The amount of manure produced by feedlots in warm climates is very different than in Saskatchewan because warm and dry weather results in lower moisture content. Most references do not seem to make any mention of the use of bedding.
Table 4. United States references, as-removed manure, wet-basis.
||46 - 48
||7.2 – 9.4
|Gilbertson et al, 1975
||43 - 53
||8.9 – 12.6
|Kissinger, 2005, summer
|Kissinger, 2005, winter
|Kissinger, 2007, summer
|Kissinger, 2007, winter
[a] – Mean is presented in this table whereas a range was presented by Kissinger
American values for feedlot manure production tend to be lower than would be expected in Saskatchewan, mostly due to the difference in the use of bedding. Not only does bedding itself add mass to total manure production, it also increases the amount of moisture removed with manure.
In cold northern climates, a greater amount of bedding is used than in the warm climates. In Saskatchewan, bedding use of approximately 2 kg head-1 d-1 is common. Straw bedding may absorb 2.2 times its weight in moisture, and therefore a total of 6.4 kg of mass could result directly from the use of bedding. This is in addition to dry fecal matter excreted by the animal.
The American Society of Agricultural and Biological Engineers (ASABE) book-values predict that manure has an average moisture content of 33 per cent, and this is much lower than Saskatchewan feedlots. Average moisture content of about 50 per cent is typical in Saskatchewan (See Saskatchewan references - table 1). This difference has a significant impact on the total mass of manure removed. For example, manure production of 7.5 kg head-1 d-1 at a moisture content of 33 per cent is equivalent to 10.1 kg head-1 d-1 at a moisture content of 50 per cent.