The “Cow Value” module in Dairy Comp 305 estimates the value of each cow in a dairy herd relative to an average fresh heifer. A positive Cow Value means the animal is worth more than an average heifer in that herd. A negative Cow Value suggests the animal is worth less than an average heifer. In addition to estimating the value of the cow, the module also calculates the current value of a pregnancy for each adult, to help managers decide if an open animal should be inseminated.
Dairy Comp 305 includes a powerful tool that can help dairy herd managers decide to breed, treat, or cull animals on a daily basis. This module is called Cow Value.
There are two important rules to remember when using the Cow Value estimates.
1. Keep your dairy at capacity.
less profitable animals with more profitable animals.
Replace less profitable animals with more profitable animals.
Every decision made on an animal in a commercial dairy is based on improving the herd’s profitability. You keep an animal because she is more profitable to keep than to replace. You breed animals because they will be more profitable if they become pregnant. You treat animals because they will be more valuable after a treatment than they are before. Cow Value estimates can help the herd manager assign a value to animals more consistently.
A commercial dairy cow’s current value is the sum of her value for beef and the value of the milk she is likely to produce in the future.
The value of an animal’s future production is based on
· The amount of milk she is likely to produce in the future.
· The price of milk in the future.
· The value of the money you must invest in the animal.
The amount of milk an animal is likely to produce in the future is based on
· Age –The younger the animal, the longer she is likely to stay in the herd and produce milk.
· Stage of lactation - an animal that is 30 days in milk is likely to produce more milk in the future than an animal that is 200 days in milk
· Reproductive status - an animal that is pregnant is likely to produce more future milk, than an animal that is open. An animal that was just inseminated, is more likely to be pregnant than an animal that has not been inseminated.
· Production level - a high producing animal is likely to produce more milk than a low producing animal.
A) Start Cow Value by typing COWVAL on the command line in Dairy Comp.
· Allow Dairy Comp to make the two new items, CWVAL and PGVAL
· Have Dairy Comp estimate the values
B) Make lists of animals to get a feel for how it ranks and values your cows.
· Change some of your assumptions and re-run the lists. Note how the values changed.
C) Put the CWVAL and PGVAL on your cow cards, and perhaps your vet list.
See Appendix A.
D) Set the scheduler to re-calculate CWVAL and PGVAL each night so the values will stay current. See Appendix B.
Run the Cow Value module.
Go to the command line in Dairy Comp and type COWVAL <enter>
A menu appears with the following choices:
1) Exit - Enter 1 to exit Cow Value
2) Edit Parameters - Change parameters
3) Estimate Cow Value - Calculate Cow Value
4) Calculate Parameter Estimates - Use to calculate parameters from
Select 2 – Edit Parameters
This table appears.
Lact 1 CullRate 0.20
Lact 2 CullRate 0.30
Lact 3 CullRate 0.45
Pregnancy Rate 0.14 Lact 4 CullRate 0.55
Conception Rate 0.40 Lact 5 CullRate 0.65
Heat Detection 0.35 Lact 6 CullRate 0.70
Lact 7 CullRate 0.75
VWP 60 Lact 8 CullRate 0.80
Avg Dopn 130 Lact 9 CullRate 0.90
Heifer Cost 1200 Lact 1 305 Milk 20000
Cull Value 300 Lact 2 305 Milk 22000
Lact 3 305 Milk 24000
Milk Price/cwt 13.00
Marginal Feed 3.00 Lact 1 Persist 0.96
Maint Feed/day 1.50 Lact 2 Persist 0.94
Lact 3 Persist 0.92
Discount Rate 0.10
These parameters are discussed in more detail in Appendix C, and a descriptive text appears when the value is highlighted and the F1 key is pressed.
You can return to the Cow Value menu by pressing the escape (ESC) key. The menu option "Calculate Parameter Estimates" will use cow data from your cowfile to estimate the culling rates and the 305 day milk production averages. Warning: estimates based on past performance often do not accurately project future performance.
Once you have reviewed the parameters press escape and select “estimate Cow Value” from the menu.
The first time Dairy Comp estimates Cow Value it will ask you to allow it to create two new items, first CWVAL (to store the Cow Value estimate) and then PGVAL (to store the value of a pregnancy). Press <enter> each time Dairy Comp asks if you would like to create the two new items. If Dairy Comp warns you that your Item Table is full, call the dairy management support group for help. Dial 1-800-496-3344 and press 3.
A brief summary is displayed following the calculation of Cow Value.
