Genotoxicity in Caiman latirostris embryos incubated under hypoxia conditions

G.L. POLETTA, J.L. IUNGMAN, P.A. SIROSKI

Manaos, Brasil

Congreso; 20th Working Meeting of the Crocodile Specialist Group, IUCN-SSC; 2010

Crocodile Specialist Group (SSC-IUCN)

Hypoxia is known as a stressor that alter genetic machinery. Hypoxic conditions in cells have been shown to promote clastogenicity (chromosome breakage) and contribute to genetic instability. The aim of the present study was to evaluate genotoxic effects on Caiman latirostris incubated under different oxygen pressures and temperatures. A total of 48 eggs of C. latirostris from 3 different clutches were incubated under 2 temperatures (31 and 33° C) and 2 oxygen pressures (normoxia-hypoxia). Genotoxic effect was evaluated in hatchlings erythrocytes through the micronucleus (MN) test. Blood smears were done for each animal and micronucleus frequency determined by fluorescent microscope analysis. Results shown an increase in MN frequency in caimans incubated at hypoxia condition in comparison with those incubated at normoxia (p<0.05). Temperature induced no genotoxic effect (p>0.05) and no interation was observed between temperature and O2 pressure condition (p>0.05). These results demonstrated that changes in embryonic availability of oxygen induced DNA damage and may lead to alterations in different physiological functions in neonates.