title: Altered hematological and immunological parameters in silver catfish (Rhamdia quelen) following short term exposure to sublethal concentration of glyphosate.
abstract: Using agrichemicals to control unwanted species has become a necessary and common worldwide practice to improve crop production. Although most currently used agrichemicals are considered relatively safe, continuous usage contributes for soil and water contamination and collateral toxic effects on aquatic species. Few studies correlated the presence of agrichemicals on fish blood cells and natural immune system. Thus, in this study, silver catfish (Rhamdia quelen) were exposed to sublethal concentrations (10% of the LC(50-96 h)) of a glyphosate based herbicide and hematological and natural immune system parameters were evaluated. Silver catfish fingerlings exposed to glyphosate for 96 h had a significant reduction on blood erythrocytes, thrombocytes, lymphocytes and total leukocytes in contrast to a significant increase in the number of immature circulating cells. The effect of glyphosate on natural immune system was evaluated after 24h or 10 days exposure by measuring the phagocytic index of coelomic cells, and lysozyme, total peroxidase, bacteria agglutination, bactericidal activity and natural complement hemolytic activity in the serum of fingerlings. A significant reduction on phagocytic index, serum bacteria agglutination and total peroxidase was observed only after 24h exposure to glyphosate. In contrast, fingerlings exposed to glyphosate for 10 days had a significant lower serum bacteria agglutination and lysozyme activity. Glyphosate had no effect on serum bactericidal and complement natural hemolytic activity after 24h or 10 days exposure. Nonetheless, the information obtained in this study indicates that glyphosate contaminated water contributes to alter blood cells parameters and to reduce the activity of natural immune components important to mediate fish resistance to infecting microorganisms.
authors.affiliation: Faculdade de Agronomia e Medicina Veterinária, Universidade de Passo Fundo, Campus I, Bairro São José, BR 282, km 171, 99052-900 Passo Fundo, RS, Brazil. lckreutz@upf.br
authors.forename: Luiz Carlos
authors.initials: LC
authors.lastname: Kreutz
authors.forename: Leonardo José
authors.initials: LJ
authors.lastname: Gil Barcellos
authors.forename: Stella
authors.initials: S
authors.lastname: de Faria Valle
authors.forename: Tális
authors.initials: T
authors.lastname: de Oliveira Silva
authors.forename: Deniz
authors.initials: D
authors.lastname: Anziliero
authors.forename: Ezequiel
authors.initials: E
authors.lastname: Davi dos Santos
authors.forename: Mateus
authors.initials: M
authors.lastname: Pivato
authors.forename: Rafael
authors.initials: R
authors.lastname: Zanatta
mesh_terms: D000333:Aeromonas; D000818:Animals; D002397:Catfishes; D015941:Complement Hemolytic Activity Assay / Q000662:veterinary; D004305:Dose-Response Relationship, Drug; D005260:Female; D005393:Fish Diseases / Q000097:blood / Q000139:chemically induced* / Q000276:immunology; D005998:Glycine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000633:toxicity; D006540:Herbicides / Q000008:administration & dosage / Q000633:toxicity*; D008297:Male; D009113:Muramidase / Q000097:blood; D009195:Peroxidase / Q000097:blood; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D000097797:Glyphosate
chemical_list: D005998:Glycine; D006540:Herbicides; D009113:Muramidase; D009195:Peroxidase; D014874:Water Pollutants, Chemical; D000097797:Glyphosate