title: Evaluation of the nutrient-upgraded rodent food bar for rodent spaceflight experiments.
abstract: OBJECTIVE
  Selection of an appropriate diet for rodent spaceflight experiments is critical and may have significant effects on mission results. The National Aeronautics and Space Administration (NASA) rodent food bar (RFB) was reformulated and designated as the nutrient-upgraded RFB (NuRFB). The objectives of this study were to determine whether the NuRFB nutrient formulation meets the 1995 National Research Council (NRC) nutrient recommendations and whether the NuRFB can be used for short-term (45-d) and long-term (90-d) spaceflight experiments.
  
  
  METHODS
  Nutrient and moisture analyses of the NuRFB were performed. Young (age 13-14 wk) male Sprague-Dawley rats (n=16/group) were individually caged and fed a diet treatment consisting of 1) NuRFB, 2) RFB, or 3) modified AIN-93G containing 4% instead of the 7% fat for 45- or 90-d. At the end of the study, organs were weighted, and serum clinical chemistry indicators of organ function and hematologic measurements were determined.
  
  
  RESULTS
  Chemical analysis of the diet ingredients showed that the NuRFB met the 1995 NRC nutrient recommendations for rats. Subsequent animal feeding studies showed that NuRFB was comparable to RFB and modified AIN-93G for supporting rat growth and body weight maintenance. In addition, the safety of the NuRFB for use as a spaceflight diet was indicated by the absence of changes in organ weight or function.
  
  
  CONCLUSIONS
  Based on the study results, the NuRFB performed similarly to the RFB and met the criteria necessary for short-term and long-term rodent spaceflight experiments.
authors.affiliation: Lockheed Martin Space and Science Solutions, Moffett Field, California, USA. gwo-shing.sun-1@nasa.gov
authors.forename: Gwo-Shing
authors.initials: GS
authors.lastname: Sun
authors.forename: Janet C
authors.initials: JC
authors.lastname: Tou
authors.forename: Kurt
authors.initials: K
authors.lastname: Liittschwager
authors.forename: Anna M
authors.initials: AM
authors.lastname: Herrera
authors.forename: Esther L
authors.initials: EL
authors.lastname: Hill
authors.forename: Beverly
authors.initials: B
authors.lastname: Girten
authors.forename: Debra
authors.initials: D
authors.lastname: Reiss-Bubenheim
authors.forename: Marilyn
authors.initials: M
authors.lastname: Vasques
mesh_terms: D000465:Algorithms; D000821:Animal Feed / Q000009:adverse effects / Q000032:analysis*; D000818:Animals; D005511:Food Handling; D008297:Male; D009751:Nutritional Requirements; D009752:Nutritional Status; D009929:Organ Size; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013026:Space Flight; D013312:Stress, Physiological; D013997:Time Factors; D014481:United States; D018557:United States National Aeronautics and Space Administration; D014867:Water / Q000032:analysis; D015430:Weight Gain
chemical_list: D014867:Water