Broiler litter as a source of selenium for sheep

Abstract

Two trials were conducted to establish whether selenium (Se) present in broiler litter is available to sheep consuming the litter. In both trials the treatments were pure broiler litter or litter mixed with 7.5% or 15% of molasses. The first trial was a partial digestion study using litter containing 1.0 mg Se/kg dry matter (DM). The double marker technique was used to follow Se flow through the digestive tract with ytterbium as solid phase marker and chromium as liquid phase marker. Between 28% and 53% of dietary Se disappeared between the abomasum and ileum and between 2% and 28% between the ileum and the faeces. None of the differences between treatments were statistically significant. The apparent digestibility of Se in the broiler litter was 52%, 47% and 52% for the 100%, 92.5% and 85% litter treatments, respectively. In the second trial individually fed sheep received the experimental diets for 83 days. The broiler litter contained 0.68 mg Se/kg DM. Selenium concentrations in blood and plasma increased with time. At slaughter, Se concentrations were measured in the livers, kidney cortices and cardiac muscles. Although the sheep consumed more ( P < 0.05) of the diet, thus Se when molasses was added, Se concentrations in the tissues did not differ among treatments. The livers contained 3.1, 2.2 and 2.3 mg Se/kg DM, kidneys cortices 7.2, 9.0 and 8.3 mg Se/kg DM and the cardiac muscles 1.35, 1.42 and 1.6 mg Se/kg DM in the 100%, 92.5% and 85% litter groups, respectively. It was concluded that the Se in the broiler litter was readily available to sheep.