Effects of ivermectin, an antiparasitic widely used in animal production, on a main inland fisheries species

LOZANO, ISMAEL E.; PIAZZA, YANINA G.; SAGER, EMANUEL; MARINO, DAMIÁN; BABAY, PAOLA; LLAMAZARES VEGH, SABINA; DE LA TORRE, FERNANDO R.; LO NOSTRO, FABIANA

Montevideo

Encuentro; SETAC Latin America 15th Biennial Meeting; 2023

Ivermectin (IVM) is a widely used antiparasiticdrug used in animals and humans. Most of the IVM is excreted unaltered in thefeces by the treated animal being the main path of entrance into theenvironment. The sábalo Prochilodus lineatus (Valenciennes, 1836), is amigratory characiform fish present in numerous South American rivers. Thesábalo has a detritivorous diet and it is the most abundant fish resource inthe Cuenca del Plata. The extensive exploitation of livestock in the wetlandarea of the lower basin constitutes a potential risk for the fish communitiesassociated with this environment. The reproductive strategy of the sábaloinvolves the presence of larvae and juveniles in floodplain lakes of the riverswhere they coexist with the intense cattle activity on the islands, where IVMis commonly applied. In this context, the environmental impacts of theantiparasitic IVM was evaluated using a physiological, ecological andbehavioral approach in P. lineatus larvae and juveniles using experimentaldesigns in the laboratory (acute and subchronic exposures). The exposure ofjuveniles (in water and sediments) with environmental relevant concentrationsof IVM affected the biotransformation processes and promoted oxidative damagein the liver, gills and brain; and impacted swimming behavior (escape velocity,routine swimming speed, and general activity). Measurable levels of IVM weredetected in the study area. Based on the effects on swimming behavior, using avirtual population analysis, a potential impact on the sábalo population wasobserved.