1. Ruminant Animal Feed Management Issues and Practices
Speaker Notes:
The purpose of this session is to give an overview of feed management issues with dairy and beef cattle production and basic nutrition and feed management practices that effect nutrient excretion.
Required Course Materials:
Supplemental Resources:
NRC Nutrient Requirements of Beef Cattle. Revised Edition. National Research Council. National Academy of Sciences. National Academy Press. Washington, DC
NRC Nutrient Requirements of Dairy Cattle. Revised Edition. National Research Council. National Academy of Sciences. National Academy Press. Washington, DC
LPES Lessons 12 and 13. Feeding dairy cows to reduce nutrient excretion, and Using dietary strategies to reduce the nutrient excretion of feedlot cattle, respectively.
Suggested Learning Exercise:
Non-ruminant animal feed management issues exercise page 47-48
CNMP Core Curriculum
Feed Management – Section 6.2
CNMP Core Curriculum

2. Core Training Curriculum
CNMP Development
Core Training Curriculum
These course materials have been developed as a cooperative effort between five land-grant universities and The Natural Resources Conservation Service.
Copyright Information
Ames, Iowa 50011, (515)
Copyright © , Iowa State University of Science and Technology. All rights reserved.

3. Objectives Diet composition for ruminants
Review digestion processes and excretion of N and P of the ruminant
Discuss aspects of ration balancing
Discuss reasons for overfeeding of nutrients
Provide strategies for reducing nutrient excretion
Speaker Notes:
List the objectives of this session.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

4. Supplemental Materials
NRC Nutrient Requirements of Dairy Cattle
NRCS Nutrient Management Technical Note 5
LPES Lesson No. 12 Feeding Dairy Cows to Reduce Nutrient Excretion NRC Nutrient Requirements of Beef Cattle
NRCS Nutrient Management Technical Note 2
LPES Lesson No. 13 Using Dietary Strategies to Reduce the Nutrient Excretion of Feedlot Cattle

5. Ruminant Nutrition
You are NOT just feeding the steer or cow! You are also feeding the microorganisms in the rumen.
You must feed and meet the needs of the ruminal microorganisms and the animal.
Speaker Notes:
Ruminant animals differ from monogastric animals because the microorganisms have nutrient requirements in the multi-compartment stomach as well.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

6. Feedlot and Dairy Diets
Forage based
Slowly degraded by rumen microorganisms which create energy pre-cursors
Forage amounts vary from < 10% to 100% of diet
Forages needed for rumen health
Speaker Notes:
Ruminant animals have the ability to maintain and produce on forage-based diets because of the microorganisms found in the rumen.
The end-products of microbial degradation of forage are used by the ruminant animal for energy production.
Forage amounts in ruminant diets can vary to < 10 % (typical feedlot finishing diet) to 100 % (grazing diet)
Some forage is needed to maintain rumen health. Too little forage can lead to acidosis in the animal.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

7. Feedlot and Dairy Diets
Concentrates necessary
More rapidly degraded → pre-cursors created more quickly
Pre-cursors produced from concentrate degradation are not appropriate to maintain animal and production for extended time period
Forage:Concentrate ratio crucial for rumen health and productivity
Speaker Notes:
Concentrates are necessary in most ruminant diets to increase the amount of energy available to the animal.
However, the end-products of concentrate degradation by microorganisms are different than end-products from fiber degradation. Feeding high amounts of concentrate for a period of time can cause acidosis.
Maintaining a proper balance of forages to concentrates (ratio) is necessary to meet production demands and to maintain rumen health.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

8. Dairy Diets Higher digestibilities increase utilization and
Digestibility (availability of nutrients) of forages:
Amount of forage
Type of forage
Maturity of forage
Higher digestibilities increase utilization and
decrease nutrient excretion.
Lower digestibilities
decrease utilization and increase nutrient excretion.
Speaker Notes:
Not all forages are the same. The digestibility of forages is affected by the amount of forage consumed, the type of forage and the maturity of the forage.
The more digestible a forage is, the more an animal will utilize available nutrients. When forages are less digestible, many nutrients are excreted.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

9. Dairy Diets Concentrates 45-60 Forages 40-55 Supplement 2-10
Grains (corn, milo, barley, etc)
Protein meals (soybean meal, Soypass, Cottonseed, distillers grains, etc.)
Byproducts (corn gluten feed, beet pulp, soyhulls, etc.)
Forages
alfalfa hay, corn silage, haylage, grasses
grazing?
Supplement 2-10
dry-pellet, dry-meals, liquid
minerals, protein?, vitamins, additives
Speaker Notes:
As a guideline, typically dairy diets will contain from 45 to 60% concentrates, 40 to 55 % forages and 2 to 10% supplement. Listed on this slide are examples of feed ingredients in a dairy ration depending upon the availability and cost of the feed ingredients for each classification listed.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

10. Relationship between advancing maturity of first cut orchard grass and chemical composition.
Speaker Notes:
In this example with first growth orchard grass, as the maturity of the plant increases, concentration of fiber components (lignin and cellulose) increases and the protein content decreases. The increase in lignin results in a forage that is less digestible (see next slide).
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

