Development And Application Of A Noninvasive Analysis Method Of Body Composition In Mice

With the improvement of living standards,people improperly pursue high sugar,high fat and high protein diet leading to obesity.Obesity can be curbed by improving the diet.The effects of food and related components on body composition can be studied by experimental animal models.Therefore,it is higly desired to develop a fast,non-destructive and reliable method for dynamic analysis of animal body composition.In this study,low-field nuclear magnetic resonance(NMR)technique was used to develop a new method for rapid and non-destructive analysis of mouse body composition(body fluid,fat and lean meat).The low-field NMR technique combined with stoichiometric methods including Partial least squares regression(PLSR)and principal component regression(PCR)were used to establish prediction models for body fluid,fat and lean meat using the parameters from traditional methods of direct drying,Soxhlet extraction,Kjeldahl method and combustion method as a reference.The body composition of four samples predicted by these models,and it was verified by chemical method.The results showed that the correlation coefficient(R2cai)and the correlation coefficient(R2cv)of the calibration set were all greater than 0.98,and the standard error value was low,indicating that the model was stable and could accurately predict mouse body fluids,fat and lean meat content.Compared with the PLSR model,the R2 value of the PCR model was 0.68 with higher root mean square error.Therefore,the stability and accuracy of PCA were poor.The determination of the body composition of unknown mice showed that the model had good prediction effect.In order to study the effect of food components on the body composition of mice,the model of mouse obesity was established by feeding high fat diet in mice.The body composition of mice during modeling was measured by the establiesed prediction model.It was found that fat content inceased and body fluids and lean meat contents decreased with the extension of feeding time.After the mice obese model was established,the mice were treated with weight-loss diet,and the body weight prediction model was used to monitor the weight loss.The results showed that the weight loss drug could significantly reduce the fat content of the mice.Therefore,the new developed method can be used for fast,non-destructive and accurate analysis for mouse body compositions...