Effects of Glyphosate and Polyoxyethylene Amine on Metabolic Rate and Energy Reserves of Procambarus clarkii Juveniles

P. clarkii juvenile crayfish were exposed during 60 days to sublethal concentrations of glyphosate (G), polyoxyehtylene amine (P) or a combination of both (G+P), together with a control group of aged tap water (C). At the end of the experiment, the following statistical differences were noted, with respect to control: 1) a lower metabolic rate in both G and G+P groups, 2) a higher glycemia in G group with no differences in hemolymphatic lactate levels, 3) a lower muscle glycogen levels in both P and G+P groups, 4) a lower level of protein muscle in the P group. Taken together, these results suggest that glyphosate may cause a metabolic arrest. Additionally, under chronic exposure conditions, polyoxyehtylene amine acts as a strong stressor, leading to the utilization of both muscle carbohydrate and protein reserves.