1. Balancing Rations
Animal Science II
Unit 8

2. Objectives Classify feeds as roughages and concentrates
Describe the six functions of a good ration
Explain the characteristics of a good ration
Balance livestock rations using commonly accepted practices

3. Classification of Feeds

4. Roughages Contain more than 18% crude fiber when dry
Includes: hay, silage, pasture, fodder
2 general class: legume roughage and non-legume roughage

5. Legume Roughages Can take nitrogen from the air
Able to due so because they have nodules on their roots that contain bacteria
These bacteria fix the nitrogen from the air in soil and make it available for the plant to use
Do so by combining the free nitrogen with other elements to form nitrogen compounds
All the clovers, alfalfa, soybeans, trefoil, lespedeza, peas and beans
Usually higher in protein than nonlegume roughages

6. Nonlegume Roughages Cannot use nitrogen from the air Lower in protein
Many common livestock feeds are nonlegume
Corn silage, sorghum silage, fodders, bluegrass, timothy, redtop, bromegrass, orchardgrass, fescue, costal Bermuda grass, common Bermuda grass, prairie grass (Western wheatgrass, Kentucky bluegrass, etc)

7. Concentrates Less than 18% crude fiber when dry Two classes
Protein supplements
Energy feeds

8. Protein Supplements 20% or more protein
Divided into 2 groups based on their source

9. Protein Supplements Animal proteins
Come from animals or animal by-products
Common: tankage, meat scraps, meat and bonemeal, fish meal, dried milk (whole & skimmed), blood meal, feather meal
Most contain more than 47% crude protein
More balanced essential amino acids
Variable quality compared to vegetable proteins
Vegetable Proteins
Come from plants
Common: soybean oil meal, cottonseed meal, linseed oil meal, peanut oil meal, corn gluten feed, brewers dried grains, distillers dried grains
Most contain less than 47% crude protein
Soybean oil meal is used most
Can supply necessary amino acids for swine and poultry
Only protein source that can be used for ruminants

10. Commercial Protein Supplements
Made by commercial feed companies
Mixes of animal and plant protein feeds
Usually made for 1 class of animal
Often mix of minerals, vitamins, antibiotics
Feed tag needs to be read and feeding directions followed

11. Energy Feeds Feeds with less than 20% crude protein Most grains
Oats, corn, sorghum, barley, rye, wheat, ground ear corn, wheat bran, wheat middling's, dried citrus pulp, dried beet pulp, dried whey
Corn is the most widely used
Followed by sorghum grain, oats, barley

12. Ration Characteristics

13. Ration Characteristics
Animals need proper nutrition to efficiently produce meat, milk, eggs, wool, work, etc
A ration is the amount of feed given to an animal to meet its needs during a twenty-four hour period
A balanced ration is one that has all the nutrients the animal needs in the right proportions and amounts
Diet refers to the ration without reference to a specific time period

14. Palatability Ration must taste good
Mold, insect and weather damage all lower palatability

15. Feed & Economics
Feed accounts for approximately 75% of the total cost of raising livestock
Therefore it is necessary to develop rations that are as economical as possible

16. Poisonous Plants Should not be included in the diet
Sometimes grow in hay fields or pastures
See Table 8-1 p.165

17. Balancing for Species and Age
Ruminants use more roughage than nonruminants
Younger animals cannot use as much roughage either
Also need to consider the purpose for which the animal is being fed
For example fattening animals generally should be fed less roughage than breeding animals

18. Micronutrients and Feed Additives
Used in small quantities
Care needs to be taken to thoroughly mix these for uniform distribution
Excessive amounts of micronutrients can be harmful

19. Functions of the Ration

20. Functions of Rations
Must be considered when determining nutrient requirements
Functions include
Maintenance
Growth
Fattening
Production
Work

21. Maintenance Primary use of nutrients is to maintain life
Animals must have energy for the functioning of the heart, breathing and other vital body processes or the basal metabolism
Energy is also needed to maintain body temperature
The ration must also provide protein, vitamins and minerals, fatty acids to replace those that are naturally lost
About ½ of the ration fed is needed for maintenance
An animal on full feed will use about 1/3 of the ration for maintenance

