Interpretive Summary: Adult male cats consuming diets ranging in crude protein from 85% to 160% of AAFCO recommendations have different respiratory quotients, energy expenditure, gross, digestible, metabolizable, and net energy, but not physical activity, nitrogen losses, and heat increment of feeding
By: Sanjana F Anan, Dave J Seymour, Etienne Labussière, Anna K Shoveller
The goal of this research study was to quantify net energy (NE) content of diets ranging in crude protein (CP) content from 85% and 160% of American Association of Feed Control Officials (AAFCO) model guidelines while simultaneously decreasing nitrogen-free extract (NFE) in diets fed to adult, male cats. Cats were fed diets for 14 d and physical activity was measured from day 11 for 72 h. On day 13, cats were placed within indirect calorimetry chambers to collect feces, urine and gas exchange measurements over 24 h to calculate digestible energy (DE), metabolizable energy (ME), energy expenditure (EE), respiratory quotient (RQ) and heat increment of feeding (HIF). Increasing CP in diets generally increased GE, DE, ME, and NE. EE generally increased with CP inclusion and RQ simultaneously decreased, indicating greater protein oxidation. HIF was not affected by changing CP suggesting that NE availability was affected by fecal and urinary energy losses, not by EE. NE availability increasing with CP suggests cats efficiently utilize protein as an energy source; therefore, attention should be paid to its contribution towards caloric intake within commercial diets to reduce overfeeding energy.
Read the full article in the Journal of Animal Science.
