In vitro and in vivo effects of Roundup on the ovarian growth of the estuarine crab Neohelice granulata

IVANA S. CANOSA; SILVEYRA, GABRIELA R.; MAC LOUGHLIN, CAMILA; MEDESANI, DANIEL A.; RODRÍGUEZ, ENRIQUE M.

Ciudad de Buenos Aires

Congreso; 11th SETAC Latin America Biennial Meeting "The role of science in environmental decision-making"; 2015

SETAC Latinoamérica

The effect of Roundup Ultramax® (R-UP), one of the main glyphosate formulation currently used, was evaluated in vitro on ovarian pieces of the estuarine crab Neohelice granulata, during the pre-reproductive period. Small pieces were incubated for 24 h in Medium199, inside a culture chamber held at 27ºC and 5% CO2. Experimental groups comprised a control (vehicle) and three concentrations of R-UP: R-UP1 (0.0025 mg/L), R-UP2 (0.0125 mg/L) and R-UP3 (0.2 mg/L), these concentrations referring to glyphosate as active principle in the commercial formulation. Twelve females were used, each one providing biological material to every treatment (repeated measure design). Tritiated leucine was added to each 2 mL-well, in order to estimate the incorporation of this amino-acid to de novo synthesis of ovarian proteins (i.e., mainly vitellins). At the end of the assay, ovarian pieces were homogeneized, centrifugated and filtered, to finally counting the CPM in the acid precipitable fraction. A significant (p< 0.05) lower incorporation of leucine was observed in the ovarian pieces exposed to R-UP3, with respect to control. By the same time, adult females of N. granulata (N=60) were exposed for 12 wk to the same concentrations assayed in vitro. Each female was isolated in a glass recipient filled with 400 mL of artificial saline water at 12 g/L, under continuous aeration, temperature of 22ºC and photoperiod 14:10 (L:D). At the end of the assay, ovaries of all females were dissected, fixed in Bouin solution and histologically processed. For each animal, all oocyte types (pre-vitellogenic, intermediate, vitellogenic and reabsorbed) were counted in three independent section of the ovary. Statistical analysis showed a significant (p< 0.05) higher proportion of reabsorbed vitellogenic oocytes in the R-UP3 treatment, compared to control. Taken together, the results obtained both in vitro and in vivo are indicating a deleterious effect of the highest concentration of R-UP on the ovarian growth of N. granulata, also suggesting that such effect of is directly exerted on the ovary.