Trophic and maternal transfer of selenium in brown house snakes (Lamprophis fuliginosus).

Excessive concentrations of dietary Se are toxic to oviparous vertebrates (i.e., fish and birds) but little is known about its accumulation and effects in reptiles. We exposed female brown house snakes, Lamprophis fuliginosus, to 10 and 20 microg/g Se by injecting seleno-D,L-methionine into their prey items and compared the snakes to individuals receiving background levels of approximately 1 microg/g dietary Se. Snakes were fed meals equaling 25% of their body mass 2-3 times a month for 10 months. Snakes exposed to excessive Se accumulated significant concentrations of Se in kidney, liver, and ovarian tissue, but accumulation had no effect on female survival, food consumption, growth, or body condition. Fewer females exposed to excessive Se reproduced than females exposed to 1 microg/g Se (67% vs. 91%, respectively), but the reduction in reproductive activity was not statistically significant. Total reproductive output of females did not differ among the three dietary treatments. However, snakes exposed to 10 and 20 microg/g Se transferred significant concentrations of Se to their eggs. In the 20 microg/g treatment, maternal transfer resulted in Se concentrations in eggs that surpassed all suggested reproductive toxicity thresholds for birds and fish. Further studies are needed to more rigorously determine whether maternal transfer of Se in this snake species affects the viability of developing embryos or the health of offspring.