Assessment of the nutritive value for ruminants of poultry litter

Thirty samples of poultry litter, 14 from broiler and 16 from layer houses, were collected from poultry units in different parts of Jordan, and nutritional values were assessed. Total ash (TA) content for broiler samples (167 g/kg DM) was much lower than for layer samples (337 g/kg DM), the difference being significant at P<0.001, and the range of values, in both groups was very wide, the largest greater by about 2.75 times the smallest. Mean crude protein (CP) and acid detergent fibre (ADF) contents of broiler samples, 278 and 246 g/kg DM respectively, were greater than of the corresponding layer samples, 217 and 182 g/kg DM, and both differences were significant at P<0.01. The ranges of CP and ADF contents, of both broiler and layer samples were also large, the largest about 2.0 times the smallest. Mean copper (Cu) contents were very similar for both broiler and layer samples, at just over 50 mg/kg DM; the ranges of values of both groups were very wide, the largest around 4.0 times the smallest. Estimates of metabolisable energy (ME) were predicted from rumen fluid-pepsin in vitro digestible organic matter content of the DM (ME-IV), and organic matter loss during 72 h rumen incubation (ME-RI). The difference between means of broiler, 7.8 MJ/kg DM, and layer 7.1, for ME-IV, was not significant; the corresponding difference of ME-RI values, 7.6 and 6.4 MJ/kg DM, was different at P<0.05. The ranges within each of these means was wide, the largest about 2.0 times the smallest. Metabolisable energy contents were closely correlated with the sum of TA and ADF; the correlation coefficient for ME-IV was −0.88, and for ME-RI, −0.97. Useful estimates of ME of the litter samples could be made using regression equations for either ME-IV or ME-RI (MJ/kg DM), ME-RI being preferred for its slightly greater correlation coefficient, ME-RI (MJ/kg DM)=12.5−0.0117 (TA+ADF) (g/kg DM).