Effect of synbiotic dietary supplementation on growth, physiological and immunological parameters in common carp (Cyprinus carpio L.) fingerlings and on yield and physiological parameters in lettuce (Lactuca sativa L.), cultivated in mesocosmos aquaponic system

MIROSLAVA KAYMAKANOVA, KATYA VELICHKOVA, YORDAN STAYKOV, DESISLAVA SLAVCHEVA-SIRAKOVA, STEFKA STOYANOVA, IVAYLO SIRAKOV, RAYNA ATANASOVA

Abstract: The aim of the present research was to test the effect of commercial synbiotic (Bio balance®) on growth, physiological and immunological parameters in common carp fingerlings (Cyprinus carpio L.) and on plant productivity and physiological parameters in lettuce (Lactuca sativa L.) cultivated in mesocosmos aquaponic system. The current study demonstrated for first time that the application of synbiotic as feed supplementation in extruded pellet for carp in aquaponics recirculation system could be successful. The positive effect of Bio balance® on growth rate and feed utilization in carp fingerlings cultivated in aquaponic mesocosmos was observed and average final weight and FCR in fish fed with feed supplemented with Bio balance® were higher with 9.8% and 26.1% respectively, compared to the values of these parameters for fingerlings received feed without addition of synbiotic (P≤0.05). The bactericide and phagocytosis activities and hemoglobin content in blood of carps were higher in fish from the experimental variant (S1), compared with the values of these parameters found in fingerlings from the control variant (S0), but the differences were not significant (P≥0.05). The lettuces from S1 showed 2.14% higher fresh weight compared to that of lettuces from S0, but the difference was not significant (P≥0.05). The better yield in lettuce from experimental variant S1 where the carp feed was supplemented with synbiotic probably was result from better pH in water and the connected with this better assimilation of nutrients from the salad from S0 variant. Fingerlings diet supplemented with Bio balance® stimulates the physiological proceses in the experimental plants. The positive effect of the synbiotics is reflected by improved leaf gas exchange parameters and nitrate reductase activity in lettuce.

Keywords: aquaponics; common carp; growth; immunity; lettuce; photosynthesis; physiology; symbiotic

Date published: 2018-04-27