Page 165 - Calculating Agriculture Cover 20191124 STUDENT - A

CH 14] Calculating Agriculture 14-25

Feeding efficiency for meat animals

Feeding efficiency is the relationship of the amount of feed fed to the pounds of weight gained.

Feed fed : Weight gained

Roughly speaking beef cattle fed for slaughter will consume 8 pounds of feed for 1 pound of gain,
and will vary for the weight the animal when it is sent to market. The feed conversion for an animal
that is sent off at 800 pounds could be 6 to 1 whereas an animal that is sent off at 1100 pounds could
be 10 to 1. Pigs will consume about 4 pounds of feed for 1 pound of gain. Feeder lambs will
consume about 2 pounds of hay and 2 pounds of a grain mix for every 1 pound of gain, which gives a
ratio of 4 pounds of feed for 1 pound of gain. Broiler chickens will consume about 1.85 pounds of
feed for every pound of weight gain. Turkeys will consume about 5 pounds of feed for every pound of
weight gain.

Figure 14.10 Feed Conversions
Pounds #’s of
Specie fed gain
Beef 8 1
Swine 4 1
Sheep 4 1
Broilers 1.85 1
Turkeys 5 1

As feed efficiency, though expressed as a ratio such as pounds of feed fed to pounds of weight
gained, is fundamentally a calculation of division, or better yet, a fraction.
If an animal is fed 420 pounds of feed and gains 140 pounds in weight, then the weight to gain
ratio would be:

Feed fed : Weight gained 14

420 : 140

The division of this ratio would be:

3
140 ) 420 ——> 3 : 1 ratio or 3# feed for 1# gain.

Remember that whenever division is performed the quotient (the answer to the division) is
always the expression of the dividend (what is being divided — 420 ) in terms of the divisor (140) as
though the divisor has a value of 1. In this discussion of 420 pounds of feed fed to gain 140 pounds
of weight, the result is 3 pounds of feed fed for 1 pound of weight gain. Thus the yield ratio is:

Feed fed : weight gain
3 : 1

Example A. Howard Brown is feeding 20 pigs and they consumed a total of 840 lbs. of feed,
and they gained 280 pounds. (a) What is the pounds of feed fed per pound of gain
and (b) expressed as a ratio?

Solution algorithm:
total feed consumed
Feed consumed per l lb gain = ————————–
total gain

840 lbs consumed
Feed consumed per l lb gain = ———————-
280 lbs gain

(a) Feed consumed per l lb gain = 3 lbs of feed consumed per 1 lb gain

(b) Expressed as a ratio = 3 : 1
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