Chapter 19 Dairy ration formulation.
Workbook A workbook is the spreadsheet program file including all its worksheets.
Worksheet A worksheet is the same as a spreadsheet. There may be more than one worksheet in a workbook.
Spreadsheet A spreadsheet is the same as a worksheet.
Cell A cell is a location within a worksheet or spreadsheet.
Comment A comment is a note that appears when the mouse pointer moves over the cell. A red triangle in the upper right corner of a cell indicates that it contains a comment. Comments are added to help explain the function and operations of workbooks.
Input box An input box is a programming technique that prompts the workbook user to type information. After typing the information in the input box, the user clicks OK or strikes ENTER to enter the typed information.
Message box A message box is a programming technique that displays a message. The message box disappears after the user clicks OK or strikes ENTER.
Security: Click on the Tools menu, Options command, Security tab, Macro Security button, Medium setting.
Screen resolution: This application was developed for a screen resolution of 1024 x 768. If the screen resolution on your machine needs to be changed, see Microsoft Excel Help, "Change the screen resolution" for instructions.
DAIRY RATION FORMULATION
Double click on the DairyRation icon. The message box in Figure 19-1 displays.
Figure 19-1 Macros may contain viruses. It is advisable to disable macros, but if the macros are legitimate, you may lose some functionality. Disable Macros or Enable Macros or More Info
Click on Enable macros. The message box in Figure 19-2 displays.
Figure 19-2 Function keys F1 to F10 are set up. You may return to this location from anywhere by striking ENTER, then the F1 key. Workbook by David A. Tisch. The author makes no claim for the accuracy of this application and the user is solely responsible for risk of use. You're good to go. TYPE ONLY IN THE GRAY CELLS! Note: This workbook is made up of charts and a worksheet. The charts and worksheet are selected by clicking on the tabs at the bottom of the display. Never save the workbook from a chart; always return to the worksheet before saving the Workbook.
Input Dairy Animal Procedure
Click on the Input Dairy Animal button. The input box shown in Figure 19-3 displays.
Figure 19-3 1. Lactating 2. Dry cow 3. Replacement heifer. ENTER THE APPROPRIATE NUMBER:
Click OK to choose the default input of #1, the Lactating dairy animal. The input box shown in Figure 19-4 displays.
Figure 19-4 Enter measured DMI (pounds) if available or click OK to accept the predicted value at CX26.
Click OK to accept the predicted dry matter intake. The message box shown in Figure 19-5 displays.
Figure 19-5 Enter the appropriate Cell Inputs in column CX; then click the ENVIRONMENT INPUTS button to continue.
The Cell Inputs
Enter the cell inputs in Table 19-1. Comments associated with the cell inputs follow.
The comment behind the cell containing the Condition Score label is shown in Table 19-2.
The comment behind the cell containing the Breed label is shown in Figure 19-6.
Figure 19-6 Breed effects on nutrient requirements are minimal. The breed selected will determine mature weight and calf birth weight, which will affect growth requirements.
The information below the input section is shown in Figure 19-7. Note associated comments behind these cells.
Figure 19-7 84 Cow Milk Potential (lb.) based on where the cow is on the herd's lactation curve. NOT AN INPUT. 0.0 Target ADG (lb.) to meet growth targets. NOT AN INPUT.
Click on the button at the bottom of the Animal Inputs display to go to the Environment Inputs section and enter the values shown in Table 19-3.
The comment behind the cell containing the Heat Stress label is shown in Figure 19-8.
Figure 19-8 Enter 1 if no heat stress, 2 for rapid/shallow panting, 3 for open-mouth panting.
Strike ENTER and F1 to return to the home display.
Select Feeds Procedure
Click on the Select Feeds button. The note in Figure 19-9 displays.
Figure 19-9 Nutrient content expressed on a dry matter basis. Feedstuffs are listed first by selection status, then, within the same selection status, by decreasing protein content, then, within the same protein content, alphabetically. Feedstuff DE and NDFdig are calculated values--strike F10 to calculate these values after entering new analysis values.
Explore the table. Note the nutrients listed as column headings. Note also that the table ends at row 200. You select feedstuffs for use in making two different products: (1) a blend to be mixed and sold
bagged or bulk, and (2) the ration to be fed directly to livestock.
Select the feedstuffs in Table 19-4 by placing a 1 in the column to the left of the feedstuff name. All unselected feedstuffs should have a 0 value in the column to the left of the feedstuff name. If you wish to group feedstuffs but not select them, you would place a value between 0 and 1 to the left of the feedstuff name.
