Anthelmintic efficacy of Copaifera reticulata oleoresin in the control of monogeneans and haematological and histopathological effects on Colossoma macropomum

Abstract

This study investigated for the first time the anthelmintic efficacy of therapeutic baths with Copaifera reticulata oleoresin and nanoemulsion with this oleoresin against monogeneans of Colossoma macropomum, as well as the haematological and histological effects in this fish. In the therapeutic baths of three consecutives were used 100 mg/L of C. reticulata oleoresin or 250 mg/L of nanoemulsion containing C. reticulata oleoresin. Therapeutic baths with 100 mg/L of C. reticulata oleoresin had anthelmintic an efficacy of 48.5% against monogeneans (Anacanthorus spathulatus, Notozothecium janauachensis and Mymarothecium boegeri), while baths with nanoemulsion of C. reticulata oleoresin had not anthelmintic efficacy, which was discussed. Baths for 1 h with 100 mg/L of C. reticulata oleoresin or 2 h with 250 mg/L of C. reticulata nanoemulsion increased levels of plasma total protein and glucose, mean corpuscular volume (MCV) and neutrophils number in C. macropomum and decreased in the number of total leucocytes and lymphocytes. In the gills of fish exposed and controls occurred detachment of the epithelium, hyperplasia and hypertrophy, resulting in moderate fusion of the secondary lamellae. Therefore, therapeutic baths with C. reticulata oleoresin and nanoemulsion of C. reticulata oleoresin have a low toxicity to C. macropomum, as there were few changes to the blood parameters.