Etude : effet de la photoperiode sur l'activité, et l'alimentation du hamster russe

[Sandrine1308 0]

Une autre étude trouvée, datant de 2009 et très interessante également, et qui a une connexion avec l'autre étude sur le comportement agressif du male hamster russe en hiver : la période hivernale et ses courtes journées.
En résumé, l'abstract dit que les hamsters russes sont moins actifs en hiver, lorsque les périodes de jour sont courtes, ils diminuent leurs dépenses d'énergie et corrélativement mangent moins, donc maigrissent.
Cette étude a été réalisée avec des hamsters en captivité sous des conditions de lumière artificielle.
Donc, j'en déduirais, au conditionnel of course, que nos chouchous sont sujets à ce genre de modification de comportement lorsque la lumière artificielle de nos habitats ne vient pas ou prou modifier la durée de lumière du jour.

Voici l'abstract en question, toujours en anglais je sais, mais bon je n'y souis pour rrrrriennnnn.....

Effects of photoperiod on daily locomotor activity, energy expenditure, and feeding behavior in a seasonal mammal
Amy Warner, 1,2 Preeti H. Jethwa,1 Catherine A. Wyse,3 Helen I'Anson,4 John M. Brameld,2 and Francis J. P. Ebling1
Schools of 1Biomedical Sciences and
2Biosciences, University of Nottingham, Nottingham, United Kingdom;
3School of Biological Sciences, University of Aberdeen, Zoology Building, Aberdeen, United Kingdom; and
4Biology Department, Washington and Lee University, Lexington, Virginia
Corresponding author.
Address for reprint requests and other correspondence: A. Warner, Univ. of Nottingham, School of Biomedical Sciences, Queen's Medical Centre, Nottingham, UK (e-mail: mbxaw2@nottingham.ac.uk ).
Received May 19, 2009; Accepted March 3, 2010.
Copyright 2010 the American Physiological Society
Abstract
The objective of this study was to determine whether the previously observed effects of photoperiod on body weight in Siberian hamsters were due to changes in the daily patterns of locomotor activity, energy expenditure, and/or feeding behavior. Adult males were monitored through a seasonal cycle using an automated comprehensive laboratory animal monitoring system (CLAMS). Exposure to a short-day photoperiod (SD; 8:16-h light-dark cycle) induced a significant decline in body weight, and oxygen consumption ( O2), carbon dioxide production ( CO2), and heat production all decreased reaching a nadir by 16 wk of SD. Clear daily rhythms in locomotor activity, O2, and CO2 were observed at the start of the study, but these all progressively diminished after prolonged exposure to SD. Rhythms in feeding behavior were also detected initially, reflecting an increase in meal frequency but not duration during the dark phase. This rhythm was lost by 8 wk of SD exposure such that food intake was relatively constant across dark and light phases. After 18 wk in SD, hamsters were transferred to a long-day photoperiod (LD; 16:8-h light-dark cycle), which induced significant weight gain. This was associated with an increase in energy intake within 2 wk, while O2, CO2, and heat production all increased back to basal levels. Rhythmicity was reestablished within 4 wk of reexposure to long days. These results demonstrate that photoperiod impacts on body weight via complex changes in locomotor activity, energy expenditure, and feeding behavior, with a striking loss of daily rhythms during SD exposure.

[Aoko 0]

Super intéressant cette étude aussi, merci Sandrine ;)

[titan03 0]

(Bon je me répete ) Même si mon petit bonhomme est un syrien ce type de comportement correspond plus au sien, de plus je remarque qu'il mange plus qu'en milieu de mois (pas trés actif et pas trop interressait par la nourriture) et est plus actif.

[titan03 0]

Et merci de faire des recherches sur des études trés captivante et instructive

[Sandrine1308 0]

Mille merci à vous...