池塘混养模式下生态基对鲤生长及水质的影响

为探索池塘混养模式下生态基对鱼类生长的影响, 在6个土池中进行了一个饲养试验, 将土池分为2组, 一组为不放生态基的对照组, 另一组为放置生态基的生态基组, 每组3个重复。将尾均重为(310±11) g鲤3867尾、尾均重(810±15) g鲢及鳙370尾平均分别分为2组, 平均放养于6个土池中。对池塘鲤每天饲喂颗粒饲料3次, 饲养周期62d。在饲养期内, 每隔10天左右采集水样与底泥样品, 检测其中的浮游生物与微生物群落。在饲养结束后, 将试验鱼捕出并称重, 计算鲤的饲料效率。结果表明, 生态基组鲤鱼的增重率与饲料效率显著高于对照组; 生态基组的鲢、鳙末重显著低于对照组; 生态基组水体透明度与微生物群落多样性显著高于对照组; 生态基组浮游生物浓度低于对照组。结果表明, 在混养模式下土池中生态基的应用有利用促进鲤的生长, 然而池塘生态基的应用对于滤食性鲢、鳙的生长并无促进作用。

EFFECTS OF ARTIFICIAL SUBSTRATES ON THE CARP GROWTH PERFORMANCE AND WATER QUALITY IN PONDS EQUIPPED BY USING A POLY-CULTURE SYSTEM

To investigate the influence of artificial substrates (AS) on the growth performance of fish in pond poly-culture systems, a feeding experiment was conducted in six individual earthen ponds, which were divided into two groups. The ponds with AS in the water were labeled as the " AS group” and that without the use of AS were labeled as the " control group” (three ponds per group). A total of 3867 common carp Cyprinus carpio, (310±11) g], being artificial-feeds feeding fish, and 370 bighead carp (Aristichthys nobilis) and silver carp Hypophthalmichthys molitrix, (810±15) g], being plankton filter feeding fish, were divided into six groups and cultured in the ponds respectively. The common carp in each pond were fed with commercial particle feeds three times a day and the feeding period was 62 days. Water quality, concentration of plankton and the bacterial community presenting in the water and sediment were monitored during the experiment. At the end of the experiment, all fish were harvested and the growth of the fish and feed efficiency ratio were determined. Results showed that the weight gain rate and feed efficiency ratio of common carp in AS group was significantly higher than that of the control group. Final body weights of bighead carp and silver carp in the AS group were significantly lower than that of the controls. Water transparency and diversity indices of the bacterial community in the AS group were significantly higher than that of the control (P<0.05) and the concentration of plankton in the AS group was lower than that of the control. Results showed that the application of AS in poly-culture ponds was beneficial for the growth of common carp, being artificial-feeds feeding fish, while it was not beneficial for the growth of bighead carp and silver carp, being plankton filter feeding fish.