HAEMATOLOGICAL AND SERUM BIOCHEMICAL CHANGES ASSOCIATED WITH BACTERIOLOGICAL INFECTION IN ACIPENSER GUELDENSTAEDTII REARED IN INTENSIVE CONDITION

Angelica Docan, Iulia Grecu, Mirela Creţu, Alina Antache, Lorena Dediu

Abstract
   Bacterial diseases are among the most important causes of economic losses in cultured fish species. The haematological parameters are an important tool of diagnosis that reveals the state of health of fish species. This study evaluated the haematological changes in Acipenser gueldenstaedtii under effect of the influence of pathogenic bacteria compared to healthy specimens and those treated. Infected specimens of sturgeon reared in recirculating aquaculture system had individual weights of 270 ± 0,08g, 320 ± 0,098 g/ex for treated fish and respectively 450± 0,11 g/ex for healthy specimens. 5 ml of blood was sampling from each fish by caudal venous puncture. Blood was analysed with routine method used in fish haematology. Was determined the following haematological and serum biochemical parameters: plasma glucose (mg/dl) and protein (g/dL), red blood cell counts (RBCc, x 10⁶/µl), the haematocrit (PCV, %) and haemoglobin concentrations (gl/dl). Using standard formulas the red blood indices were computed: the mean corpuscular volume (MCV), the mean corpuscular haemoglobin (MCH) and the mean corpuscular haemoglobin concentration (MCHC). Differences in haematological parameters were statistically analyzed by ANOVA test. Physiological stress, induced by the action of pathogenic bacteria was reflected in the haematological indices: RBC count 0.27 x 10⁶cel./mm³ for infected fish, 0.32 x 10⁶cel./mm³ for treated fish and 0.45 x 10⁶cel./mm³ for healthy fish, haemoglobin concentration 4.31, 4.90 and 5.82 g/dl, haematocrit concentration 9, 13 and 15 %, MCV 370.9, 457.2 and 347.29 fL, MCH 172.55, 167.81 and 136.43 pg, MCHC 47.88, 36.89 and 39.72 g/dl. Plasma glucose values recorded 82.9 mg/dL for infected fish, 93.06 mg/dl for treated fish and 91.82 mg/dL for healthy fish. Plasma protein value was 2.56 g/dL for infected fish, 3.19 g/dl for treated fish, respectively 3.37 g/dL for healthy fish.

Key words: sturgeon, pathogenic bacteria,haematological indices, plasma glucose and protein