22. Growth
Nutrients can only be used for growth after maintenance requirements are met
Animals mature by growing
Larger species mature slower
Growth rate of large animals is faster than that of smaller animals

23. Fattening
Nutrients that are not used for maintenance or growth may be used for fattening
Fat is stored into the tissues of the body
Fat within the muscle is called marbling
Marbling makes meat juicy and good tasting
The object of fattening is to obtain the right amount of fat in the muscle without getting too much fat
Feeds that are high in carbohydrates and fats are used for fattening

24. Production
Cows, swine, horse, sheep, goats all produce milk to feed their young
Dairy goats and cows produce milk for human use as well
Chickens produce eggs
Sheep and goats produce mohair
All this production requires nutrients. The nutrients depend on the kind of production

25. Reproduction Requires proper nutrition Animals may become sterile
Extremely important for pregnant animals
Most of the fetus’s growth takes place during the last third of the pregnancy
Additional amounts of nutrients are needed during pregnancy

26. Work Horses-riding, driving
Energy needed for work comes from carbohydrates, fats, extra protein
Other needs of the body are met before nutrients are available for work
Animal will use fat stored in the body for work if the ration does not supply enough
Extra salt is also needed due to animals sweating

27. Balancing Rations

28. General Principals Must meet the nutritional needs
Nutrient allowance should be met as close as possible
Not more than 3% below the requirement

29. Dry Matter Must have a certain amount in the ration
If not the animal will be hungry
The digestive system will not function properly
Also an upper limit that varies with the animal being fed and its size
Total dry matter in the ration of a full fed animal should not be more than 3% above its need

30. Protein Measured by the total protein (TP) need of the animal
Digestible protein may also be used to balance the ration
Essential amino acids must be included when balancing a ration for nonruminants
Acceptable to allow 5-10% more protein in the ration than the animal needs

31. Energy Four methods of measurement
Digestible Energy (DE)
Total Digestible Energy (TDE)
Metabolizable Energy (ME)
Net Energy (NE)
Gross energy of feed is measured in a lab using a bomb calorimeter
The feed is burned completely and the total amount of heat released from the burning is the gross energy

32. Digestible Energy
The gross energy of the feed minus the energy remaining in the feces of the animal after the feed is digested

33. Metabolizable Energy For Ruminants For Non Ruminants
The gross energy in the feed minus the energy found in the feces, gaseous products of digestion and urine
For Non Ruminants
The gross energy in the feed minus the energy found in the feces and urine

34. Net Energy Metabolizable energy minus the heat increment
Energy used for
Maintenance only NEm
Amount of energy used to keep the animal’s energy in equilibrium-there is no net gain or loss of energy in the animal’s body tissues
Maintenance plus production NEm+p
Production only NEp
Amount of energy need above the amount used for maintenance that is used for work, tissue growth, fat production, fetus growth, or milk, egg, or wool production and so on

35. Total Digestible Nutrients (TDN)
Total of the digestible protein, digestible nitrogen-free extract, digestible crude fiber and 2.25 X’s the digestible fat
Gives a measure of the total energy value of the feed when it is fed
Varies with the class of animal to which it is fed
Should not be more than about 5% more than what the animal needs

36. Balancing Calcium and Phosphorus
Important in balancing rations
Should be between a 1:1 and 2:1 ratio
The ratio is more important than the total amount being fed
Total Ca and P are often more than needed when other requirements are met
Other mineral needs are usually not considered and can be met with trace-mineralized salt

37. Vitamins Vitamin A is taken into account when balancing the ration
Other vitamin needs are added with out calculating the vitamin content of the feed
Vitamin A will often be more than needed but is not harmful
Vitamin deficiencies can occur in cattle and sheep during pregnancy if low quality legume hay is fed
Vitamin supplements should always be added to pregnancy rations

