BELAA Manure 101 Module Exercises
The following exercises can be used in conjunction with the Manure 101 Module. Instructors may use
all exercise or use selective examples. Each exercise can be adapted for local conditions. Reference to
use of the exercises is noted on the notes page of the presentation materials.
Useful Numbers and Calculations:
Species1
Horse (1,100)
Dairy (1,400)
Beef (1,100) high energy
Swine (150)
Sheep (100)
Goat (63)
Broiler (2)
Layer (4)
Turkey (20)
lb/day
50
148
80
9.5
4
3.5
0.18
0.26
0.90
gal/day
5.98
17.7
9.5
1.2
0.4
-0.021
0.031
0.108
The number in ( ) behind the species represents the weight of the animal for the manure production volumes shown.
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Adapted from: MWPS-18 Section 1, 2000. Table 6. Daily manure production and characteristics, as excreted.
Liquid Manure Production =
Daily Manure Production x Number of Head x Number of Days Animals are present or confined
Dry Manure Production =
Daily Manure Production x Number of Head x Number of Days Animals are present or confined
Exercise 1. Manure production calculation
Liquid Swine Manure Example
You have a 1,200 head swine finishing barn. The building is occupied for 350 days a year. How many
gallons of liquid swine manure is produced?
1.2 gallons per head per day day x 1,200 head x 350 days = 504,000 gallons
Deep-bedded Beef Manure Example
You have 400 beef cows in a deep-bedded barn. The building is occupied 300 days a year. How much
manure is produced?
80 pounds per head per day x 400 head x 300 days = 9,600,000 pounds per year.
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How do you convert pounds to tons? Divide by 2,000. In this example you have
9,600,000 pounds per year divided by 2000 lbs per ton = 4,800 tons per year.
Exercise 2. How much bedding is needed for the 400 head deep-bedded beef barn in Exercise 1?
The amount of bedding used in a bedded system is highly variable can depend on number of animals,
stocking density, weather conditions, and frequency of removal. In this example we are going to add 5
pounds of bedding per head per day.
400 head x 5 pounds of bedding per day x 300 days = 600,000 pounds of bedding or 300 tons.
Extra bonus 1: If you use cornstalk bales for bedding can you calculate how many bales you will need to
meet the 300 tons?
Extra bonus 2: You could calculate the amount of manure plus bedding for total volume of manure to
be stored and calculate how much storage space you might need. Items to consider: 1) how is the
amount of manure plus bedding reduced if the storage pile composts over time? 2) What is the density
of the manure plus bedding and how does that convert for calculating storage.
Exercise 3. How much manure nitrogen is produced from the liquid swine manure example in Exercise
1?
Our manure sample results show us there is 40 lbs of nitrogen per 1,000 gallons of manure.
504,000 gallons of manure x 40lbs of N/1,000 gallons of manure = 20,160 lbs of nitrogen
Note: This is the total amount of Nitrogen produced. It does not account for losses of Nitrogen from
application (potential volatilization) or Nitrogen availability. More specific examples on how to account
for losses and availability in determining application rates are provided on Pg 7, PM 1003 Using Manure
Nutrients for Crop Production.
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