Morphological features and blood parameters of Weddell seal (Leptonychotes weddellii) mothers and pups during the breeding season.

We investigated the blood status of 9 Weddell seal mothers and 9 pups during the breeding season in a field study conducted from November to December 2004 at a breeding colony in Antarctica. The blood glucose and total cholesterol concentrations were higher in the pups than in the mothers. On the other hand, the blood urea nitrogen concentration was lower in the pups than in the mothers. Growth-associated depletion of blood triglyceride was observed in the pups and may have been due to the post-weaning fast. The results characterize the blood status of Weddell seals in relation to physiological adaptations for breeding.