z-logo
open-access-imgOpen Access
Lung function assessment in the Pacific walrus (Odobenus rosmarus divergens) while resting on land and submerged in water
Author(s) -
Alicia BorqueEspinosa,
Diana FerreroFernández,
Romana Capaccioni-Azzati,
Andreas Fahlman
Publication year - 2020
Publication title -
journal of experimental biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.367
H-Index - 185
eISSN - 1477-9145
pISSN - 0022-0949
DOI - 10.1242/jeb.227389
Subject(s) - tidal volume , expiration , respiratory system , lung , spirometry , lung volumes , sitting , lung function , respiratory physiology , ventilation (architecture) , medicine , pulmonary compliance , anesthesia , physics , pathology , meteorology , asthma
In the present study, we examined lung function in healthy resting adult (born in 2003) Pacific walruses (Odobenus rosmarus divergens) by measuring respiratory flow (V̇) using a custom-made pneumotachometer. Three female walruses (670 – 1025 kg) voluntarily participated in spirometry trials while spontaneously breathing on land (sitting and lying down in sternal recumbency) and floating in water. While sitting, two walruses performed active respiratory efforts, and one animal participated in lung compliance measurements. For spontaneous breaths, V̇ was lower when lying down (e.g. expiration: 7.1±1.2 l · s−1) as compared to when in water (9.9±1.4 l · s−1), while tidal volume (VT, 11.5±4.6 l), breath duration (4.6±1.4 s), and respiratory frequency (7.6±2.2 breaths · min−1) remained the same. The measured VT and specific dynamic lung compliance (0.32±0.07 cmH2O−1) for spontaneous breaths, were higher than those estimated for similarly sized terrestrial mammals. The VT increased with body mass (allometric mass-exponent=1.29) and ranged from 3 to 43% of the estimated total lung capacity (TLCest) for spontaneous breaths. When normalized for TLCest, the maximal expiratory V̇ (V̇exp) was higher than that estimated in phocids, but lower than that reported in cetaceans and the California sea lion. The V̇exp was maintained over all lung volumes during spontaneous and active respiratory manoeuvres. We conclude that location (water or land) affects lung function in the walrus and should be considered when studying respiratory physiology in semi-aquatic marine mammals.

The content you want is available to Zendy users.

Already have an account? Click here to sign in.
Having issues? You can contact us here