Search

Food quality can affect many physiological characteristics in small mammals. Reproduction is a highly energy-demanding period especially for the females to produce and feed their offspring. We hypothesized that energy intake was constrained at different levels in nonreproductive and reproductive females and thus they adopted diverse energy strategies in response to diet changes. Here, we tested the effects of low fiber diet (3.5% vs. 12.4%) on energy intake and thermogenesis in nonreproductive and reproductive Brandt's voles (Lasiopodomys brandtii (Radde, 1861)), a herbivorous species. We found that the voles decreased food intake while keeping a stable digestible energy intake (DEI) in response to the low fiber diet, but DEI was increased in reproductive voles at peak lactation. Uncoupling protein 1 content in brown adipose tissue decreased in nonreproductive voles, but was stable in reproductive voles on the low fiber diet. Litter mass on day 18 of age tended to increase in the low fiber group compared with that in the control group. Our findings demonstrate that the voles have a target intake to maintain energy balance when diet composition changes and energy intake may be constrained at a high level for the reproductive voles to improve their offspring's fitness. Key words: Brandt's voles, Lasiopodomys brandtii, energy intake, leptin, low fiber diet, reproductive output. La qualite de la nourriture peut avoir une incidence sur de nombreuses caracteristiques physiologiques des petits mammiferes. La reproduction est une periode de forte demande energetique, particulierement pour les femelles, qui doivent produire et nourrir leur progeniture. Nous postulons que l'apport energetique necessaire s'etablit a differents niveaux chez les femelles non reproductrices et reproductrices, et que les femelles adoptent donc diverses strategies energetiques en reponse aux variations de leur regime alimentaire. Nous verifions les effets d'un regime pauvre en fibres (3,5 % contre 12,4 %) sur l'apport energetique et la thermogenese chez des campagnols de Brandt (Lasiopodomys brandtii (Radde, 1861)), une espece herbivore. Nous avons constate que les campagnols reduisaient leur apport alimentaire tout en maintenant un apport d'energie digestible (DEI) stable en reaction au regime pauvre en fibres, mais que le DEI augmentait chez les campagnols reproducteurs durant le maximum de lactation. La teneur en proteine decouplante 1 dans les tissus adipeux bruns diminuait chez les campagnols non reproducteurs, mais etait stable chez les campagnols reproducteurs soumis au regime pauvre en fibres. La masse de la portee au 18ejourtendaitaaugmenterdans legroupe traite au regime pauvre en fibres par rapport a celledugroupe temoin. Nous resultats demontrent que les campagnols ont un apport cible permettant de maintenir leur equilibre energetique quand la composition du regime alimentaire change et que l'apport energetique pourrait devoir etre maintenu a un niveau eleve pour permettre aux campagnols reproducteurs d'ameliorer l'aptitude de leur progeniture. [Traduit par la Redaction] Mots-cles : campagnol de Brandt, Lasiopodomys brandtii, apport energetique, leptine, regime pauvre en fibres, efficacite de la reproduction., Introduction Food quality can affect many physiological characteristics in small mammals, such as body mass, body fat content, energy metabolism, thermogenesis, and reproductive traits (McNab 1986; Bozinovic 1995). Fiber is [...]

Fish oil has been used effectively in the treatment of cardiovascular disease via triglyceride reduction and inflammation modulation. This study aimed to assess the effects of fish oil on patients with nonalcoholic fatty liver disease (NAFLD) associated with hyperlipidemia. Eighty participants with NAFLD associated with hyperlipidemia were randomly assigned to consume fish oil (n=40, 4 g/d) or corn oil capsules (n=40, 4 g/d) for 3 months in a double-blind, randomized clinical trial. Blood levels of lipids, glucose and insulin, liver enzymes, kidney parameters and cytokines at baseline and the end of the study were measured. Seventy people finished the trial. Plasma concentrations of eicosapentaenoic acid and docosahexaenoic acid significantly increased in the fish oil group after intervention. After adjustment for age, gender and BMI, fish oil significantly decreased fasting serum concentrations of total cholesterol, triglyceride, apolipoprotein B and glucose (by (mean±SD) 0.49±0.43 mmol/L, 0.58±0.89 mmol/L, 0.28±0.33 g/L and 0.76±0.56 mmol/L, respectively, P

In this study, stepwise behavioral responses of Japanese medaka (Oryzias latipes) under the joint stress of two organphosphorus pesticides (Trichlorfon and Parathion) were discussed. BEWs was used to record the data of behavior strength, to analyze behavioral response of Japanese medaka. The differences of the behavioral responses time in 20, 10, 5, land 0.1 TU were: 1.4, 4.8, 6.4, 32.2 and 43.0 h separately, which were significant. And evident difference of the behavioral responses time was not detected in different proportions of the pesticides. The results suggested that the stepwise behavioral responses of Japanese medaka were affected by both chemical concentration and exposure time. But the stepwise behavioral responses in different proportions of two organphosphorus pesticides were almost the same as each other, and the evident difference of the behavioral responses time was not detected. It proved that the toxicity effects of the joint stress of two organphosphorus pesticides on the stepwise behavioral responses of Japanese medaka were simple additivity.