11. Relationship between advancing maturity of
first cut orchard grass and digestibility.
Speaker Notes:
With this same sample of orchard grass hay, you can see that as the grass hay matures, the digestibility (availability) of nutrients (in this case dry matter and cellulose) is reduced and very dramatically.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

12. TSP Question to Producer
How do you manage your forages?
Buy or home grown?
Are you maximizing the amount of home grown forages in the ration?
Speaker Notes:
Indicate to the TSP that a couple questions can be asked to the producer regarding forage management in the operation. You want to highlight the awareness of the importance of the quality of the forage on the nutrients in the ration and productivity of the animal. Are they recycling nutrients on-farm through high quality forages and maximizing the use of their forages in the ration?
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

13. Best Management Practices for Forage Utilization
Harvest to optimize protein and reduce fiber; reduces the amount of off-farm N inputs
Use optimal silage
processing techniques
Store different quality forages separately
Analyze silages and forages routinely
Speaker Notes:
Some best management practices for forage utilization are listed on this slide. These include harvesting at the time of maturity to optimize protein and reduce fiber contents, harvest the silages at the right maturity and moisture levels, particle size, etc. to maximize fermentation and preserve nutrients. In addition, one should provide storage for different qualities of forages separately and use them effectively in the rations and have a routine laboratory analysis program for silages and other forages for the operation.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

14. CNMP Core Curriculum Speaker Notes: Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

15. Feedlot Diets Corn/Milo 50-85 Roughage (alfalfa hay, corn silage) 0-10
High-moisture
Dry-rolled
Steam-flaked
Whole
Roughage (alfalfa hay, corn silage) 0-10
Byproducts (distillers/gluten feed) 15-40
Molasses/Liquid 0-5
Supplement 3-8
dry-pellet
liquid
Speaker Notes:
As a guideline, typically beef feedlot diets will contain from 50 to 85% concentrates, 0 to 10 % forages and 3 to 8% supplement. In addition, often by-product feed ingredients are fed at 15 to 40% of the ration and, possibly, molasses or liquid supplements are fed at 0 to 5% of the ration. Listed on this slide are examples of feed ingredients in a beef feedlot ration depending upon the availability and cost of the feed ingredients for each classification listed.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

16. A Few Terms and Definitions
Crude protein (CP) = N x 6.25
Some protein is used by microorganisms in rumen and some are absorbed in small intestine
Rumen degradable protein (RDP) = CP that is degraded in the rumen; required by bacteria to grow (DIP in beef)
Rumen undegradable protein (RUP) = “escape or bypass” CP that is NOT degraded in rumen but passes to lower tract (UIP in beef)
Speaker Notes:
Explain the difference in rumen degradable protein and rumen undegradable protein (for beef cattle, degraded intake protein and undegraded intake protein). Relate this again to nitrogen.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

17. Digestive Process of Ruminants
Sm Intestine
Rumen
Fecal N
RUP AA
MCP
RDP
NPN
Diet CP
MCP AA
Ammonia
Degraded by microorganisms
Urea
Speaker Notes:
( A very simplistic schematic of protein digestion for the ruminant.)
Dietary Crude Protein is consumed by the animal
The RDP and NPN are degraded in the rumen by microorganisms to synthesize microbial crude protein, release free amino acids and produce ammonia.
The MCP and AAs pass into the small intestine where they and the RUP are absorbed by the animal.
The animal uses these forms of N for maintenance and production of milk or meat.
Any N that was not available to the animal for absorption, or any excess protein will be excreted.
The ammonia that was produced in the rumen by the degradation of RDP can be harmful to the animal. There are some microorganisms in the rumen that utilize ammonia. However, when too much ammonia is produced, the number of microorganisms is insufficient to deal with such a large supply. The ammonia will be absorbed through the rumen wall into the blood stream. The ammonia is toxic and must be converted to a different N form by the liver….urea.
When there is too much ammonia in the rumen, the amount of urea excreted in the feces will increase; there will be a higher circulating blood urea nitrogen; and the amount of milk urea nitrogen will increase.
The end result of this schematic should be that milk urea nitrogen can be used as an indicator of protein nutrition in a ruminant animal.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
BUN
Milk Urea N
Milk and Meat
CNMP Core Curriculum

18. Ruminant Nutrition Protein Goals
Provide adequate amount of rumen degradable protein:
For optimal rumen health
For optimal rumen efficiency
Provide adequate amount of rumen undegradable protein:
To obtain the desired animal productivity
Speaker Notes:
(Stressing the goals of protein fractions in ration balancing.)
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

