How to balance a ration for growing kids
Requirements for a 66 lb doe kid gaining .23 pounds a day
|Daily DM (lb.) *||Crude Protein (lb.)||TDN (lb.)||Calcium (lb.)||Phosphorus (lb.)|
|* DM stands for||dry matter|
Step 1 Calculate the amount of hay dry matter needed to meet the crude protein requirement.
Divide lbs of crude protein required by the amount in the hay.
0.2÷ .12 = 1.7 lbs of hay dry matter
Step 2 Calculate the amount of TDN provided by the hay dry matter.
Multiply the number of pounds of dry matter needed to meet the crude protein requirement by the percent of TDN in the hay.
1.7 X .6 = 1.02 pounds of TDN
Step 3 Compare the TDN requirement of the doe kid to the amount provided by the hay.
The hay provides 1.02 lbs of TDN and the doe kid requires 1.44 lbs of TDN so the hay does not meet the requirement for the TDN. Therefore, we need to supplement with a high energy feed or in other words a grain to meet the requirement.
Step 4 Calculate the difference between the amount of TDN supplied by the hay and the amount required by the animal.
1.44 pounds required – 1.02 pounds in hay = .42 pounds needed supplemented
Step 5 Choose a feed to supplement the hay.
For this example we will use ground ear corn to make up the difference in TDN. The nutrient values of ground ear corn are listed below.
87% dry matter
9 % crude protein
Step 6 Calculate the amount of ear corn needed to meet the TDN requirement.
Divide the pounds of TDN needed by the percent of TDN in the ground ear corn to get the amount of ear corn needed to meet the TDN requirement.
.42 ÷ .83 = .5 pounds of ground ear corn
Step 7 Compare the amounts of calcium and phosphorus provided in the ration to the amounts required by the animal.
Multiply the dry matter of each feed by the percent of the nutrient found in the feed. Add the amounts of each nutrient from each feed to get the total amount of calcium or phosphorus supplied by the two feeds.
1.7 X .0027 + .5 X .0010 = .005 pound calcium
1.7 X .0034 + .5 X .0029 = .007 pound phosphorus
You will notice that the hay and corn do not meet the requirement for calcium, but are over for the phosphorus. This makes a calcium:phosphorus ratio of .7:1 which is not within an acceptable limit. In general, the ration should be between 1:1 and 2:1
Adding .01 pounds of ground limestone to the ground ear corn will increase the calcium in the ration to an acceptable level. You may also want to add some molasses to the grain mix to prevent the limestone from sifting out of the corn.
Step 8 Compare the amount of dry matter fed from the hay and the corn to the amount of dry matter required by the doe kid.
1.7 pounds hay + .5 pounds ground ear corn = 2.2 pounds of dry matter supplied by the ration. The doe kid requires 2.1 pounds of dry matter each day. This will supply adequate dry matter as well as nutrients to the doe kid.
Step 9 Convert the dry matters of each feed to the actual amounts fed.
Divide the dry matter amount of each feed by the dry matter percent in each of the feeds.
1.7÷ .89 = 1.9 pounds of hay fed each day
.5 ÷ .87 = .6 pounds of ground ear corn fed each day