Reduction in chromium (III) oxide level as an external marker

[摘要] The objective of this study was to reduce the level of the biological marker Cr2O3 in animal diets, due to the sensibility of the sdiphenylcarbazide spectrophotometric method for chromium determination in feces, recently developed. Six levels of marker, chromium (III) oxide (0.01% - 0.02% - 0.03% - 0.05% - 0.1% and 0.2%), were incorporated into isoproteic and isoenergetic diets, for the apparent digestibility assay of the "piauçu" (Leporinus macrocephalus), in a design of entirely randomized groups. Feces were collected during sixteen days. The statistical analysis did not show significant differences in the apparent digestibility of the proteinic fraction due to the concentration levels of the marker incorporated into the diets and the collection days. Consequently, there is nothing to stop us from reducing Cr2O3 rate to at least 0.01% in these digestibility assays: spectrophotometry of sdiphenilcarbazide allows us to determine this level or even smaller levels in an accurate, simple, and quick manner.

[学科分类] 兽医学

[关键词] /font> apparent digestibiliy;chromium (III) oxide;fish;s-diphenylcarbazide    Introdução O coeficiente de digestibilidade aparente é um dos principais parâmetros para avaliar o valor nutritivo dos alimentos;sendo calculada através da diferença entre a quantidade do nutriente ingerido e da quantidade do nutriente remanescente nas excreções fecais