IRON OXIDE POTENTIAL AS A FECAL MARKER IN SHEEP

Abstract

Markers are tools to support getting information that improves animal production, especially in nutrition. The aim of this study was to evaluate doses of iron oxide as a fecal marker through its effects on fecal coloring of sheep. The experimental design was a 4 x 4 Latin square, comprising four doses of iron oxide (Fe₂O₃) addition of 0, 5, 10 and 20% of the concentrate, equivalent to 0, 7.5, 15, 30 g animal^-1, respectively. Four non-castrated male sheep were kept in adapted metabolic cages, fed a diet with proportion of forage: concentrate of   84: 16, with crushed Tifton 85 hay and the energy supplement based on ground corn. The experimental period lasted 47 days, counting 15 days for adaptation, with each subperiod comprising 7 days plus one rest. The animals received treatments with Fe₂O₃ doses mixed with the concentrate on the first day of each experimental subperiod and total feces collections were followed daily directly from the cage. There were no effects of treatments on voluntary consumption of dry matter, behavior and total feces. The color of the animals' feces was observed in all treatments after 22 h and remained under different intensities until 130 h, and the doses of 10 and 20% persisted until 154 h after supply. The Fe₂O₃ has the potential to be used as a fecal marker, becoming a tool to support in animal experimentation through its effects on the color of feces without changing the animals' behavior. The dose with 10% iron oxide in the supplement, shows greater visual persistence in the pigmentation of feces without affecting the consumption behavior.