Preclinical toxicity and safety evaluation of Althaea officinalis L. extract as naturopathic medicine in common carp (Cyprinus carpio L.): Hematological and biochemical study

ABSTRACT

This study was conducted to evaluate the effects of marshmallow extract (Althaea officinalis L.) administration on blood cells and biochemical parameters of carp liver. A total of 150 carps (Cyprinus carpio, initial body mass of 37.7 ± 4.4 g) were fed diets containing 0.0 (control diet), 2.5, 5, and 10 g marshmallow extract for 60 days. On days 30 and 60 of the experiment blood samples were collected and hematological parameters and liver enzyme activities—aspartate aminotransferase (AST), alanine amino transferase (ALT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP)—were measured. No significant difference was found (p > .05) in red blood cells (RBC); hemoglobin concentration (Hb); hematocrit (Htc); mean corpuscular volume (MCV); mean corpuscular hemoglobin concentration (MCH); or the percentage of neutrophils, basophils, and eosinophils in fish fed with different concentrations of marshmallow extract on days 30 and 60. However, the white blood cell (WBC) count was increased significantly in the fish fed for 60 days with feed supplemented with 5 g marshmallow extract (p < .05). The MCHC was increased signi?cantly in ?sh fed with diets supplemented with 2.5 g marshmallow extract for 60 days (p < .05). Administration of marshmallow extract (5 g) significantly increased (p < 0.05) lymphocytes on days 30 and 60. However, dietary intake of 10 g marshmallow extract had significantly decreased the monocyte percentage after 60 days. A significant increase was observed in AST, ALT, ALP, and LDH levels in livers of fish fed with extract 10 g, which may be attributed to cytotoxicity. However, marshmallow extract 2.5 and 5 g did not have adverse effects on liver enzymes. These results indicate that preclinical dietary supplementations of 2.5 and 5 g marshmallow extract per kg diet have no side effects on common carp.