絮团浓度对革胡子鲇零换水养殖效果的影响  

Effect of flocs concentration on the performance of African catfish(Clarias gariepinus)in bioflocs aquaculture systems

作　　者：陈晓庆[1] 张扬 谭竟宏 罗国芝[1,2,3] 谭洪新[1,2,3] CHEN Xiaoqing;ZHANG Yang;TAN Jinghong;LUO Guozhi;TAN Hongxin(Shanghai Aquaculture Engineering Technology Research Center,Shanghai Ocean University,Shanghai 201306,China;Key Laboratory of Freshwater Aquatic Germplasm Resources,Ministry of Agriculture and Rural Affairs Shanghai Ocean University,Shanghai 201306,China;International Experimental Teaching Demonstration Center for Aquatic Science,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]上海海洋大学,上海水产养殖工程技术研究中心,上海201306 [2]上海海洋大学,农业农村部淡水水产种质资源重点实验室,上海201306 [3]上海海洋大学,水产科学国际级实验教学示范中心,上海201306

出　　处：《中国水产科学》2020年第7期779-788,共10页Journal of Fishery Sciences of China

基　　金：国家自然科学基金项目(31202033).

摘　　要：为研究絮团浓度对革胡子鲇零换水养殖效果的影响,在不额外添加有机碳源(只利用饲料中的碳)的革胡子鲇(Clarias gariepinus)养殖系统中,设置了平均絮团质量浓度为561.18 mg/L和780.41 mg/L两个处理组,比较了两实验组的水质、菌群结构、鱼生长及氮利用效率。结果表明,两种浓度絮团条件下,总氨氮(total ammonia nitrogen,TAN)和亚硝酸氮(NO2–-N)能分别维持1.84 mg/L和1.79 mg/L以下。两处理组间pH、溶解氧(dissolved oxygen, DO)、TAN、NO2–-N、氮素利用效率及主要生长指标无显著差异(P>0.05),但高浓度絮团组中的硝酸氮(NO3–-N)浓度(822.0 mg/L)明显高于低浓度絮团组(623.33 mg/L)。高通量测序分析菌群结构结果表明,两组间门水平的菌群组成种类及优势度无显著性差异(P>0.05),属水平的菌群种类及优势度差异显著(P<0.05)。两处理组中的革胡子鲇存活率分别达到(91.11±1.53)%和(94.44±2.08)%,饲料系数为(1.41±0.18)和(1.27±0.26),特殊生长率为(2.13±0.04)%/d和(2.19±0.08)%/d,均无显著差异(P>0.05)。两实验组饲料氮的利用率分别达到了72.17%和71.34%。综合以上结果认为,仅利用饲料中的碳既能维持革胡子鲇的零换水养殖且能取得较高的氮素利用效率,两种絮团浓度对革胡子鲇的生长无显著影响,高浓度絮团组中的硝化作用更明显。In aquaculture systems,a lack of water exchange,continuous input of food,and bacterial growth in culture tanks,can cause an increase in floc concentrations.Increased floc concentrations increase oxygen demand and clog the gills of cultured animals.Therefore,floc concentration is one of the most important management factors in a floc aquaculture system.The African catfish(Clarias gariepinus)is a candidate for biofloc aquaculture systems due to the ability to adapt to the adverse water conditions.No previous studies have investigated the effects of floc concentrations on African catfish cultured in biofloc aquaculture systems.The current study investigated the effect of different floc concentrations on the water quality,bacteria community compositions,nitrogen budget,and growth performance of juvenile African catfish in biofloc systems for 140 d.Two treatments were referred as low floc concentration(LF)or high floc concentration(HF),with an average concentration of 561.18 mg/L and 780.41 mg/L,respectively.The results suggested that there were no significant differences in average concentrations of total ammonia nitrogen(TAN),nitrite nitrogen(NO2–-N),growth performance of the farmed fish,and nitrogen budget items between the treatments(P>0.05).Nitrate nitrogen(NO3–-N)in HF(822.0 mg/L)was significantly higher than that of LF(623.33 mg/L),which suggested that the nitrification process was ongoing in the current aquaculture systems.BFT aquaculture systems always have high biomass,including cultured fish and microorganisms aggregated in bioflocs.The relative abundance of the top five phyla of bacteria did not differ significantly between the treatments(P>0.05),however,a significant difference was observed at the genus level(P<0.05).African catfish survival rates ranged from(91.11±1.53)%in LF,and(94.44±2.08)%in HF treatments.The food conversion ratio was(1.41±0.18)for LF and(1.27±0.26)for HF,and the specific growth rates were(2.13±0.04)%/d and(2.19±0.08)%/d,respectively.The efficiency of nitrogen use in food wa

关 键 词：生物絮团养殖 絮团浓度 革胡子鲇 零换水 

分 类 号：S96[农业科学—水产养殖]