19. Ruminant Nutrition Protein
Excess N excretion typically due to imbalance of RDP and RUP and too much of one, or both
Excess RDP increases ammonia production in rumen which leads to:
Decrease reproductive performance (toxic effect)
Decrease lactation performance (energy cost)
Increases urinary N excretion
Excess RUP:
Not utilized by animal
Increases fecal and urine N excretion
Speaker Notes:
Balancing the protein fractions is not only important for managing nutrient excretion.
Feeding too much RDP will increase ammonia production. There is an associated cost with high rumen ammonia. There is a toxic effect on reproduction, and there is an energy cost….energy that could have been used for production must be used to convert ammonia into urea. Both of these factors are added costs to the producer. In addition, the urinary N excretion will increase, creating an additional cost of managing the extra N for land application.
Feeding excess RUP is also costly. RUP sources are typically very expensive, and overfeeding RUP that isn’t utilized by the animal is wasting money. Also, the excess fecal N must be managed as well.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

20. Ruminant Nutrition Protein N excretion value also varies based on:
Stage and level of lactation or growth
Amount of feed intake
Amount of water intake
Amount of carbohydrates in diet
Digestibility of feed
Speaker Notes:
Even when the appropriate amount of RDP and RUP are provided to the animal, there are other factors that could affect the amount of N utilized by the animal and the amount excreted. List and discuss these factors.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

21. Intake Retention Excretion
Speaker Notes:
In general, the amount of excretion of any nutrient in feces and urine is a result of the amount of nutrient intake minus the retention of the nutrient in the animal. In the case of the lactating dairy cow, the production of milk is a factor that must be considered also in estimating nutrient excretion values.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
Excretion
Intake-Retention=Excretion
Excretion in feces & urine
CNMP Core Curriculum

22. Ruminant Nutrition Protein Estimate N excretion (dairy):
Milk production
Days in milk
Dry matter intake
Body weight
Milk protein content
Concentration of CP in ration
Speaker Notes:
For planning purposes, N excretion for dairy cattle can be estimated using milk production, days in milk, dry matter intake, body weight, milk protein content and the concentration of CP in the ration.
Estimating N excretion should only be used during strategic planning. The resulting number should not be used for annual planning purposes and can be corrected if necessary with nutrient analyses and volume of feed, milk and manure on the farm.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

23. Ruminant Nutrition Protein Estimate N excretion (beef):
Dry matter intake
Concentration of CP in ration
Days on feed for individual ration
Purchase weight (initial weight)
Market weight (ending weight)
Standard reference weight for expected final body fat
Speaker Notes:
N excretion for beef cattle can be estimated using dry matter intake, concentration of CP in the ration, days on feed for each individual ration (as ration may change during the finishing stage), the initial weight of the animals, the ending weight of the animals and a standard reference weight for expected final body fat…. 478kg for Choice (28% marbling) and 462kg for Select (26.8% marbling).
Estimating N excretion should only be used during strategic planning. The resulting number should not be used for annual planning purposes and can be corrected if necessary with nutrient analysis and volume of feed and manure on the farm.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

24. 2-year beef study (protein level)
Overfeeding protein increases N losses!
Nutrition may:
decrease N inputs by 10 to 20%
reduces N excretion by 12 to 21%
reduces N volatilization by 15 to 33%
Based on annual occupancy, lose 50% of N excreted
53.5% annually for control animals, or 103 g/hd/d
48.2% annually for phase-fed animals, or 78 g/hd/d
Speaker Notes:
Nutrition can help this. If you overfeed protein, more N is lost. So, we need to continually evaluate diets and supply just enough protein to optimize performance if we can. We are making progress here and learning more on how to more appropriately supplement protein. Remember, protein contains N, usually about 16% of protein is N. In this example N inputs were reduced, N excretion reduced and N volatilization reduced by phase-feeding beef cattle compared to control-fed cattle.
Required Course Materials:
Supplemental Resources:
Erickson, G. and T. Klopfenstein, In: Nitrogen in the Environment, The Scientific World.
Suggested Learning Exercise:
Nutrition can help this. If you overfeed protein, more N is lost. So, we need to continually evaluate diets and supply just enough protein to optimize performance if we can. We are making progress here and learning more on how to more appropriately supplement protein. Remember, protein contains N, usually about 16% of protein is N.
CNMP Core Curriculum

25. Digestive Process of Ruminants
Phosphorus
Sm Intestine
Rumen
Excess P
Productive functions
Milk
(0.085 to 0.1%)
M/O
Fecal P
Salivary P
Speaker Notes:
(A very simplistic schematic of P digestion and excretion.)
There are two sources of P for the rumen; one is dietary P that is consumed and the other is contributed by the salivary glands during cud chewing.
Both P sources are sent to the rumen where the microorganisms will take up needed P for their functions.
Any P not used by the microorganisms will pass to the small intestine. All available P is absorbed by the animal in the small intestine for maintenance, productive functions and recycling through the salivary glands for rumen buffering. Some P is secreted in milk….ranging from to 0.1% of milk.
Any excess P that is not needed by the animal for maintenance, productive functions or buffering through saliva is dumped back into the small intestine to maintain P homeostasis. Excess P is then excreted in the feces.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
Diet P
CNMP Core Curriculum