Strike ENTER and F2.
Selected feedstuffs and their analyses are copied to several locations in the workbook.
Make Ration Procedure
Click on the Make Ration button. The message box shown in Figure 19-10 displays.
Figure 19-10 ENTER POUNDS TO FEED IN COLUMN B. TOGGLE BETWEEN NUTRIENT WEIGHTS AND CONCENTRATIONS USING THE F5 KEY, RATION AND FEED CONTRIBUTIONS USING THE F6 KEY, AMINO ACID FLOWS USING THE F7 KEY, AND ENERGY CALCULATIONS USING THE F9 KEY. WHEN DONE STRIKE F1. Cell is highlighted in red if nutrient provided is poorly matched with nutrient target. The lower limit is taken as 94 to 98 percent of target, depending on the nutrient. The upper limit of acceptable mineral is taken from National Research Council. 1980. Mineral Tolerance of Domestic Animals. National Academy Press. This publication gives safe upper limits of minerals as salts of high bioavailability, which corresponds to the values calculated here. Vitamin limits are taken from the NRC, 1987. For other nutrients, the upper limit is based on unreasonable excess and the expense of unnecessary supplementation. See Table 19-6 for specifics.
The message box in Figure 19-11 displays.
Figure 19-11 The Goal Seek feature may be useful in finding the pounds of a specific feedstuff needed to reach a particular nutrient target: 1. Select the red cell highlighting the deficient nutrient 2. From the menu bar, select Tools, then Goal Seek 3. In the text box, "To Value:" enter the target to the right of the selected cell 4. Click in the text box, "By changing cell:" and then click in the gray "Pounds fed" area for the feedstuff to supply the nutrient 5. Click OK. You may accept the value found by clicking OK or reject it by clicking Cancel. WARNING: Using Goal Seek to solve the unsolvable (e.g., asking it to make up an iodine shortfall with iron sulfate) may result in damage to the Workbook. IMPORTANT: If you return to the Feedtable to remove more than 1 one feedstuff from the selected list, you will lose your chosen amounts fed in the developing ration.
In the gray area to the right of the feedstuff name, enter the pound values shown in Table 19-5.
The Nutrients Supplied Display
The application highlights ration nutrient levels, expressed as amount supplied per dairy animal per day, that fall outside the acceptable range.
The lower limit for DMI is 94 percent of the target. With the exception of energy and protein, the lower limit for all ration nutrients is taken as 98 percent of the target. Energy and protein levels are used to predict performance so no limits are set. Table 19-6 shows the upper limits of the acceptable range for the various inputs.
The Nutrients Supplied display shows nutrient amounts supplied in the diet and nutrient targets for the inputted lactating dairy animal. All nutrient levels appear to be within acceptable ranges as established by the application.
The cost of this ration using initial dollar-per-ton values is $3.49 per head per day.
Milk supported by energy (lb.): 87
The comment behind the cell containing the Milk Supported by Energy label is shown in Figure 19-12.
Figure 19-12 Note that the urea cost is a maintenance energy cost and that it has been added to the maintenance energy required.
The comment behind the cell showing the predicted pounds milk supported by energy is shown in Figure 19-13.
Figure 19-13 This is the milk production (in pounds) that is supported by the level of energy in the diet.
Milk supported by protein (lb.): 82
The comment behind the cell containing the Milk Supported by Protein label is shown in Figure 19-14.
Figure 19-14 Ration protein and energy content should support similar levels of performance--otherwise nutrients are wasted. This waste may be acceptable if it does not adversely affect profitability, the environment, or animal health. In early lactation, it may be desirable to formulate the ration so that dietary protein will support slightly more milk production than dietary energy, because the animal can use energy reserves in body fat in addition to feed energy to support milk production. In later lactation, the animal should receive a ration that allows her to restore her energy reserves in body fat.
The comment behind the cell showing the predicted pounds milk supported by protein is shown in Figure 19-15.
Figure 19-15 This is the milk production (in pounds) that is supported by the level of protein in the diet. The level of milk supported by the protein content should be within 15 percent of that supported by the energy content.
Milk supported by methionine: 119
The comment behind the cell showing the predicted pounds milk supported by the first limiting amino acid is shown in Figure 19-16.
Figure 19-16 This is the milk production (in pounds) that is supported by the level of the first limiting amino acid in the diet (see notes at F7).