38. Getting the Most Bang for Your Buck
Some feeds are cheaper sources of nutrients than others
Energy feeds should be compared based on the price per pound of energy (TDN, DE, ME or NE)
Protein feeds should be compared in terms of price per pound of total protein or digestible protein
The least expensive source of nutrients should be used as much as possible

39. Relationship Between 100% Dry Matter Basis and As-Fed Basis
All feed contains some moisture and the amount varies with the feed, form of feed, stage of growth at harvest, length of time in storage, storage conditions
The appendix in the back of the book shows the average percent dry matter in the feeds listed

40. 100% Dry Matter Basis
Data presented is calculated on the basis that all moisture has been removed

41. As-Fed Basis
Data is calculated on the basis of the average amount of moisture found in the feed as it is used on the farm

42. Rules of Thumb for Balancing Rations

43. Beef
See p in text

44. Swine
See p. 173 in text

45. Sheep
See p. 173 in text

46. Goats
See p. 173 in text

47. Horses
See p & Table 8-2

48. Poultry
See p. 174 in text

49. Steps in Balancing a Ration

50. Step 1
Identify the kind, age, weight and function of the animal(s) for which the ration is being formulated.
In our text suggested rations and feeding programs are found in the units on the specific species; these may be used for formulating rations.

51. Step 2
Consult the table of nutrients to determine the nutrient need(s) of the animal(s)
These requirements are called FEEDING STANDARDS
Based on average requirements
May not meet the needs under specific conditions
Adjustments may be needed if unusual conditions exsists

52. Step 3 Choose the feeds to be used
Consult the feed composition table to determine the nutrient content of the selected feed
Nutrient contents differ with species

53. Step 4 Calculate the amount of each feed to be used in the ration
Sevral methods are available to do this but we will use the Pearson Square Method

54. Step 5 Check the ration formulated against the needs of the animal(s)
If there is/are excessive amount(s) of a nutrient(s) present it may be necessary to reformulate the ration

55. Determining Ration Costs
Check the ration cost to see if it is the most economical
Calculate cost per pound or per ton
Daily cost of feeding may also be calculated if a daily consumption rate is know

56. Pearson Square 45

57. The Pearson Square Cannot balance rations by trial and error
Pearson Square simplifies balancing rations
Can only use two feeds

58. Using the Pearson Square
EXAMPLE
2,000 pounds of feed is needed to feed a 100-pound growing hog. A feeding standards table shows that a 14% crude protein ration is needed. Corn and Soybean oil meal (SBOM) are selected as feeds. A feed composition table shows that corn has 8.9% and SBOM has 45.8% crude protein on an as-fed basis. How much corn and soybean oil meal need to be mixed together for 2,000 pounds of feed?

59. STEP 1 Draw a square with lines connecting the opposite corners.
Write the percent of crude protein (14) in the center of the square. 14

60. STEP 2
Write the feeds to be used and their crude protein percents at the left hand corners of the square.
Corn 8.9 14
Soybean
oil meal 45.8

61. STEP 3
Subtract the smaller number from the larger, along the diagonal lines. Write the differences at the opposite end of the diagonals.
31.8=
Corn 8.9 14
Soybean
oil meal 45.8
5.1=14-8.9

62. STEP 3
The difference between the percent protein in the soybean oil meal and the percent protein in the ration are the parts of corn needed.
The difference between the percent protein in the corn and the percent protein in the ration are the parts of soybean oil meal neeeded.
The sum of the numbers on the right equals the difference in the numbers on the left. This fact is used as a check to see if the square is set up correctly.

63. STEP 3 14 36.9 36.9 Parts Corn 31.8 Corn 8.9 Soybean oil meal 45.8
5.1
Parts SBOM
36.9
36.9

64. STEP 4
Divide the parts of each feed by the total parts to find the percent of each feed in the ration
Corn 31.8/36.9x100=86.2%
Soybean oil meal 5.1/36.9x100=13.8%

65. STEP 5
It is known that 2,000 pounds of the mixture is needed. To find the pounds of each feed in the mix, the percent of each feed is multiplied by the total pounds of the mix
Corn 2,000 x 0.862= 1,724 pounds
SBOM 2,000 x 0.138= 276 pounds
*Numbers have been rounded to full pounds.