Cull Milk 49 <-- Cutoff pounds of milk for DNB cows
Replacement 800 <-- Cash cost of replacement (Heifer
cost – beef value of cull)
Heifers 0 <-- Number of heifers - ignore
To Sell 65 <-- Number with negative cow value
To Keep 568 <-- Number with positive cow value
Average CWVAL 705 <-- Average value of all cows
Open 277 <-- Number of open cows
Average PGVAL 178 <-- Increased value if an average
open animal becomes pregnant
Preg 356 <-- Number of pregnant cows
Average PGVAL 662 <-- Decreased value if an average
pregnant animal aborts
After calculating Cow Value exit the Cow Value routine by pressing the escape (ESC) key.
Make a report to look at the values
There are many different ways you may want to look at CWVAL and PGVAL. A simple start is to list all adults sorted by CWVAL. The lowest value animals will be on the top of the list. The highest value animals will be on the bottom of the list.
There are several different “FOR” statements to consider in your report. In this example report, we used “FOR DIM>75”. This narrows our cow list to those with more reliable production estimates for this lactation. It also excludes lactation zero animals. Once you get to know Cow Value estimates more, you may want to limit the list to cull candidates by using “FOR CWVAL<0”.
CWVAL and PGVAL Relative to Reproductive Status
· If an animal is not pregnant, than the value of getting her pregnant would be her current PGVAL. (If she became pregnant today her new CWVAL would be her current CWVAL plus her current PGVAL).
· If the animal is pregnant her CWVAL already includes her PGVAL. If she were to abort then her CWVAL would decrease by the PGVAL.
· If the animal is open and becomes bred her CWVAL goes up because she is more likely to be pregnant than before she was bred so she is more likely to produce more milk into the future.
A Simple Example Cow Value List
SHOW ID LACT DIM MILK RV RPRO DSLH DCC CWVAL PGVAL BY CWVAL FOR DIM>75
ID LACT DIM MILK RV RPRO DSLH DCC CWVAL PGVAL
===== ==== ===== ==== === ======= ===== ===== ====== ======
4224 3 84 26 59 BRED 11 0 -757 -248
1430 3 85 45 70 BRED 53 0 -646 157
6848 1 125 48 72 BRED 27 0 -410 587
32 3 457 47 114 NO BRED 0 0 -330 449
993 3 209 14 85 BRED 16 0 -330 -325
Animal 4224 is the least valuable animal in this herd. Her CWVAL is -$757 relative to an average springing heifer in this dairy. Further, If she were to get pregnant her value to this herd would decrease another $248 because she may be kept another lactation rather than be replaced with a more profitable animal. This suggests that the dairy will make more money, beginning today, if this animal is replaced with an average, fresh, first lactation animal.
Animal 6848 has a negative CWVAL but her PGVAL tells us that if she turns out to be pregnant to this current breeding (27 days ago) her value will become +$587 + (-$410) = +$147. She will become $147 more valuable than an average fresh heifer in this herd.
Animal 32 has been coded not to breed. The CWVAL shows that she should be replaced and the PGVAL tells us that she would have been $449 more valuable had she gotten pregnant earlier in this lactation.
--- Middle of report deleted ----
The end of the Cow Value report
ID LACT DIM MILK RV RPRO DSLH DCC CWVAL PGVAL
===== ==== ===== ==== === ======= ===== ===== ====== ======
5413 1 484 0 120 DRY 335 274 1782 2789
2579 1 465 79 130 PREG 127 131 1791 1359
2699 1 332 0 136 DRY 246 246 1814 2821
5324 1 343 82 135 PREG 123 91 1912 1426
This report lists the most valuable animals at the end. Animal 5324 wins. Notice that if she aborts her value will drop from $1912 to $486 ($1912-$1426). If 2699 aborts her value will drop from $1814 to –$1007 and she should be sold.
Key to the Report Headings
ID Cow ID number
LACT Lactation number
DIM Days in milk
MILK Last test day milk weight
RV Relative value (internal)
RPRO Repro code (FRESH,BRED,DRY etc)
DSLH Days since last breeding
DCC Days carried calf if pregnant
CWVAL estimate of cow
PGVAL estimate of value of pregnancy
From the Author, Dr. Steven Eicker, DVM
The future value of a cow is of course, unknown. This module is based on models that estimate the future profitability of a cow based on the parameters listed above. But certainly, pregnant cows are much more likely to remain in the herd, and higher producing cows are more likely to be more profitable next lactation too. Thus, these predictions should be used as guidelines. They are not meant to replace sound judgement, but to augment it.
The value of a cow is always relative to that of a replacement heifer.
Thus, a cow with a negative value is a potential cull. A cow with a
value of $150 that is diagnosed with a displaced abomasum may be more profitable shipped than treated.
The estimated value of a pregnancy can assist a dairy in deciding whether it is worth the effort to breed a cow. Likewise, for a pregnant cow, the pregnancy value can help estimate the cost of an abortion. Open cows with negative pregnancy values should not be bred, as spending money on pregnancy will lower their value!