Max milk supported: 82
The comment behind the cell containing this label is shown in Figure 19-17.
Figure 19-17 If the max milk supported is significantly greater than the cow milk potential, cows may not be able to realize the milk production supported by this ration. Excess nutrients will be excreted.
Cow milk potential: 84
The comment behind the cell containing this label is shown in Figure 19-18.
Figure 19-18 This is the predicted amount of milk that this cow is capable of making based on the inputs.
IOF (Income Over Feed) cost using max milk: $6.40
The comment behind the cell containing this label is shown in Figure 19-19.
Figure 19-19 IOF (Iincome Over Feed) cost is calculated here as follows: [(inputted milk price/100) x max milk supported]--ration cost Note that the IOF cost using max milk increases with increasing max milk supported. However, if the max milk supported is greater than the cow milk potential, the excess nutrients will go into storage or be excreted.
IOF (Income Over Feed) cost using cow milk potential: $6.56
The comment behind the cell containing this label is shown in Figure 19-20.
Figure 19-20 IOF cost is calculated here as follows: (inputted milk price/100 x cow milk potential)--ration cost Because cow milk potential is a fixed value based on animal and environment inputs, IOF cost using cow milk potential decreases with increasing ration cost. Pounds Percent RDP 6.13 64.02
The comment behind the cell containing this label is shown in Figure 19-21.
Figure 19-21 RDP is rumen degradable protein. It is the portion of feed protein that rumen microbes can use for food. In most diets, RDP should be greater than RUP because RDP is cheaper and usually the microbes grown on RDP deliver a better-quality protein to the mammary gland.
The comment behind the cell containing the percent RDP value is shown in Figure 19-22.
Figure 19-22 Percentage of crude protein. Pounds Percent RUP 3.45 35.98
The comment behind the cell containing this label is shown in Figure 19-23.
Figure 19-23 RUP is rumen undegradable protein. This is the portion of feed protein that bypasses the rumen microbes and goes directly to the small intestine. If digestible and metabolizable, it then is delivered to the tissues and mammary gland.
The comment behind the cell containing the percent RUP value is shown in Figure 19-24
Figure 19-24 Percentage of crude protein. Pounds Percent MP-bacteria 2.87 48.15
The comment behind the cell containing this label is shown in Figure 19-25.
Figure 19-25 MP-Bacteria is the metabolizable protein from the bacterial cells grown in the rumen on the feed's RDP (rumen degradable protein). 45 to 80 percent of the nitrogen reaching the small intestine is of microbial origin.
The comment behind the cell containing the percent MP-bacteria value is shown in Figure 19-26.
Figure 19-26 MP-bacteria percentage: percentage of total metabolizable protein. Pounds Percent MP-RUP 2.83 47.59
The comment behind the cell containing this label is shown in Figure 19-27.
Figure 19-27 MP-RUP is the portion of the feed protein that is not degraded in the rumen (rumen undegradable protein), yet is digestible and metabolizable. It is also known as bypass protein. Though most nutritionists recommend that most of the total MP come from MP-bacteria, higher producers will generally have to have a greater proportion of their total MP coming from RUP.
The comment behind the cell containing the percent MP-RUP value is shown in Figure 19-28.
Figure 19-28 MP-RUP percentage: percentage of total metabolizable protein. In most rations, this should not be as great as the MP produced in the rumen by bacteria. Pounds Percent MP-Endogenous 0.25 4.27
The comment behind the cell containing this label is shown in Figure 19-29.
Figure 19-29 MP-endogenous includes metabolizable protein coming from sloughed epithelial cells in the digestive and respiratory systems as well as enzyme secretions into the abomasum.
The comment behind the cell containing the percent MP-endogenous value is shown in Figure 19-30.
Figure 19-30 MP-endogenous percentage: percentage of total metabolizable protein. Pounds Percent MP total 5.95 11.06
The comment behind the cell containing this label is shown in Figure 19-31.
Figure 19-31 MP is Metabolizable Protein, and the total level provided is the sum of MP from bacteria, MP from RUP and MP from endogenous sources. Maximizing MP total is an important goal in feeding ruminants and requires an understanding of the impact of different feeding management strategies on the supply of MP-Bacteria and MP-RUP.
The comment behind the cell containing the percent MP total value is shown in Figure 19-32.
