Cholinesterase activities and behavioral changes in Hypsiboas pulchellus (Anura: Hylidae) tadpoles exposed to glufosinate ammonium herbicide

PELTZER P.,; JUNGES C.M., ; ATTADEMO A.M.,,; BASSÓ A.; GRENÓN P., ; LAJMANOVICH R.C

ECOTOXICOLOGY

SPRINGER

Lugar: Berlin; Año: 2013 vol. 22: p. 1165 - 1173

0963-9292

Abstract In this study, amphibian tadpoles of Hypsiboaspulchellus were exposed to herbicide Liberty, whichcontains glufosinate ammonium (GLA), for 48 h to thefollowing concentrations: 0 (control), 3.55, 4.74, 6.32,8.43, 11.25, 15, 20, 26.6, and 35.5 mg GLA L-1. Acetylcholinesterase(AChE) and butyrylcholinesterase (BChE)activities, as well as swimming capabilities (swimmingspeed and mean distance) were measured in tadpoleswhose concentrations displayed survival rates[85 %. Ourresults reveal that sublethal concentrations of GLA significantlyinhibited both AChE and BChE activities intadpoles with respect to the control, showing a concentration-dependent inhibitory effect. The highest inhibitionpercentages of AChE (50.86 %) and BChE (53.02 %) wereregistered in tadpoles exposed to 15 mg GLA L-1. At thisconcentration, a significant increase of the swimming speedand mean distance were found in exposed tadpoles withrespect to the control, as well as a negative and significantcorrelation between swimming speed and BChE activity,thus suggesting that this enzyme inhibition is related to anincrease in swimming speed. Therefore, exposure of tadpolesto GLA in the wild at concentrations similar to thosetested here may have adverse consequences at populationlevel because neurotransmission and swimming performanceare essential for tadpole performance and survival.