Hematological Profile of the Juvenile Carp (Cyprinus carpio, L. 1758) Reared into a Recirculating Aquaculture System with Probiotics Supplement

Abstract

The use of probiotics in aquaculture is gained increasing scientific and commercial interest for promoting as growth supplements, mostly, but as prophylactic or therapeutic agents, too. The intensive fish rearing often are characterized by stressful conditions (overcrowd, altered water quality etc.) so, the probiotics could help by enhancing the resistance to stress. In teleostean fish, hematological indices are used as indicators of the physiological stress response to internal or external factors disturbances. Currently, there is limited information on the efficacy of the probiotics and its impact on fish blood physiology. The general aim of this paper was to assess the effect of a probiotic supplements ( BioPlus® 2B ) on hematological status in common carp ( Cyprinus carpio, Linnaeus 1758 ), cultured in a recirculating aquaculture system and fed with a commercial diet with 30% raw protein. The experiment was performed for 60 days, fish biomass being equally distributed into the 4 growth units (V1-control and three different concentrations of probiotics: V2-2,24A—10 9 CFU/kg food, V3-3,84A—10 9 CFU/kg food, V4- 7,04A—10 9 CFU/kg food ). Blood samples were drawn both at the beginning and the end of the trial period. The researches revealed a great range of variability for the hematological parameter as follows: (Hb) hemoglobin 3,40 A· 11,00 g/dl; (Ht) hematocrit 23,00 A· 41,00 %; (RBC) red blood cell count 0,72A·2,10 x 10 6 /I¼l, (MCV) mean corpuscular volume 127 A· 346,37 (I¼m3), (MCH) mean corpuscular hemoglobin 18,62 A· 59,66 (pg) and (MCHC) mean corpuscular hemoglobin concentration 12,65A·30,69 (g/dl). In the present research, these variations in the blood parameters underlined the role of the hematology in assessing the homeostatic response of fish to different technological conditions.