Figure 19-32 MP total percentage: percentage of DMI. Pounds Percent CP total 9.58 17.79
The comment behind the cell containing this label is shown in Figure 19-33.
Figure 19-33 Crude protein is measured as 6.25 x (the feed nitrogen content). Because other feed components besides protein contain nitrogen, it is described as crude protein.
The comment behind the cell containing the percent CP total value is shown in Figure 19-34.
Figure 19-34 CP total percentage: percentage of DMI. Mcal UREA cost 0.00
The comment behind the cell containing this label is shown in Figure 19-35.
Figure 19-35 The urea cost is the cost in Mcal of ME to dispose of the nitrogen in the ration's unused protein. This amount of energy becomes part of the maintenance requirement at the expense of other functions. Approximately 0.52 Mcal of ME is used to make 1 lb. of milk containing 3.5 percent fat. Therefore, if energy is limiting production, each multiple of 0.52 ME used in protein excretion results in a pound of lost milk. The value here has been included in the calculation of the maintenance energy (ME) requirement.
% Forage: 60.7%
The comment behind the cell containing this label is shown in Figure 19-36.
Figure 19-36 This is the percentage of forage in the feed dry matter. It is one of the oldest ways of assessing effective fiber in the diet. The usual recommendation is that the ration should contain more than 40 percent forage.
Predicted rumen pH: 6.46
The comment behind the cell containing this label is shown in Figure 19-37.
Figure 19-37 Dry matter intake (DMI) begins to fluctuate at a ruminal pH below 6.2. At a ruminal pH below 6.0, the ability of bacteria to derive energy from forages declines. Note that although it is advisable to feed buffer to help manage ruminal pH on high-grain diets, buffer is not considered here in the ruminal pH prediction.
The Nutrient Concentration Display (strike F5)
The nutrients in the ration and the predicted nutrient targets are expressed in terms of concentration. That is, the nutrients provided by the ration are divided by the amount of ration dry matter and the nutrient targets are divided by the target amount of ration dry matter. Concentration units include percentage, milligrams per kilogram or parts per million, calories per pound, and international units per pound.
The comment behind the cell containing this label is shown in Figure 19-38.
Figure 19-38 Dietary Cation--Anion Difference (DCAD). DCAD is used to assess the impact of the ration's mineral content on the body's efforts to regulate blood pH. It can also be manipulated to prevent milk fever. Feeding anionic salts to dry cows for the 2 weeks prior to freshening reduces the DCAD, forcing cows to mobilize calcium. This prepares cows for early lactation in which they also must mobilize calcium. Because anionic salts are generally unpalatable, there is a risk that feed intake will be negatively impacted and, therefore, manipulation of DCAD should probably only be considered where milk fever is a significant problem. The equation used here is: (mEq (Ca_Mg_Na_K) - mEq (Cl + S+P))/kg DMI (Goff, J. 2000.) To prevent milk fever, a goal would be to achieve a -40 to 50 DCAD. The Goff reference is a personal communication reported in D. G. Fox, T. P. Tylutki, M. E. Van Amburgh, L. E. Chase, A. N. Pell, T. R. Overton, L. O. Tedeschi, C. N. Rasmussen, & V. M. Durbal. 2000. The Net Carbohydrate and Protein System for Evaluating Herd Nutrition and Nutrient Excretion, CNCPS version 4.0. Animal Science Department Mimeo 213. Cornell University.
The comment behind the cell containing this label is shown in Figure 19-39.
Figure 19-39 Calcium-to-phosphorus ratio. This ratio is of little significance if requirements for phosphorus and calcium are met. No differences in milk yield, persistency of milk production, milk composition, or reproductive performance were found in cows during early lactation fed diets with calcium to phosphorus ratios ranging from 1:1 to 8:1. Dairy NRC, 2001.
The comment behind the cell containing this label is shown in Figure 19-40.
Figure 19-40 The dietary nitrogen-to-sulfur ratio should be between 10:1 and 12:1 for efficient utilization of nonprotein nitrogen (urea). (Bouchard, R. and H. R. Conrad. 1973. J. Dairy Sci. 56, 1276-1282; Qi et al., 1993. J. Anim. Sci.). This is because the rumen microbes need a source of sulfur with nitrogen to synthesize the sulfur containing amino acids. This recommendation is based on total sulfur, not bioavailable sulfur. However, since most sulfur sources are 100 percent bioavailable, little error is incurred when using bioavailable sulfur. Nitrogen was calculated from crude protein using 16 percent as the average nitrogen content of protein. This ratio may be ignored if urea is not being fed.
