Many types of research require accurate measures of body composition. In this application, we are requesting funding to purchase equipment designed to measure body composition (fat, muscle, and water). This equipment will meet the needs of thirteen National Institutes of Health- funded projects conducted by eight investigators at the Monell Chemical Senses Center. Currently, body composition is measured at Monell by chemical analysis, which is slow, or by DEXA, which is limited to mice and requires anesthetization;or we make use of nearby equipment that necessitates sacrifice of animals after measurements are taken. The advantages of the system requested in this application are that (1) it measures composition in tissue samples or in awake animals of several species (by use of animal tubes that restrict movement), (2) it is faster and more accurate than the other methods, and (3) it can measure the animals while they are onsite, without need to sacrifice them afterward. The projects that would benefit from measuring body composition involve the genetics of obesity in mice and rats;alcohol preference among selectively bred strains of mice;the interaction of taste and obesity, food intake, and body weight, especially in mice that are "sweet-liker's";the appetite for minerals such as calcium;the effect of inflammation on taste;and genetically engineered mice with compromised or enhanced taste function or with deficits in gut nutrient sensing. This requested equipment will enhance the quality of the work done by a large core group of investigators. Translational research in these areas is of critical concern because of the focus on obesity prevention and other diseases of nutrient intake, e.g., alcoholism, excess sweet intake, and diabetes. Public Health Relevance: The body composition of animals can differ because of naturally-occurring genetic variation, genetic manipulation, or other treatments, e.g., a diet high in fat or calories. The fast and accurate measurement of body composition in animals enhances the quality and reliability of experimental results. To that end, we are requesting funds to purchase a Bruker minispec LF110 system that will measure the amount of fat, muscle, and water in animal models of human disease.