Utilisation of rations containing poultry manure as a protein source:
Poultry manure (22,5 % crude protein on dry basis) obtained from a battery operation was included in rations consisting of lucerne hay, maize meal and molasses. The control ration contained no manure. In three experimental rations, poultry manure replaced the nitrogen equivalent of lucerne hay in the control ration to an extent of 33,0, 66,0 and 1 00% resulting in rations containing 14,0, 29,0 and 47,0%poultry manure respectively. From metabolism studies conducted on 28 Merino wethers it was found that: (a) The voluntary intake of dry matter and organic matter, with the exception of the 100%replacement of the nitrogen equivalent of the lucerne hay in the control ration by poultry manure showed no statistical significant differences between the remaining rations. (b) The daily intake of gross energy decreased significantly (p< 0.01) as the percentage of manure in the ration increased from 14 to 47% No significant differences in energy intake occurred between the control ration and the ration which contained 14%manure. (c) No significant differences occurred among the various treatments for the dry matter digestibility of the rations, although the digestibility of the organic matter, crude-protein, ether extract, nitrogen-free extract, fibre as well as gross energy increased with increasing levels of poultry manure. (d) With increasing levels of poultry manure; the digestible fibre content tended to decrease and together with the higher ash content of the poultry manure rations explained most of the observed decrease in total digestible nutrient and digestible energy values of rations with an increased level of poultry manure. (e) No significant differences occurred in the nitrogen balance of wethers on any of the treatments. (f ) The results indicate that the most effective levels of poultry manure included in ration for purpose of production may lie between 14 and 29%.