LCT ([degrees]F) -39.46
The comment behind the cell containing this label is shown in Figure 19-41.
Figure 19-41 LCT (lower critical temperature) is calculated from body insulation and heat production. Since heat production is dependent upon the energy content of the ration, the LCT will change with the energy content of the ration. Animals in environments below the LCT are cold stressed and will use feed energy to maintain their body temperature, leaving fewer nutrients available for other functions.
Daily weight change, lb. (cows) 0.44
The comment behind the cell containing this label is shown in Figure 19-42.
Figure 19-42 This calculation is based on how the ration's energy status is affecting daily body weight change. If there is excess energy, the animal will be replenishing reserves and gaining weight; if there is an energy shortage, the animal will be mobilizing body fat and losing weight. For dry cows, this value should be within 20 percent of the target average daily gain (ADG). For close-up dry cows, which will be on the ration for only a short time, it may be acceptable to have a high predicted rate of gain because the goal is to prepare the rumen for the high-grain ration of a lactating group.
Days to gain 1 CS 471
The comment behind the cell containing this label is shown in Figure 19-43.
Figure 19-43 Based on whether dietary energy is deficient or in excess of requirement, the animal may be gaining or losing body weight. The value shown is the number of days to lose or gain enough body-fat reserves to change a BCS (5 point scale). To calculate what one BCS equates to in terms of pounds, multiply the days to gain/lose 1 BCS by the daily weight change. A cow's energy deficit should not be so deep that she is predicted to lose a BCS in less than 100 days. For close-up dry cows, see the comment under Daily weight change.
The Feedstuffs Contributions Display (strike F6)
Shown here are the nutrients contributed by each feedstuff in the ration. This display is useful in troubleshooting problems with nutrient excesses.
The Amino Acid Flows and Production Potentials Display (strike F7)
Shown here are the essential amino acids, their predicted flows to the small intestine, the percent of MP this represents, and the pounds of milk this could support. These calculations do not consider how shifting metabolic pathways affect amino acid supply and demand.
The Graphic Display
At the bottom of the home display are tabs. The current tab selected is the Worksheet tab. Other tabs are graphs based on the current ration. Note that you may have to click the leftmost navigation button at the lower-left corner to find the first tab.
Click on this tab to display a graph titled Nutrient Status: Dry Matter Intake
Click on this tab to display a graph titled Nutrient Status: Energy
Click on this tab to display a graph titled Sources of Metabolizable Protein (MP)
Click on this tab to display a graph titled Nutrient Status: Macrominerals
Click on this tab to display a graph titled Nutrient Status: Microminerals
Click on this tab to display a graph titled Nutrient Status: Vitamins A, D & E
Click on this tab to display a graph titled Nutrient Support for Milk Production
Click on the Worksheet tab.
Blend Feedstuffs Procedure
Click on the Blend Feedstuffs button. The note in Figure 19-44 displays.
Figure 19-44 YOU MUST HAVE ALREADY SELECTED THE FEEDSTUFFS YOU WANT TO BLEND. When your analysis is acceptable, strike ENTER and F3 to name and file the blend. NOTE: The formulas in this Workbook use measured protein digestion rates, %/hr (Kd), mineral bioavailability and fat, CP, RUP, NFC, & NDF digestibilities for individual feedstuffs. When a blend is made and used in a ration, the blend is "decomposed" and the characteristics of the blend's component feedstuffs are used. For this reason, DO NOT use one blend as a component of another blend.
We will plan on having one mineral/vitamin blend.
To the left of the feedstuff name, enter an amount of 0 for all ingredients except the mineral and vitamin sources as shown in Table 19-7.
Notice that as the amounts entered change in the gray area, a calculation is made of the appropriate pounds per ton in the blue area. Because feed mill mixers have capacities rated in tons, it is necessary that formulas to be mixed be expressed in pounds per ton.
Strike ENTER and F3. The input box in Figure 19-45 displays.
Figure 19-45 The name of this blend is BLEND1. This name is accessed in the application to assign nutrient value; therefore, the name must not be altered.
Click OK. The message box in Figure 19-46 displays.
Figure 19-46 The new blend has been filed at the bottom of the feed table. When used in a ration, the blend will be "decomposed" and the digestion characteristics of its component feedstuffs will be used in calculations.
View Blends Procedure
Click on the View Blends button to confirm that the BLEND1 formula and analysis have been filed. The note in Figure 19-47 displays.
Figure 19-47 Cursor down for more nutrients. DO NOT TYPE IN THE BLUE AREAS.
After viewing BLEND1, strike F1 to return to the home display.
Using the Blended Feed in the Balanced Ration
Select Feeds Procedure
Click on the Select Feeds button and select the feeds shown in Table 19-8. Unselect all other feedstuffs. Remember that the BLEND1 blend is located at the bottom of the feed table (row 200).
Strike ENTER and F2.
Make Ration Procedure
Click on the Make Ration button. Enter the ration shown in Table 19-9.
The amount of blood meal, soybean meal 49%, soybeans roasted, mixed grass/legume silage mid maturity, mixed grass/legume hay mid-maturity, corn grain ground, and corn silage have already been established. The amount of the BLEND1 to feed is the total amount of its component ingredients in the balanced ration. That value is:
0.25 + 0.000015 + 0.00062 + 0.03681 + 0.0000314 + 0.28 + 0.000023 + 0.02392 + 0.00848 + 0.02238 + 0.002 = 0.62 lb.
This value is recorded at View Blends under Formula, as entered. The ration is balanced as it was when the components of BLEND1 were fed unmixed.
Strike ENTER and F1.
Print Ration or Blend Procedure
Make sure your name is entered at cell C1.
Click on the Print Ration or Blend button. The input box in Figure 19-48 displays.
Figure 19-48 Are you printing a dairy ration evaluation or a blend formula and analysis? (1-RATION, 2 BLEND)
Click OK to accept the default input of 1. A two-page ration printout will be produced by the machine's default printer.
Click on the Print Ration or Blend button. This time enter a value of 2 to print a blend. Click OK. The message box shown in Figure 19-49 displays.
Figure 19-49 Click on the green number above the blend you want to print and press F4.
Find the blend named BLEND1. Click on the green number above it and strike F4. A one-page printout of the blend formula and analysis will be produced by the machine's default printer.
ACTIVITIES AND WHAT-IFS
In the Forms folder on the companion CD to this text is a DairyInput.doc file that may be used to collect the necessary inputs for use of the Dairy Ration.xls file. This form may be printed out and used during on-farm visits to assist in ration evaluation activities.
1. Remake the ration described in Table 19-5 for the lactating cow described in this chapter. Blend all feedstuffs. If there is not extensive sorting of the feed fed to the lactating cows, this blend represents the nutrient value of the refusals. Input a dry cow at 250 days pregnant. From the feed table, select the blend that represents the refusals. Meet the dry cow's DMI with the refusals blend. How many days are needed to gain a condition score for this dry cow? What problems might you expect due to this situation? What is the urea cost in this ration? Explain why this value indicates an excess of dietary protein.
2. Remake the ration described in Table 19-9 for the lactating cow described in this chapter. The answers to the following questions are found by striking F9. Given that metabolizable energy is used with similar efficiencies for the functions of maintenance and milk production, feed energy content is expressed as net energy for lactation (NEl) whether discussing maintenance or lactation energy needs. How many megacalories of NE1 are required to meet the maintenance needs of this cow? How many pounds of feed dry matter are needed to deliver this number of mega-calories? How many additional pounds of feed dry matter is this animal eating beyond that needed to supply maintenance energy? How many megacalories of NEl will these additional pounds provide? Given the megacalories of NE1 in one pound of milk as shown at F9, how many pounds of milk is the energy beyond maintenance in this ration capable of supporting? Based on the animal and environmental inputs, what is this cow's milk production potential? What is the difference between the pounds of milk that the energy content of the ration can support and the cow's milk production potential? How many megacalories of NE1 does this difference represent? Given the megacalories NEl per pound reserve change shown at F9, how many pounds of reserves will the cow replenish with the extra megacalories of NE1?
