Utilization of stored energy reserves during fasting varies by age and season in Steller sea lions

Rea, L. D.; Rosen, D. A. S.; Trites, A. W.
February 2007
Canadian Journal of Zoology;Feb2007, Vol. 85 Issue 2, p190
Academic Journal
Nine captive Steller sea lions (Eumetopias jubatus (Schreber, 1776), 1.75–6 years of age) were fasted for 7–14 d to test the effect of short-term fasting on changes in body mass and body condition. Trials were repeated during both the summer breeding season and the nonbreeding season in seven animals to elucidate whether there was a seasonal component to the ability of Steller sea lions to adapt to limited food resources. Mean percent mass loss per day was higher during the breeding season in juveniles (1.8% ± 0.2%·d–1) than in subadults (1.2% ± 0.1%·d–1), but there were no significant age-related differences during the nonbreeding season (juveniles, 1.5% ± 0.3%·d–1; subadults, 1.7% ± 0.3%·d–1). A decrease in the rate of mass loss occurred after the first 3 d of fasting only in subadults during the breeding season. Percent total body lipid ranged from 11% to 28% of total body mass at the initiation of fasting trials. Animals with lower initial percent total body lipid exhibited higher subsequent rates of mass loss and a lower percentage of tissue catabolism derived from lipid reserves. There was no evidence of metabolic adaptation to fasting in juveniles, which suggests that juvenile sea lions would be more negatively impacted by food limitation during the breeding season than would subadults.


Related Articles

  • Effects of hot-iron branding on heart rate, breathing rate and behaviour of anaesthetised Steller sea lions. Walker, K. A.; Mellish, J. E.; Weary, D. M. // Veterinary Record: Journal of the British Veterinary Association;10/1/2011, Vol. 169 Issue 14, preceding p363 

    This study assessed the heart rate, breathing rate and behavioural responses of 12 juvenile Steller sea lions during hot-iron branding under isoflurane anaesthesia. Physiological and behavioural measures were recorded in four periods: baseline (five minutes), sham branding (one minute), branding...

  • REPRODUCTIVE BEHAVIOR IN FEMALE IBERIAN RED DEER: EFFECTS OF AGGREGATION AND DISPERSION OF FOOD. Sánchez Prieto, Cristina B.; Carranza, Juan; Pulido, Fernando J.; Kie, John G. // Journal of Mammalogy;Aug2004, Vol. 85 Issue 4, p761 

    Resource dispersion influences mammalian mating systems by affecting space use by females and in turn the strategies employed by males. Other elements related to mating interactions, however, also may affect female decisions, and it usually becomes difficult to discriminate between them. Here we...

  • Grass snake.  // Encyclopedia of Animals;8/1/2017, p1 

    Grass snakes are often mistaken for poisonous adder snakes. Although they do resemble one another, there are some major differences as well. Grass snakes have yellow collars, round pupils, or dark spots in their eyes, and uneven patterns of dark markings. Adders, on the other hand, do not have...

  • Asiatic salamander.  // Encyclopedia of Animals;8/1/2017, p1 

    Asiatic salamanders are not well-known. They are an aquatic, or water-living, family which inhabits the mountain streams of central and eastern Asia.

  • Batrachuperus pinchonii.  // Encyclopedia of Animals;8/1/2017, p1 

    There is no common name for the species Batrachuperus pinchonii. This Asiatic salamander lives in the mountain streams of central and eastern Asia.

  • Seasonal variation in male-female competition, cooperation and selfish hoarding in a monogamous songbird. Steer, Jamie; Burns, KC // Behavioral Ecology & Sociobiology;May2008, Vol. 62 Issue 7, p1175 

    Both cooperation and conflict between the sexes are commonplace in monogamous mating systems. However, little is known about how cooperation and competition varies seasonally in monogamous species that maintain permanent territories. We presented territorial pairs of male and female New Zealand...

  • The cost of mating and mutual mate choice in 2 role–reversed honey locust beetles. Salehialavi, Yassaman; Fritzsche, Karoline; Arnqvist, Göran // Behavioral Ecology;Sep2011, Vol. 22 Issue 5, p1104 

    Situations where both males and females simultaneously exercise mate choice may be much more common than previously believed. Yet, experimental studies of mutual mate choice are rare as is information on the types of female traits that are favored by male mate choice. We first assessed the cost...

  • The Mating System of the Brown Hyaena, Hyaena brunnea in the Southern Kalahari. Mills, M. G. L. // Behavioral Ecology & Sociobiology;Apr1982, Vol. 10 Issue 2, p131 

    The mating system of the brown hyaena (Hyaena brunnea) in the southern Kalahari is described. Most brown hyaenas live in small mixed sex groups of related individuals. Some subadults of both sexes leave their natal groups, the females presumably to seek a vacated territory, the males to become...

  • BASES BIOLÓGICAS DEL COMPORTAMIENTO DEL ANIMAL ENFERMO. Orihuela, A.; Aguirre-Flores, V.; Vázquez-Rosales, R.; Betancourt-Alonso, M. A.; Flores-Pérez, F. I. // Universidad & Ciencia;Apr2011, Vol. 27 Issue 1, p113 

    The present study provides information on the biological bases of the behaviour of a sick animal. The physiological reactions that affect food intake, sleep periods, exploration and sexual behaviour, among other behavioural acts, are established. Some behavioural strategies of domestic animals...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics