the influence of bedding material and collecting period

moisture in the broiler litter should be between 12 and 25 percent (Jacob et al 1997).
Litter with moisture levels greater than 25 percent may be gummy and hard to mix
with other feeds. If the moisture content is more than 25 percent, the deep stack may
generate too much heat and the excess heat may damage (denaturate) the protein in
the litter. When protein becomes denatured, ruminants are not able to digest it as
easily. Poultry litter with moisture levels of 10 percent or less will be excessively
dusty, causing the litter to be unpalatable to ruminants. Dry litter would also not go
through a proper heat cycle during deep stacking. Too much moisture due to spillage
around bird watering systems is called "cake" and must be removed from the broiler
house. According to Jacob et al., reduced spillage will:
1. Save water,
2. Improve bird quality,
3. Improve production environment by reducing humidity and ammonia levels,
4. Reduce ammonia release from litter,
5. Reduce the volume of wet manure cake, and
6. Extend the time between litter clean-out which reduces labour and other cost.
5.3 Crude protein
According to V an Ryssen (2000) crude protein (nitrogen X 6.25) concentrations of up
to and over 30 percent on a dry basis (DM) are reported for poultry litter in the USA;
South African samples usually contain between 18 and 22 percent crude protein. This
might be due to the fact that in South Africa broiler houses are cleaned out after every
batch and in the USA only once per year. Other possible reasons might be a higher
proportion of bedding material and higher ammonia losses during sun drying. If crude
protein values are below 18 percent, the litter should be used only as a fertilizer and
not as a feed source. The crude protein consists of both true protein and non-protein
nitrogen, with uric acid the main non-protein nitrogen in poultry wastes (Noland et
al., 1955; Ruffin & McCaskey, 1998). In manure containing 68 g/kg nitrogen, 26 to
34 g/kg units consisted of uric acid and 21 g/kg units of amino acid nitrogen (Smith et
al., 1978). Other non-protein nitrogen components in manure include ammonia, urea
and creatinine.
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