3. Remake the ration described in Table 19-9 for the lactating cow described in this chapter. What amount of milk is supported by the energy and protein levels of the ration? Strike F1 and click on Select Feeds. What is the digestible energy, Mcal/lb. of the corn silage? Change the NDF content for the corn silage from 45 to 35 percent. Strike ENTER and F10 to recalculate digestible energy and digestible NDF. What is the new digestible energy, Mcal/lb. for corn silage? Strike F2 to select this new corn silage. What are the new levels of milk supported by the ration? Back at the feed table, return the corn silage NDF to 45 percent. Strike ENTER and F10. In the mixed grass/legume silage, record the DE, Mcal/lb. and the digestibility of the NDF (NDFdig) lb./lb. Change the lignin percentage in the mixed grass/legume silage from 5.9 to 4 percent. Strike F10. What is the new NDFdig, lb./lb.? What is the new DE, Mcal/lb.? Strike F2 to select the new hay crop silage. What is the effect of this changed analysis on pounds of milk supported by the ration? Explain how changes in forage NDF and lignin affect digestible energy content and NDF digestibility.
Bouchard, R. & Conrad, H. R. (1973). Sulfur requirement of lactating dairy cows. I. Sulfur balance and dietary supplementation. Journal of Dairy Science. 56, 1276-1282.
Fox, D. G., Tylutki. T. P., Van Amburgh, M. E., Chase, L. E., Pell, A. N., Overton, T. R., Tedeschi, L. O., Rasmussen, C. N., & Durbal, V. M. (2000). The Net Carbohydrate and Protein System for Evaluating Herd Nutrition and Nutrient Excretion, CNCPS version 4.0. Animal Science Department Mimeo 213. Cornell University.
National Research Council. 1980. Mineral Tolerance of Domestic Animals. Washington DC: National Academy Press.
National Research Council. 1987. Vitamin Tolerance of Animals. Washington DC: National Academy Press.
Qi, K., Lu, C. D., & Owens, F. N. (1993). Sulfate supplementation of growing goats: effects on performance, acid-base balance, and nutrient digestibilities. Journal of Animal Science. 71, 1579-1587.
Table 19-1 Animal inputs for the dairy ration formulation example 65 Age (months). If a lactating animal was chosen, this entry must be >21 months. 1400 Body weight (lb.) no Ionophore inclusion (yes/no) 70 Days pregnant. For dry cows, this value should be 220-282. For heifers < 55% mature weight, this value should be 0 3 Condition Score (1-5) 150 Days in milk (DIM). DIM should be greater than the number of days pregnant by the number of days past calving that you wait to rebreed. 24 Age at first calving (months) 12 Calving interval (months) 4 Breed (1--Ayrshire, 2--Brown Swiss, 3--Guernsey, 4--Holstein, Jersey, 6--Milking Shorthorn) 3.5 Milk fat (%) 3.3 Milk protein (% true protein) 4.8 Milk lactose (%) 12 Milk price, dollars per cwt (100 lb.) 24,000 Rolling herd average (used with lactation # to create a lactation curve for the herd) 3 Lactation # (used with rolling herd average to create a lactation curve for the herd) Table 19-2 Body condition score descriptions for dairy cattle BCS 1 2 Tailhead Deep cavity Shallow cavity Pelvic bones Sharp and easily Prominent and easily felt felt Processes of Distinct, giving a Ends rounded, upper lumbar sawtooth surfaces felt with vertebrae appearance slight pressure Area between Deep depression Depression still processes of obvious lumbar vertebrae BCS 3 4 Tailhead No cavity Folds of fat Pelvic bones Smooth but felt Rounded but felt with pressure with firm pressure Processes of Fat covering upper Cannot be felt lumbar surfaces but still vertebrae felt with pressure Area between Slight depression Nearly flat across processes of back lumbar vertebrae BCS 5 Tailhead Buried in fat Pelvic bones Cannot be felt Processes of Rounded and lumbar covered vertebrae with fat Area between Rounded processes of lumbar vertebrae Table 19-3 Environmental inputs for the dairy ration formulation example 60 Current temperature ([degrees]F) 60 Temperature average for the previous month ([degrees]F) 1 Wind speed (mph) no Grazing (yes/no) N/A N/A N/A 0.3 Hair depth, inches (in.) 2 Coat condition (1--clean/dry, 2--some shud on legs, 3--shud on lower body, 4--covered with shud) 1 Heat stress unlikely--input should probably be 1 (see comment) Yes Is there significant relief from the heat at night? (Heat stress unlikely--input should probably be yes.) Table 19-4 Feedstuffs to select for the dairy ration formulation example Blood meal, flash dried Soybean