Hematological and plasma biochemical parameters of the round stingray (Taeniura grabata)

Abstract

Despite the popularity of elasmobranchs housed in zoos and aquariums, there is little information regarding hematological and plasma biochemical ranges to assess their health. The main objetive of this study was to describe blood cells morphology, plus hematological and plasma biochemical parameters in the round stingray (Taeniura grabata), a species recently included in the IUCN Red List of Threatened Species. Blood samples were collected from 7 adult stingrays housed at the Poema del Mar aquarium of Las Palmas de Gran Canaria (Spain). All the leukocytes described in elasmobranchs except for neutrophils or non-eosinophilic granulocytes were observed; lymphocytes were the dominant leukocyte (52.03%), followed by heterophils or fine eosinophilic granulocyte (28.1%), eosinophils or coarse eosinophilic granulocyte (18.5%), basophils (0.53%) and monocytes (0.04%). Median blood and plasma values were 296988 cells/μL for total red blood cell count; 49100 cells/μL for total white blood cell count; 24% for packed cell volume; 0.09 mg/dL for uric acid; 3.45 g/dL for total proteins; 2.67 g/dL for globulins; 123.8 U/L for alkaline phosphatase; 6.14 U/L for amylase; 14.43 U/L for aspartate transaminase; 937.1 U/L for creatine kinase; 38.76 U/L for lipase; 527.7 U/L for lactate dehydrogenase; 14.34 mg/dL for calcium; 3.9 mg/dL for phosphorus; 105.65 mg/dL for cholesterol; 0.41 md/dL for creatinine; 40.57 mg/dL for glucose; 74.76 mcg/dL for iron; 2.02 mg/dL for magnesium; 220.21 mg/dL for triglycerides; 0.26 mg/dL for total bilirubin. The present study provides useful data which should improve our understanding of the husbandry and welfare of the round stingray