Thermodynamic assessment of nutrition with laboratory animals

The significance of this research is gathering three different approaches under a single concept and investigation of how different parameters may affect the cellular metabolism entropy generation profiles of rodents. The first assessment includes the obese and lean rats fed with butter fat (BF) and soybean oil (SO)-based diets and the results show that obese and lean rats fed with BF diet have higher average entropy generation values than the groups fed with SO diet. Besides, the obese rats may generate 1.75 times higher lifespan entropy when fed with BF diet than fed with SO diet. On the other hand, lean rats may generate 3 times higher lifespan entropy when they fed with BF diet than fed with SO diet. The second assessment of this study considers the pregnant mouse and thermodynamic analyses show that calculated energy consumption for internal work for cellular metabolism subsystem is substantially higher than the muscle work during pregnancy. Besides that, daily entropy generation and internal work fluxes follow a highly similar phasic behaviour. Towards to end of the pregnancy external work performance decreases, and with the progress of the pregnancy second law efficiency, which follows a phasic path, increases significantly. The third system assessment in this study considers the mice under calorie (CR) and protein (PR) restriction and thermodynamic analyses show that the average daily entropy generation of cellular metabolism of CR groups increases with the increasing work output and decreases with increasing level of CR, but for the PR group, there are not any meaningful relationships for these results. Estimations show that the lifespan of the mice may increase 56-13 percent with CR and 21-7 percent with PR when compared to 24 hours ad libitum (AL) control group. The calculated cellular metabolism subsystem second law efficiency of 24 hours AL group is around 36 percent. This average value is higher than the average value of pregnant mice (21 percent). This may be related to special circumstances (being pregnant). By this study, some computational techniques are introduced where the second law concept is used for "lifespan entropy generation", "entropy generation assessment during pregnancy" and "lifespan expectancy predictions".