Hematological and immunological responses in the African catfish Clarias gairepinus exposed to sublethal concentrations of herbicide Ronstar®

Ecotoxicol Environ Saf. 2020 Sep 15:201:110824. doi: 10.1016/j.ecoenv.2020.110824. Epub 2020 Jun 13.

Abstract

The aim of the study was to investigate the effects of sublethal concentrations (0.3, 0.6 and 1.2 mg L-1) of the herbicide Ronstar on the hematology and some immune parameters in Clarias gariepinus juvenile (mean weight and length 58.72 ± 2.46 g and 27.60 ± 1.62 cm, respectively). The hematological and some immune parameters were studied for 21 days in a static renewal bioassay system in which the water and the herbicide were changed daily. The erythrocyte count, hemoglobin concentration (Hb), and packed cell volume (PCV) were significantly (p < 0.05) reduced in the treatment groups. When compared with the control, there were significant (p < 0.05) leucocytosis, lymphocytosis, neutropenia and monocytopenia in the treatment groups. Both the mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) were reduced ((p < 0.05) in the Ronstar-exposed fish. The result showed that the treated fish suffered hypochromic microcytic anemia. The total immunoglobulin and phagocytic indices (phagocytic capacity and phagocytic index) were significantly (p < 0.05) reduced in the treatment groups. while the respiratory burst was significantly (p < 0.05) increased in the treatment groups. The result showed that exposure to Ronstar had adverse effects on the hematology and immunocompetency of the fish.

Keywords: Anemia; Clarias; Herbicide; Leucocytosis; Phagocytosis; Respiratory burst.

MeSH terms

  • Animals
  • Catfishes* / blood
  • Catfishes* / immunology
  • Dose-Response Relationship, Drug
  • Erythrocyte Count
  • Erythrocyte Indices / drug effects
  • Erythrocytes / cytology
  • Erythrocytes / drug effects
  • Hematocrit
  • Hemoglobins / analysis
  • Herbicides / toxicity*
  • Immunoglobulins / blood*
  • Oxadiazoles / toxicity*
  • Phagocytes / cytology
  • Phagocytes / drug effects
  • Water Pollutants, Chemical / toxicity*

Substances

  • Hemoglobins
  • Herbicides
  • Immunoglobulins
  • Oxadiazoles
  • Water Pollutants, Chemical
  • oxadiazon