66. STEP 6
Check the mix to ensure that the protein need is met. Multiply the pounds of the feed in the it’s precent protein .
Corn 1,724 x 0.089= 153 lbs of Corn
SBOM 276 x 0.458= 126 lbs of SBOM
Add the pounds of protein together
= 279
Divide by the total weight of the mix
279/2,000 x 100= 14%
The mix is balanced for crude protein content!

67. Using the Pearson Square to Mix Two Grains with a Supplement (START)
Can be used to find out how much of two grains should be mixed with a supplement
Proportions of grain must be known first

68. EXAMPLE
2,000 pound mix of corn, oats and soybean oil meal is needed. The mix is to contain 16% Digestible Protein. A decision is made to use ¾ corn and ¼ oats in the mix. Thus, the proportion of corn to oats is 3:1. How many pounds of corn, oats and soybean oil meal are needed?

69. STEP 1
Need to find the weighted average percent of protein in the corn and oats first.
To do this
Multiply the proportion of corn (3) by the percent digestible protein in corn (7.1). Do the same for oats. Then add the two answers together and divide by the total parts (4). This answer is the weighted average percentage of digestible protein in the corn oats mix.

70. STEP 1 cont… 3 x 7.1=21.3 (Corn) 1 x 9.9= 9.9 (Oats) 31.2
31.2/4= 7.8% Digestible Protein in the corn-oats mix

71. Using the Pearson Square X
Used in the same method as before to mix two feeds.
On a sheet of paper, work out this problem
3 parts Corn, 1 part oats 7.8 16
Soybean oil meal 41.7

72. Using the Pearson Square
Same method can be used for mixing two protein supplements and 1 grain
Can also be used to mix 2 grains and 2 protein supplements
Just remember that the proportions of like feed must be decided upon before hand and the weighted average percent of protein found
Any measure of nutrients in the feed may be used
Energy- TDN, NE, ME, DE
Protein- CP, DP

73. Balancing A Swine Ration
See p in Text

74. Balancing a Ration for Beef
See p in Text

75. Using Algebraic Equation to Balance Ration
May be used instead of Pearson Square
Basic equations are
X= pounds of grain needed
Y= pounds of supplement
Equation #1
X+Y= Total Pounds of Mix Needed
Equation # 2
(% Nutrient in grain) x (X) + (% Nutrient in Supplement) x (Y)= pounds of nutrient desired in mix

76. EXAMPLE Same problem as the 1st Pearson Square Example
Mix of 2,000 lbs is to be balanced for protein using two feeds.

77. EXAMPLE cont… Place the desired values in equation 2 0.089X+0.458Y=280
REMEMBER TO EXPRESS % AS DECIMALS
0.089X+0.458Y=280
280 is found by multiplying the quantity of feed (2,000 lbs) by the percent (14) [or the amount] of nutrient desired: 2,000x0.14)

78. EXAMPLE cont…
Either X or Y must be canceled by the multiplication of equation 1 by the percentage of nutrients for either X or Y, and the resulting equation 3 is subtracted from equation 2. This example uses the percentage crude protein for corn (0.089), giving equation 3
0.089X+0.089Y=178 (178 is found by multiplying times 2,000 lbs)

79. EXAMPLE cont… SUBTRACT equation 3 from equation 2
0.089X+0.458Y=280
-0.089X-0.089Y= -178
0.369Y=102
Y= 276 lbs soybean meal
X may then be found by substituting the value of Y in equation 1 and solving
X+276=2,000
X=2,
X= 1,724 lbs of corn

80. Algebraic Equations Get the same result as Pearson square
May be used to balance rations using 3 or more feeds
Same initial step must be taken as when using the Pearson Square—group similar feeds into two groups and determine the proportions of each to be used in each group
After this is done the same procedure as above is followed.