparation with Bacillus subtilis on several important physicochemical factors and plankton community structure of the water,meat quality and intestinal microorganism of the crucian crap in the aquaculture.The main results were as follow:1.To investigate the effects of complex nutrition preparation on the water environment in the pond cultured,there are two groups in this trial,group A without complex nutrition preparation,group B adding complex nutrition preparation(6g/m3),administering the complex nutrition preparation once a week,other breeding conditions are the same.The several important physicochemical factors of pond water samples were tested after 28 days,including:Dissolved oxygen(DO)、Ammonia nitrogen(NH3-N)、Nitrite nitrogen(NO2-N)、Total nitrogen(TN)and Total phosphorus(TP).Simultaneously,the number of phytoplankton and zooplankton was counted by microscope and the community structure of plankton was detected by PCR-DGGE.The results showed that DO,NH3-N,NO2-N,TN and TP in group B were higher than those in group A,and the concentrations of NO2-N and TP were significantly higher than those of group A(P<0.05).The number of phytoplankton in group B were significantly higher than that in group A(P<0.05),and the number of zooplankton was significantly higher than that of group A(P<0.01).Twenty-two bands were detected in both group A and B PCR-DGGE fingerprints of prokaryote plankton,the number of bands in group A and B were 11.67 and 14.33 respectively.The Shannon diversity index,evenness and richness of prokaryote plankton in group B were higher than those in group A.Nineteen bands were detected in both group A and B PCR-DGGE fingerprints of the water eukaryotic plankton,the number of bands in group A and B were 10.67 and 13.00 respectively.The Shannon diversity index,evenness and richness of eukaryote plankton in group B were higher than those in group A.It was suggested that the group B with complex nutrition preparation had better effect on plankton growth and community structure of plankton than group A.2.To investigate the effects of complex nutrition preparation on the meat quality and intestinal microorganism of the crucian carp,there are two groups in the trial,One thousand and five hundred healthy crucian carp,60-70g/tail weight of were raised in the group A and B respectively,group A without complex nutrition preparation,group B adding complex nutrition preparation(6g/m),other breeding conditions are the same.After 28 days,the meat samples of crucian carp in group A and group B were collected for amino acid detection and routine nutrition(Moisture,Crude protein,Crude lipid and Ash),the intestinal contents collected for viable intestinal bacteria count and intestinal microorganism detection by PCR-DGGE and Real-Time PCR.The results showed that the contents of amino acids in muscle of group B were higher than those of group A,except for glycine(Gly)and histidine(His).The contents of cysteine(Cys)and tyrosine(Tyr)in group B were significantly higher than those in group A(P<0.05).The contents of crude protein,crude fat and ash in muscle of group B were slightly higher than those in group A,while the moisture were slightly lower than that in group A.The result of viable bacteria count showed that the number of total bacteria,Bacillus,Lacticacid Bacteria and Aeromonas in the foregut of group B were significantly higher than those in group A(P<0.05),while that Escherichia coli and Photosynthetic Bacteria were significantly lower than that in Group A(P<0.05).The number of total bacteria and Escherichia coli in the midgut of group B were significantly lower than those in group A(P<0.05).The Bacillus and Lacticacid Bacteria in the hindgut of group B were significantly higher than those in group A(P<0.05),and the E.coli and Photosynthetic Bacteria were significantly lower than those in group A(P<0.05).The results of PCR-DGGE showed that 36 bands were detected by PCR-DGGE in the foregut,and the Shannon diversity index,evenness and richness of group B were higher than those of group A.A total of 30 bands were detected in the midgut by PCR-DGGE,and the Shannon diversity index,evenness and richness of group B were significantly higher than those in group A(P<0.05).A total of 39 bands were detected by PCR-DGGE in the hindgut.The Shannon diversity index and evenness in group B were higher than that in group A,the richness were significantly higher than that in group A(P<0.05).The Real-Time PCR analysis showed that the number of total bacteria of all intestinal segments in group B were significantly higher than that in group A(P<0.01).The number of Lactobacillus of foregut and midgut in group B were significantly higher than that in group A(P<0.01).The number of Enterococcus of midgut and hindgut in group B were significantly higher than that in group A(P<0.01),and the number of Enterococcus of foregut in group B were significantly higher than that in group A(P<0.05).The number of Bacteroides had no difference between group A and B in all intestinal segments(P>0.05).The results indicated that the crucian carp in group B had better meat quality,nutrient value and more complex intestinal microorganism than those in group A.