Lamb-feeding rations

              lf)o.lOOS      NEW MEXICO COLLEGE OF AGRICULTURE AND MECHAltfC^Ts'^'''-^1^
AND AGRICULTURAL EXPERIMENT STATION t%£v
Press Bulletin 1009 \ 21 i'-~
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LAMB-FEEDING RATIONS ♦^ L f a „ „  -. V
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Most lamb feeders when selecting rations for fattening lambs want to' know the
following facts:
1. The best combination of available feeds.
2* The amount of each feed that a lamb requires each day.
3. The total amount of feed required for fattening.
A. The average daily gain.
5. Cost of 1 pound of gain.
Answers to these questions may be found from the results of tests conducted at
the New Mexico Agricultural Experiment Station to determine the effectiveness of 67
feed combinations for fattening New Mexico range lambs. The combination of feeds in
each ration, the amount that should be fed each day, the amount of each ration
necessary for 1 pound of gain, and the gain in lamb weight each day are given in
tabular form.
The total amount of feed required and the cost of a pound of gain can be
calculated from the rations as follows: If a fat lamb is" to weigh between 90 and
100 pounds (a desirable slaughter weight) on a midwestern or California market, it
should weigh 95 to 108 pounds in the feed lot. The difference between this finished weight of 95 to 108 pounds and the weight of the feeder lamb when started on feed
is the number of pounds that are to be gained in the feed lot. For example, if the
feeder lamb weighs 70 pounds when put in the feed lot, it will need to gain about
30 pounds to have a 100-pound weight when shipped from the feed lot. If the average
daily gain is .3 pound, a 100-day feeding period will be necessary. The feeder,
therefore, can determine the necessary pounds of gain from his feeder lamb weight,
select the ration he is going to feed, get the rate of daily gain stated for that
ration, and from these two facts calculate the number of days he will need to feed.
If he wants to determine the total feed required to fatten a lamb when a
certain ration is used, he can multiply the amount of each feed needed for 1 pound
of gain by the required nuaber of pounds as calculated above. Knowing the pounds
of feed necessary for 1 pound of gain is useful in determining relative costs of
different rations. This can be done by applying local feed prices to the required
amounts of feed.
In selecting a ration, the feeder must always keep in mind that a certain ;,iini-
mum rate of gain is necessary, b-low which fattening will not be fast enough to
properly condition the lamb for slaughter, regardless of the number of days fed.
In these rations, a gain of less than .23 pound per day may be considered the minimum gain for proper fattening.
All feed requirements and rates of daily gain given in the tables are based
on feedlot weights and are higher than those based on buying weights and selling
weights at the market. This does not make them any less reliable as guides for the
feeder, but he must understand the basis of calculation so that he will not think
the rates of gain as given are too high and therefore try to fatten lambs by using
rations giving the same rates of gain as he has had when he h-is used buying and
market selling weights to calculate average daily rate of gain.
Due to the considerable variations in quality of the sane feeds, difference in
feeder lambs, and difference in ability of different feeders, the rations may vary
in fattening power as much as .04 pound in average daily gain.