meal, 49% Soybeans, roasted Mixed grass/legume silage, mid maturity Mixed grass/legume hay, mid maturity Corn grain, ground Corn silage, normal Calcium carbonate Cobalt carbonate Copper sulfate Dicalcium phosphate EDDI (Ethylenediamine dihydroiodide) Salt (sodium chloride) Sodium selenite Vitamin A supplement Vitamin D supplement Vitamin E supplement Zinc oxide Table 19-5 Inclusion rates for feedstuffs in the dairy ration formulation example Blood meal, flash dried 0.2 Soybean meal, 49% 5.5 Soybeans, roasted 1.5 Mixed grass/legume silage, mid maturity 38 Mixed grass/legume hay, mid maturity 3 Corn grain, ground 16 Corn silage, normal 38 Calcium carbonate 0.25 Cobalt carbonate 0.000015 Copper sulfate 0.00062 Dicalcium phosphate 0.03681 EDDI (Ethylenediamine dihydroiodide) 0.0000314 Salt (sodium chloride) 0.28 Sodium selenite 0.0000237 Vitamin A supplement 0.02392 Vitamin D supplement 0.00848 Vitamin E supplement 0.02238 Zinc oxide 0.002 Table 19-6 Upper limits for ration nutrients used in the dairy ration application. Upper Limit DMI 6% over predicted requirement Energy No upper limit. Excess beyond maintenance is used to predict performance. Metabolizable protein No upper limit. Excess beyond maintenance is used to predict performance. Calcium--bioavailable 2% of diet dry matter Phosphorus--bioavailable 1% Magnesium--bioavailable 0.5% Potassium--bioavailable 3% Sulfur--bioavailable 0.4% Sodium--bioavailable 1.6% lactating, 3.5% nonlactating Chloride--bioavailable 2.5 lactating, 5.5% nonlactating Iron--bioavailable 1000 mg/kg or ppm Manganese--bioavailable 1000 mg/kg or ppm Copper--bioavailable 100 mg/kg or ppm Zinc--bioavailable 500 mg/kg or ppm Iodine--bioavailable 50 mg/kg or ppm Cobalt--bioavailable 10 mg/kg or ppm Selenium--bioavailable 2 mg/kg or ppm Vitamin A 30 times the requirement Vitamin D 4 times the requirement Vitamin E 20 times the requirement Source DMI Author Energy Metabolizable protein Calcium--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Phosphorus--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Magnesium--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Potassium--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Sulfur--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980) Sodium--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle, based on limit for salt (sodium chloride) Chloride--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle, based on limit for salt (sodium chloride) Iron--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Manganese--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Copper--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Zinc--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Iodine--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Cobalt--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980)--cattle Selenium--bioavailable NRC:Mineral Tolerance of Domestic Animals (1980) Vitamin A NRC:Vitamin Tolerance of Animals (1987) Vitamin D NRC:Vitamin Tolerance of Animals (1987) Vitamin E NRC:Vitamin Tolerance of Animals (1987) Table 19-7 Inclusion rates for feedstuffs in the dairy MinVit blend Blood meal, flash dried 0 Soybean meal, 49% 0 Soybeans, roasted 0 Mixed grass/legume silage mid maturity 0 Mixed grass/legume hay mid maturity 0 Corn grain, ground 0 Corn silage, normal 0 Calcium carbonate 0.25 Cobalt carbonate 0.000015 Copper sulfate 0.00062 Dicalcium phosphate 0.03681 EDDI (Ethylenediamine dihydroiodide) 0.0000314 Salt (sodium chloride) 0.28 Sodium selenite 0.0000237 Vitamin A supplement 0.02392 Vitamin D supplement 0.00848 Vitamin E supplement 0.02238 Zinc oxide 0.002 Table 19-8 Feedstuffs and blend to select for the dairy ration formulation example Blood meal, flash dried Soybean meal, 49% Soybeans, roasted Mixed grass/legume silage, mid maturity Mixed grass/legume hay, mid maturity Corn grain, ground Corn silage normal BLEND1 Table 19-9 Feeding rates for feedstuffs and blend in the dairy ration formulation example Blood meal, flash dried 0.2 Soybean meal, 49% 5.5 Soybeans, roasted 1.5 Mixed grass/legume silage, mid maturity 38 Mixed grass/legume hay, mid maturity 3 Corn grain, ground 16 Corn silage, normal 38 BLEND1 0.62
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|Author:||Tish, David A.|
|Publication:||Animal Feeds, Feeding and Nutrition, and Ration Evaluation|
|Date:||Jan 1, 2006|
|Previous Article:||Chapter 18 Feeding dairy.|
|Next Article:||Chapter 20 Feeding sheep.|