26. Ruminant Nutrition Phosphorus Efficiency of P absorption depends on:
Age or body weight
Physiologic state (non-lactating vs lactating)
Amount of dry matter or P intake
Intestinal pH
Ration concentration of nutrients such as Ca, iron, Mg, manganese and K
Source of P (forages, concentrates, inorganic mineral supplements, salivary P)
Good estimates of true P absorption for most feedstuffs do not exist
Speaker Notes:
There are many factors that will affect the efficiency of P absorption: age or body weight, the physiological state of the animal, the amount of P consumed, intestinal pH, the dietary concentration of calcium, iron, magnesium, manganese and potassium (minerals interact with one another….a surplus in one could cause a deficiency in another and vice versa). The source of P is also very important. Some forms of P are more available than other forms.
At this time sufficient studies to estimate the true P absorption for most feedstuffs do not exist.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

27. Ruminant Nutrition Phosphorus Estimated P excretion (dairy):
Dry matter intake
Amount of P in ration
Milk production
Amount of P in milk (~ 0.10%)
Speaker Notes:
Like N, P excretion can be estimated for dairy cattle using dry matter intake, the concentration of P in the ration, milk production and the amount of P in the milk (the standard concentration is 0.10%).
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

28. Ruminant Nutrition Phosphorus Estimated P excretion (beef):
Dry matter intake
Concentration of P in ration
Days on individual ration
Purchase weight (initial weight)
Market weight (final weight)
Standard reference weight
Speaker Notes:
Likewise P excretion can be estimated for beef cattle as well with the same factors as with nitrogen. Briefly list these factors again.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

29. TSP Question to Producer
Are the rations reformulated when there are different ingredient changes?
Are rations changed at different stages in the production cycle?
What is the laboratory analysis schedule for the feed management plan?
Are by-product feeds being used in the ration?
Speaker Notes:
Indicate that the TSP may ask some questions to the producer regarding when rations are formulated and are the rations changed at different stages in the production cycle. Are rations reformulated when new sources of feed ingredients are added? Since by-product feeds are so variable and there is a possibility of excess nutrients being fed, one can ask if by-product feeds are being use in the ration. Again, is there a laboratory analysis schedule in the feed management plan on the farm?
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

30. Dietary P in Feedlot Diets
0.27
0.35
0.52
0.59
0.1
0.2
0.3
0.4
0.5
0.6
0.7
85% Corn
85% Corn +
Supplement
Byproduct
Byproduct +
% diet P (DM-basis)
Corn
Roughage
Speaker Notes:
The amount of P in the ration can dramatically change depending what ingredients are used in the ration. The total P in these rations which is based upon corn are increased with the addition of a supplement, by-products such as DDGS or corn gluten, etc. and with the combination of the by-products and supplement. However, the requirements of P for beef cattle is met with corn grain alone.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
NRC
CNMP Core Curriculum

31. P requirements NRC corn industry CNMP Core Curriculum Speaker Notes:
This graph shows that as you increase the P intake for growing beef cattle there will be an increased average daily gain (ADG) in the cattle up to what the P requirement is and then there will be no additional benefit with increasing the P intake of the cattle. Depending upon the age of the cattle, the NRC predicts the P requirements from 0.22% to 0.32% of the diet dry matter. However, again, the requirements of P for beef cattle is met with corn grain alone. The industry average is higher than corn because of supplemental P added to the ration. This used as a safety margin, but it is not needed and is a waste of money for the producer.
Required Course Materials:
Supplemental Resources:
Giesert et al., 2004 Nebraska Beef Report
Suggested Learning Exercise:
NRC
corn
industry
CNMP Core Curriculum

32. P Mass Balance: Summer Yearlings
Feedlot Pen
7.2 lb P
intake
1.9 lb P retained
5.3 lb
excreted
12.8 lb P
10.9 lb
0.35% P diet
0.24% P diet
REDUCED
44%
Speaker Notes:
This slide shows an example of what can be done with beef cattle rations in a summer yearling study by just reducing the amount of excess P fed in the diet. The diet P was reduced by 44% which reduced P excretion by 31% (10.9 lbs versus 5.3 lbs in the feeding period)
Required Course Materials:
Supplemental Resources:
Erickson et al., ISAAFPW, 2000
Suggested Learning Exercise:
Values for the entire feeding period
CNMP Core Curriculum

33. P Mass Balance: Winter/Spring Calves
Feedlot Pen
2.5 lb P
retained
12.5 lb
excreted
0.40% P diet
15.0 lb P
intake
Speaker Notes:
Another example of what can be done with beef cattle rations in a winter/spring calf study by just reducing the amount of excess P fed in the diet. The diet P was reduced by 33% which reduced P excretion by 35% (12.5 lbs versus 7.5 lbs in the feeding period)
Required Course Materials:
Supplemental Resources:
Erickson et al., ISAAFPW, 2000
Suggested Learning Exercise:
REDUCED
33%
2.4 lb P
retained
7.5 lb
excreted
0.26% P diet
9.9 lb P
intake
Values for the entire feeding period
CNMP Core Curriculum

34. Dietary P effect on excretion
Y = x x ; r2 = 0.74
Speaker Notes:
This graph shows that as the intake of P increases above the requirement of the beef animal, there is an liner increase in P excretion.
Required Course Materials:
Supplemental Resources:
Meyer and Trenkle, ISU research
Suggested Learning Exercise:
CNMP Core Curriculum

35. Land Requirements, 4 yr P basis (acres)
,000 25,000
0 byp 0.29 P 1,320 5,300 13,200
20 byp 0.39 P 1,900 7,600 19,000
40 byp 0.49 P 2,500 10,000 25,000
Speaker Notes:
This table illustrates that as you increase the amount of a by-product feed ingredient in the beef feedlot diet, there is a significant increase in the amount of land required for manure application on a 4-yr P application basis. This also increases with the size of the feedlot operation.
Required Course Materials:
Supplemental Resources:
Kissinger et al., 2006 NE Beef Report
Suggested Learning Exercise:
CNMP Core Curriculum

36. Costs and Net Value, C-SB rotation 4-Yr P Basis, ($/hd)
,000 25,000
COSTS
0 byp 0.29 P
20 byp 0.39 P
40 byp 0.49 P
NET VALUE
0 byp 0.29 P
20 byp 0.39 P
40 byp 0.49 P
Speaker Notes:
This table illustrates the relationship of costs and the net manure value of applying the manure to distant cropland when increased P is in the diet is from increased amounts of by-products included in the ration. The producer of different sized operations needs to evaluate at what level of by-product inclusion when the cost of application exceeds the net value return from the manure as a fertilizer resource for a corn-soybean rotation. This is on a 4-yr P application basis.
Required Course Materials:
Supplemental Resources:
Kissinger et al., 2006 NE Beef Report
Suggested Learning Exercise:
CNMP Core Curriculum

37. Potassium Considerations
Ruminant Nutrition
Potassium Considerations
Required by crops and animals
Can be highly toxic to ruminant animals
High K diets:
Interfere with Mg absorption = grass tetany
Interfere with Ca metabolism = milk fever
Many forage species have ability to “luxury uptake” K
Apply only what is needed by crop
Speaker Notes:
One nutrient not mentioned thus far that has some environmental implications is potassium. It is often forgotten about when applying fertilizer and manure to crops.
K is also an important nutrient for ruminants, but is highly toxic.
Potassium interferes with Mg absorption, causing a Mg deficiency (or grass tetany); and it interferes with Ca metabolism, causing a Ca deficiency (or milk fever) at the onset of lactation.
Unfortunately, many forage species have the ability to absorb more K than the plant needs (also known as luxury uptake). This increases the K in the forage is available to the animal. In some cases, the K level in the forage alone can be above the Maximum Tolerable Concentration of 3.0%
Although K may not pose as much risk to the environment as N or P, it can pose a significant risk to cattle health. Therefore, when possible, only apply the amount of K that will be needed by the crop (especially grass species). If more must be applied, the producer should be made aware of potentially toxic forage.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

38. Ration Balancing CNMP Core Curriculum Speaker Notes:
Balancing rations is not simply using equations to derived at a desirable number. More thought must be put into it.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

39. Balancing Ruminant Rations
Straddling the line of pushing and pushing too far
Diverse population with different nutritional needs; stage of lactation
Overfeed vs Underfeed
Dynamic beings with ever-changing environmental conditions, health and diet
Ingredient challenges
Speaker Notes:
When balancing a ration, nutritionists are faced with numerous challenges.
In many cases, nutritionists are encouraged by producers to push the animals as hard as they can to achieve maximum production, but not so far as to jeopardize the health of the animals.
Secondly, the nutrient needs of every animal within a herd are not the same. Many times you have one ration to meet the needs of several different groups. There will be times when some animals are overfed nutrients; and there will be times when some animals are underfed. Nutritionists must determine how much they can overfeed or underfeed and not lose production due to fat cows or thin cows.
Third, ruminant animals are not static beings. As their environment or their health changes, their nutritional needs will change. Also, as a diet is changed, the population of rumen microorganisms will change.
And last, one of the biggest challenges a nutritionist may face are the diversity of ingredients being used in the ration and their variable nutrient compositions.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

40. Balancing Ruminant Rations
Ingredient Challenges
Ingredients themselves can be a challenge
Bakery waste
Candy waste
Apple pies!
Inconsistency in nutrient content
Different for each region, differences between plants within region, differences within plant from week to week
Ingredients available will not perfectly balance for all ingredients
Speaker Notes:
Ingredients used in a ration can be challenging because of the inconsistent nature of them. Bakery Waste and Candy Waste can be an excellent source of carbohydrates, but the composition of the waste will vary greatly from day to day.
The nutrient content of by-products will vary from region to region; plants within regions will differ; and in some cases there will be variations within the same plant from week to week (excellent example is distillers grains with solubles).
Additionally, the NRC provides recommended requirements for over 25 different nutrients. It is nearly impossible to combine ingredients to meet the exact recommendation for all nutrients. Most nutritionists will target specific nutrients that they wish to meet….energy, protein, fiber, NFC, Ca, P, or other nutrients. If they can meet those requirements with a group of ingredients, other nutrients may be overlooked unless they are severely deficient or at a dangerous toxic level. This is known as “forcing a ration.”
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

41. Balancing Ruminant Rations
Ingredient Challenges
Book values vs Ingredient testing:
Book values have limited value
Ingredient testing only as good as the sample taken
Speaker Notes:
An additional challenge that ingredients pose is knowing what their nutrient composition is.
Book values are averages taken from samples across the country. Although samples from a specific area would be included in the US population, the regional average and the US average could be completely different.
Also, ingredient testing has its limitations as well. If the sample taken is not truly representative of the entire population (the entire silo, commodity bin, etc.), then its value is limited.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

42. Balancing Ruminant Rations
Ingredient Challenges
“Unbreakable Law of Sampling: You never know the true value of anything”
-Bill Weiss, OSU
Speaker Notes:
Whether sampling feed ingredients or manure, you are merely estimating the composition of it. That is why obtaining a truly representative sample of a feed ingredient is necessary. Anytime the feed changes….a new truck load, moisture level change, silage from a new silo, silage harvested from a different field…..a new sample should be taken. And the ration should be adjusted to those changes.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

43. Balancing Ruminant Rations
Ingredient Challenges
Numbers are not absolute!
20 tons of feedstuff
1 lb sample sent to lab
(1/40,000)
Speaker Notes:
The results from analysis are not absolute.
If you sample 20 tons of any feed, typically only one pound of that sample will be sent to the lab. This is 1/40,000 of the total load of feed. In the lab, they will take one gram of that sample to analyze. This only represents 1/18,000,000 of that load of feed. How accurate do you believe the results will be?
Using correct sampling procedures will enhance your confidence in the results.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
1 g sub-sample analyzed
(1/18,000,000)
CNMP Core Curriculum

44. Strategies to Reduce N & P
Realize that in every feeding environment, there are three rations:
Speaker Notes:
Before discussing those strategies, it is important to realize how the real world of feed management works.
For every feeding environment, there are three different rations:
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

45. 1. The ration balanced on a computer
Speaker Notes:
First, there is the ration that is balanced on the computer. This ration is only as good as the samples analyzed. If the process starts with samples that are not true representatives of the ingredients, the ration that is balanced on paper will not be representative of what is being fed.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

46. 2. The ration mixed on the farm
Speaker Notes:
Secondly, even if the ingredients were sampled correctly and the ration was balanced perfectly, once the ‘paper ration’ is handed to the producer, it is their responsibility to mix it. Accurate weighing and mixing is the key to achieving the desired ration. A five gallon bucket would not be an accurate measuring device. Also, it is important to realize that when dealing with large quantities of ingredients, mistakes will happen. If a ration calls for 200 lbs of an ingredient, and 210 lbs are dumped into the mix wagon, how likely is it that someone will shovel out that extra 10 lbs?
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

47. 3. The ration consumed by the animal
Speaker Notes:
Third, after the ration is balanced, mixed and delivered to the animals, you can only hope that they will consume everything you have supplied. If the ration contains components that easily settle out, are unpalatable or easily sorted through, the animals will not consume the total mix.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

48. Balancing Ruminant Rations
Meeting the Requirements of the Herd
If herd average is 77 lbs:
Overfeeding cows producing 55 lbs
Excess nutrients leads to weight gain leading to health problems and lowered production
Underfeeding cows that could produce 120 lbs
Not providing enough nutrients to meet genetic potential
Not taking advantage of “money-makers”
Fresh cows producing 77 lbs have different requirements
If do not meet nutritional needs of fresh cow, entire lactation will be negatively affected: lost production and health issues
Who do you balance the ration for?
Speaker Notes:
Think this question through…..”What do you balance the ration for???”
If the herd averages 77 lbs, and the ration is balanced for cows producing 77 lbs:
Then cows only producing 55 lbs of feed will gain too much weight which will lead to health problems and lowered production.
The cows that could produce up to 120 lbs will not receive enough nutrients to meet their genetic potential. The producer will be short changed because these cattle could produce the most profit.
Fresh cows won’t receive enough nutrients which could lead to health issues and negatively affect their entire lactation.
Therefore, balancing a ration for the average is probably not the answer.
(The answer is still to come…)
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

49. Feeding Management: The Bottom Line
The milking herd should be grouped by production level so that multiple rations can be formulated over the complete lactation.
Similarly, growing feedlot beef cattle should be grouped by sex, age and production potential so that multiple rations can be fed over the growth period.
Speaker Notes:
A best management practice to reduce feed cost and reduce nutrient excretion is to group the milk herd by production level and provide multiple rations (TMR) over the entire lactation period. Similarly, grouping feedlot beef cattle by sex, age and production potential (different genetics) is recommended with a phase feeding program.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

50. Overfeeding Nutrients
Speaker Notes:
There may be times when overfeeding of nutrients is required.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

