Megan Guajardo (2007).  Thiamine concentrations in the egg yolks of bonnethead sharks (Sphyrna tiburo) and associations with fertility
Facility Advisor: Sally Spence & David Grove

ABSTRACT

Thiamine (Vitamin B1) is essential for development and survival of progeny of egg bearing vertebrates. Reductions in thiamine concentrations of egg yolk have been linked to diseases that cause low offspring survival rates in both fish and reptile populations. In this study, thiamine status of bonnethead shark (Sphyrna tiburo) egg yolk was examined to determine if thiamine deficiency is associated with the high infertility rate observed in certain Floridapopulations of this species. Thiamine concentrations of egg yolk were measured using a new, rapid solid phase extraction procedure. There were no significant differences in yolk thiamine concentrations in female sharks sampled during different stages of reproduction. Significant differences were observed in yolk of sharks from the Tampa Bay and Florida Bayestuaries, but thiamine concentrations were greater in the population with a higher rate of reproductive failure (Tampa Bay). No significant difference was observed between the infertile and fertile ova from Tampa Baysharks. These results suggest that thiamine deficiency is unlikely to be associated with infertility in S. tiburo.