Integument in Antarctic seals: A comparative study and its relation to extreme environments

KRMPOTIC, CECILIA MARIANA; LOZA, CLEOPATRA MARA; NEGRETE, JAVIER; SCARANO, ALEJO CARLOS; CARLINI, ALFREDO ARMANDO; GUERRERO, ALICIA; BARBEITO, CLAUDIO GUSTAVO

ACTA ZOOLOGICA

WILEY-BLACKWELL PUBLISHING, INC

Año: 2017

0001-7272

Due to the semi-aquaticlifestyle of seals and the extreme climates they inhabit, theirintegumentary system has aroused the curiosity of several authors for more than acentury. The aim of this contribution was to perform an exhaustive histological descriptionof the integument Antarctic seals through different methodological approachesin a comparative framework. The species considered include theice-obligate?Weddell (Leptonychotes weddellii) and leopard (Hydrurga leptonyx)seal?and the ice-tolerant,and southern elephant seal (Mirounga leonina). In addition,we attempted to link the histological features to their different lifestyles. Allthree species showed features related to their amphibious lifestyle (i.e., parakeratoticepidermis with abundant melanin granules, dermis with numerous arteriovenousanastomoses and a great amount of elastic fibres). In aquatic mammals, parakeratosiswould decrease cellular replacement, the great amount of melanin is related to thehigh exposure to solar radiation, the presence of arteriovenous anastomoses is relatedto thermoregulatory mechanisms, and the presence of elastic fibres is due to variationsof thickness in the adipose tissue that requires high elasticity of the dermis.