51. Overfeeding Nutrients
In the short run, it is more profitable to overfeed a nutrient because underfeeding will negatively impact production.
Speaker Notes:
For producers, it’s more profitable to overfeed nutrients than limit production from underfeeding nutrients. However, for some nutrients, long-term overfeeding can cause chronic conditions.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

52. Why overfeed protein? Ingredient variability between batches
Uncertainty in protein fractions
Feeding to meet demands of highest producers
Belief that more protein will increase growth, milk yield or milk protein
Uncertainty in recommended nutrient requirements
Heat stress
More buffer needed for “hot” rations
Speaker Notes:
Because of high variation in nutrient content of some ingredients, nutritionists will sometimes formulate the ration at a lower level for that nutrient. For example, if ingredient X is highly variable in CP and the analysis indicates that it has 8% CP, it would be formulated with 6% CP to minimize underfeeding of CP.
Not all labs will analyze for RUP and RDP unless asked or with additional fees. If RDP or RUP isn’t known and the ration is formulated using CP, a lower level of CP may be used to minimize underfeeding RDP or RUP.
In some cases, producers want to maximize the production and rations are formulated for the highest producers.
There is a myth that feeding more protein will increase growth, milk yield or milk protein. This would only be true if energy and other nutrients were increased as well, and the animal had the genetic potential for a higher level of production.
Other factors such as heat stress and the need to add protein to buffer the pH for high concentrate (“hot”) rations are situations when one may add more protein to the diet. During heat stress, animals tend to reduce feed intake, so a higher concentration of protein is fed so that the total protein level consumed each day is adequate.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

53. Why overfeed phosphorus?
Ingredient variability between batches
Uncertainty in recommended levels
Feeding to meet demands of highest producers
Heat stress
More buffer needed for “hot” rations
As with protein, the P content of some feeds is highly variable.
The current recommendations for P content of a total ration is lower than it was 4 years ago. The animals haven’t changed a tremendous amount within that time frame, so their actual requirements haven’t changed. The lowering of the P content was a result of more research, and a more precise estimate of the animals’ needs. However, getting everyone to buy in on the concept that our recommendations are better now than before can be difficult.
Again, higher producers need more P, and balancing the ration for the highest producers will lead to overfeeding P to lower producers.
During heat stress, most producers will decrease the amount of forage fiber in the ration because degrading and fermenting forage in the rumen creates heat. In addition, because feed intake level often is reduced during heat stress, a higher level of P is added to the diet so that the amount of P consumed per day is adequate. However, the forage in the diet also helps maintain a proper pH of the rumen. Therefore, when forage content is dropped, more P is needed for buffering the rumen.
A ‘hot’ ration is one that contains minimal forage or rapidly digested fiber and high concentrate amounts. These types of diets need more P to help buffer the rumen and maintain a proper pH.
CNMP Core Curriculum

54. Why overfeed phosphorus?
Result of forcing a ration
Concerns regarding Ca utilization
“More is better” – no negative performance effects
Belief that reproductive performance will suffer without abundance of P
Speaker Notes:
Typically, when balancing a ration, P is not the major nutrient of concern. Overfeeding P will not harm the animal because of their ability to maintain homeostasis. So, when forcing a ration to meet energy, protein or some other requirement, overfeeding P is not a concern.
In the past, nutritionists thought that you had to maintain a balance of Ca:P ratio of 2:1. However, more research has shown that cattle can tolerate wide ranges in that ratio.
Since there is no negative performance effects with overfeeding P, there is some attitude that more than is required must be better.
In the 1920’s and 1930’s, there were many studies that indicated a deficiency in P would cause a decline in reproductive performance. This led to the fear of underfeeding P, and led to the belief that overfeeding must increase reproductive performance. Recent research has yet to prove that overfeeding P will increase reproductive performance.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

55. Reducing N and P Excretion with Feed Management
Speaker Notes:
Despite the challenges of ration balancing, there are ways to reduce N and P excretion through improved feed management.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
Reducing N and P Excretion with Feed Management
CNMP Core Curriculum

56. Nitrogen Strategies for Dairy
Increase dry matter uptake.
Improve forage quality.
Evaluate balance of types of home grown forages and other feed ingredients available.
Consider forage protein fraction.
Consider feeding method (phase and TMR).
Consider supplemental protein source.
Monitor blood urea nitrogen (BUN) and milk urea nitrogen (MUN).
Speaker Notes:
Following are listed some nitrogen strategies for dairy.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

57. Beef Strategies Test feed for nutrients and dry matter.
Use supplemental protein to balance RDP and RUP.
Discontinue supplemental P.
Consider phase feeding.
Use available tools to evaluate your rations.
Speaker Notes:
Following are some feed management strategies for beef.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

