DIGESTIBILITY OF CRUSTACEANS and CAPELIN IN HARP SEALS ( PHOCA GROENLANDICA )

A bstract Gross energy intake (GEI), apparent digestible efficiency (%DE), and body‐mass change were studied both in recently weaned and in subadult harp seals fed capelin ( Mallotus villosus ) and crustaceans ( Parathemisto libellula and Thysanoessa sp.) ad lib. The median %DE of Parathemisto libel...

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Bibliographic Details
Published in:Marine Mammal Science
Main Authors: Mårtensson, P.‐E., Nordøy, E. S., Blix, A. S.
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 1994
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Online Access:http://dx.doi.org/10.1111/j.1748-7692.1994.tb00486.x
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1748-7692.1994.tb00486.x
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1748-7692.1994.tb00486.x
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Summary:A bstract Gross energy intake (GEI), apparent digestible efficiency (%DE), and body‐mass change were studied both in recently weaned and in subadult harp seals fed capelin ( Mallotus villosus ) and crustaceans ( Parathemisto libellula and Thysanoessa sp.) ad lib. The median %DE of Parathemisto libellula (with a wet‐weight energy density (ED) of 3.9 kJ/g) and Thysanoessa sp. (ED: 2.3 kJ/g) was 81% and 83%, respectively, while the median %DE of capelin (ED: 8.6 kJ/g) was 94% and 93% for subadult harp seals and one harp seal pup, respectively. No correlation between age and %DE was obtained (P > 0.05). Despite ad lib. access to the food, the harp seal pups were unable to maintain body mass while on a crustacean diet, and it is therefore suggested that harp seal pups most likely must supplement their crustacean diets with fish to maintain growth.