Perhaps the most thought provoking concept arises when an open cow has a negative cow value, and also has a negative pregnancy value. This means she is worth less pregnant that if she remains open. However, the software algorithm assumes that cows that are not coded DNB are still trying to get pregnant, and that a percentage of the time they will. Thus, this cow will have a lower cow value while she is still eligible to be breed. Her value should INCREASE once she is flagged as a DNB. This makes sense - it is sometimes a profitable decision to flag a cow as a DNB cow. Note that a cow flagged as DNB may still have a positive cow value, until her milk production decreases below that cull/cutoff value.
By necessity, we are modeling the future to predict the future production of each cow. We make lots of assumptions, such as eventually, all cows leave the dairy, and when they do, a replacement enters the herd. Crucial to the model is that a dairy farm will operate to maximize profitability. Again, DNB cows demonstrate some of the fundamental concepts.
Flagging a cow DNB means she will not freshen again. It means that she will be sold once her milk production is "too low". What does "too low" mean? Two possibilities:
1. Her feed cost exceeds her income, somewhere around 20 pounds.
2. Her daily profit is less than a replacement, even including the
cost ($1/day) of the replacement, somewhere around 50 pounds.
Assuming a dairy is trying to make a profit, the correct decision is #2. The model sells cows once they produce less than this "Cutoff" milk. Let's say cutoff milk is 50#. A cow producing 60 pounds is profitable until she reaches 50 pounds, about two more months. Her expected production is about 55 for 60 days, which generates about 60 * (55-50) = 300# or $30 more than the heifer. Fine, her CWVAL will be about $30.
Adding CWVAL and PGVAL to your Cow Card display
Go to an animal’s cowcards and select two spots you would like to display the CWVAL and PGVAL estimates.
· “Right click” on the space on the cowcard you wish to display the Item.
· “Left click” on add\replace an item on the page.
· “Left click on the Item from the Item pick list that is displayed.
Once you have placed the items on a cow card, press ESC to exit Alter. Go to an animal’s cow card and confirm that the items are displayed.
Automatically updating Cow Value every day using the Dairy Comp Task Scheduler.
Animals’ values change daily. The calculation must be re-run each day for the estimate to remain current.
Under the File Menu select Alter.
· Select 6) Schedule Tasks.
· From the Task Scheduler Menu, select 4) Add a new task.
· When it asks for the next date to run, select tomorrow’s date.
· Schedule the next time for 0100, (1:00 AM).
· The Interval Unit will be Days.
· The interval will be 1, meaning every 1 day.
· The command to run is COWVAL\G.
Now the first time Dairy Comp is running idle in the foreground after 1:00 AM tomorrow, and each successive day, it will recalculate the Cowvalue estimates.
Add CWVAL and PGVAL to your vet list
One of the best times to decide to stop breeding an animal is when the veterinarian declares her open at a pregnancy exam. Having the value estimates on the vet list may make it easier to make that decision more consistently.
It the items will fit into your VITEMS command, it will be easy to add them. If they do not fit, or you would like help putting these estimates on the vet list
Heat Detection Rate is the ratio of heats observed to heats occurred
Conception Rate is the ratio of conceptions to breedings
Most dairies have heat detection rates between 0.35
and 0.75 and conception rates between 0.20 and 0.50
Pregnancy Rate is automatically calculated as the product of heat detection and conception rates. It can be interpreted as the percentage of heats that result in a pregnancy.
Voluntary Wait Period is the number of days in milk at which animals in heat will be bred.
Average Days Open is the average days in milk at conception.
Heifer Cost is the cost to either raise or purchase a replacement heifer.
If a significant percentage of heifers die, consider
adding that percentage to the purchase price.
Cull Price is the average expected income from selling a cow.
The difference between Heifer Cost and Cull Price is the cash expense of replacing a cow.
Milk Price is the expected milk price over the next few years per 100 units (pounds) of milk.
Marginal Feed is the estimated cost of the incremental feed required to get this additional milk. A quick estimate is the cost of 40 units (pounds) of dry matter.
Maintenance Cost is the daily feed expense to feed a cow not including milk production. A quick estimate is the daily cost to feed a dry cow, or a springing heifer.
Discount Rate is the expected annual return a dairy should get on money invested today. It is usually slightly higher than the current interest rate.
Cull Rate is the percent of cows that do not reach the next lactation.
The defaults are .20, .30, .45, .55, .65, .70, .75, .75, ...
Most dairies cull between .20 to .55 per lactation. This number tends to increase with age. Dairies with excellent reproduction and low calf losses can approach .50 unless they market springing heifers.
305 Milk is the predicted average 305 day milk production for each lactation.
Persistency is the estimated monthly change in milk production once a cow is past her peak production. The default values are as follows:
Lact 1 0.96
Lact 2 0.94
Lact 3+ 0.92