Yttrium oxide as an inert marker for nutrient digestibility in ferrets (Mustela putoris furo), mink (Neovison vison) and cats (Felis catus)

Apparent total tract digestibility of major nutrients and energy was determined in a comparative study with mink (n=6), ferrets (n=6) and cats (n=2) which were fed three different diets. Apparent digestibility was determined by two methods, namely quantitative faeces collection and use of yttrium oxide as an inert dietary marker. Results achieved with the two methods agreed very well, and there were no significant differences in nutrient and energy digestibility when results generated with the two methods were compared. The recovery of the marker was close to 100%, and the correlation coefficients for AD measured by the two different methods were in most cases higher than 0.9 and highly significant. It was concluded that yttrium oxide is suitable for use as inert marker in digestibility studies with carnivorous mammals.