58. Questions?

59. P Mass Balance – Example CNMP
Manure
P2O5 Produced
= (44.82 lbs. avg. feed intake (%dm) x *) - (65 lbs. avg. milk prod. per cow/day** x 0.001***) x 2.29****
= lbs. P per day per cow x 2.29
= 0.22 lbs. P2O5 per day per cow x 175 cows x 365 days
= 14,094 lbs P2O5 per year
Acres Required for P2O5 Mass Balance
= 14,094 / 65 lbs. P2O5 removed by crop
= 217 acres X 50% confinement
= 108 acres
*0.36 % of P in total feed ration from feed analysis
**Based on 2000/2001 rolling herd average of lbs. of milk produced per cow per year
***0.10 % of P in milk; ****conversion of P to P2O5
Speaker Notes:
Here is the data for the example dairy that we discussed earlier. This is the amount of P2O5 produced each day and the acres required for land application of manure based upon the P2O5 removed from the crop and assuming only 50% of the time that the dairy cows are in confinement. This is with a typical dairy ration with 0.36% P in the diet.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

60. Class Exercise (Ruminants)
Calculate P excretion for the example CNMP dairy if they use 25% DDGS in place of corn silage and milled feed.
Calculate the amount of land needed to apply the P2O5 (assume 65 lbs of P2O5 needed for corn silage/acre) from the manure from cows fed this new ration (assume that only 50% of the time the cows are in confinement)
Speaker Notes:
What is the excretion of the example CNMP dairy if 25% DDGS replaces the corn silage and milled feed in the diet?
Required Course Materials:
Calculator
Supplemental Resources:
Suggested Learning Exercise:
Have the problem in the learning exercise book and the answers in the answer section.
CNMP Core Curriculum

61. Class Exercise (Ruminants)
Calculate P excretion for the example CNMP dairy if they use 25% DDGS in place of corn silage and milled feed.
What do you need to know?
DMI, diet composition, milk production
Speaker Notes:
What do we need to know? The dry matter intake (DMI), diet composition and the milk production.
Required Course Materials:
Calculator
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

62. Class Exercise (Ruminants)
Calculate P excretion for the example CNMP dairy if they use 25% DDGS in place of corn silage and milled feed.
What do you need to know?
DMI = lb per day
Diet composition (DDGS contains 0.90% P, so diet will be 0.51% P)
Milk production = 65 lb per day
175 cows still
Speaker Notes:
Therefore, assume the same dry matter intake (44.82 lbs/day), the P in the diet will be increased to 0.51%, the milk production stays the same (65 lbs /day) and we still have 175 cows.
Required Course Materials:
Calculator
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

63. Class Exercise (Ruminants)
Calculate P205 excretion for the example CNMP dairy with 0.51% P in the diet
Calculate the amount of land needed to apply the P2O5 (assume 65 lbs of P2O5 needed for corn silage/acre) from the manure from cows fed this new ration (assume that only 50% of the time the cows are in confinement)
Speaker Notes:
Calculate the P2O5 excretion when 0.51% P is in the diet and calculate the amount of land needed for manure from cows fed this diet. Assume only 50% confinement and that 65 lbs of P2O5 is removed by the corn silage per acre.
Required Course Materials:
Calculator
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

64. Class Exercise (Answer)
Manure
P2O5 Produced
= (44.82 lbs. avg. feed intake (%dm) x *) - (65 lbs. avg. milk prod. per cow/day** x 0.001***) x 2.29****
= lbs. P per day per cow x 2.29
= lbs. P2O5 per day per cow x 175 cows x 365 days
= 23,953 lbs P2O5 per year
Acres Required for P2O5 Mass Balance
= 23,953 / 65 lbs. P2O5 removed by crop
= 368 acres X 50% confinement
= 184 acres
*0.51 % of P in total feed ration from feed analysis
**Based on 2000/2001 rolling herd average of lbs. of milk produced per cow per year
***0.10 % of P in milk; ****conversion of P to P2O5
Speaker Notes:
Go over this table again showing how just by adding more P in the diet will increase P excretion and the amount of land needed for manure application at agronomic rates (P basis).
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

65. Class Exercise (Answer)
Difference in P2O5 produced:
23,953 lbs – 14,094 lbs = 9,859 lbs more produced; however, only 50% confinement, so 4,930 lbs collected and stored.
Difference in acres of land required (assuming 50% confinement):
184 acres – 108 acres = 76 acres more needed
If all the manure was collected (100% confinement, then 151 acres more needed
Speaker Notes:
The differences in P excretion and acres needed for manure application from adding more P in the diet are listed on this slide. Emphasize that if all manure was collected on this farm with 175 cows that the acreage required for manure application would increase substantially. As it is, with only 50% confinement, 76 more acres are needed with just using 25% dried distillers grains with solubles in the diet.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum

66. Computer Software Tools
Dairy Whole Farm Balance Nutrition Education Tool (WFBNET) –
Whole Farm Balance – on CNMP Course CD and at
Nutrient and Land Estimator – on CNMP Course CD and at
Speaker Notes:
There are computer tools that can be used to help determine the effects of diet changes on the nutrient balance on a farm and to determine the amount of land required for application of the manure. This software is free and can be downloaded from the websites listed on this slide.
Required Course Materials:
Supplemental Resources:
Suggested Learning Exercise:
CNMP Core Curriculum