DairyComp 305 (DC305) is an important management tool for producers to collect herd data for use in monitoring performance.

One useful application for the program is to extract a Week 4 Milk average, an item which allows the user to quickly evaluate the effectiveness of the transition period. These data points can then be displayed graphically in order to demonstrate trends and variation in fresh cow performance, which the herd management team can then use to determine the causes for any performance changes.

The DC305 Week 4 Milk calculation has multiple benefits:

• Current results

Because the calculation involves little lag time, it shows how cows that recently entered the fresh group are performing.

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• Early lactation production

Early lactation milk yield is a good predictor of expected milk production throughout the lactation, which means evaluating early performance can indicate future profitability. It will also help identify potential problem cows.

• Easily identify herd trends

By identifying negative trends early you can make slight adjustments rather than react with drastic changes after production has begun to drop significantly.

Many producers use first-test-day milk production to assess early lactation performance, but test-day weights can be taken anywhere within the first seven to 45 days in milk (DIM). Week 4 Milk aligns all animals on a level playing field to allow for comparison between animals and groups of animals. The newest version of DC305 has Week 4 Milk as a preset item; either make sure you have a current version or consult the sidebar on page 48 to create an item to retrieve the data in your DC305 program. If you use another computer program to monitor herd performance, consult your software representative to set up a similar calculation within your system.

Evaluating Week 4 Milk graphs

With the calculation set up in your DC305 program, graphs can be generated to visually display cow performance four weeks postpartum. To more effectively use the Week 4 Milk data, break it out by lactation to identify trends and track each group of cows.

Figure 1 is an example of Week 4 Milk over a one-year period. The “Y”, or vertical axis, accounts for the pounds of milk produced during Week 4 and the “X”, or horizontal axis, is the date. As you will see, over time Week 4 Milk has decreased slightly according to this herd’s fresh cow records. The trend is shown by the blue regression line, which signifies the herd’s Week 4 Milk production average.

Figure 2 shows a positive trend in Week 4 Milk production over the one-year time frame. This can be related to nutrition, facility design, season or a myriad of other management-related areas.

Week 4 Milk can also identify variation within the group being evaluated. If animals are performing well below average, we must ask ourselves why. Figure 3 (page 48) is an example of such a situation as the number of animals performing below their potential in the first six months is 10, while the number jumped to 47 during the second six-month period. Identifying such trends is the first step to making the appropriate changes to your prefresh and fresh cow programs.

Making improvements from Week 4 Milk findings

Week 4 Milk graphs can provide producers with an indication that management changes are needed to improve fresh cow performance. When Week 4 Milk has declined or variation has increased, the first question to ask is: “What is limiting dry matter intake?” Investigate the following five areas when looking to identify potential problem areas:

Ration changes

Changes in forage and feed ingredient quality can quickly alter milk production and fresh cow performance. Especially at a time when consistency is particularly important, the ration must provide the right balance of energy, protein, fiber and macrominerals for a smooth transition into the milking string.

Seasonal impact

It’s important to keep cows cool and healthy during summertime heat, as a drop in milk production is not often regained after the hot weather subsides. Especially in the fresh cow pen, where peak production has not yet been reached, maximizing milk produced over the complete lactation is critical. In colder months ensure animals are kept dry, out of the wind and supplied a fresh, high-quality ration to successfully navigate brutal winter weather conditions.

Cow comfort

Minimize overcrowding and movement in the close-up and fresh cow pens to ensure each cow has adequate feedbunk space and room to lie down.

General transition health

Review on-farm procedures with staff and consult your veterinarian about current vaccination protocols. It is common for animals performing below the group average postpartum to be experiencing a metabolic disorder, having trouble cleaning or going off feed.

Heifer development and condition

Underdeveloped or overconditioned heifers often have lower start-up milk production. Work with your nutritionist to ensure heifers are reaching the milking string at the appropriate size and in a timely fashion.

While Week 4 Milk is a simple DC305 tool to use and monitor, no calculation can replace the importance of actually taking time to watch fresh cows. Spend time watching cows in their environment to ensure each animal is comfortable, receives adequate levels of high-quality feed and is not stressed.

Use Week 4 Milk as an indicator of performance to identify potential challenges to the transition program. Used as one tool within a full management program, Week 4 Milk may shed further light on fresh cow performance, allowing each animal to perform to its potential. PD

Gene Boomer

Technical Services

Arm & Hammer Animal Nutrition

gene.boomer@churchdwight.com

How to set up Week 4 Milk in your DairyComp 305 program

1. Go to your ALTER menu, which can be done by typing “alter” on the command line.

2. Click on the “add” button to create a new item. This will create a new item within DC305.

3. Assign “Week 4 Milk” a name. “W4MK” is commonly used, but feel free to adjust the name to another code that is five characters or less. Hit “okay” once the name of the item is entered.

4. Tell DC305 what is to be measured. In this case select “Weekly average on week X,” which is item #122. You can select #122 from the drop-down box or type in “122” in the box. Once you have the proper one highlighted, hit enter.

5. Now define “X.” Since week 4 is “X”, place a “4” in the value box.

6. Enter measurement description on the next screen. The description can be “Week 4 Milk Production.”

7. The next screen will ask if you want to save this new category. Hit “Yes” and Week 4 Milk has been created.

8. With the new category created, define what is to be measured. An example command line for second-lactation animals is below:

GRAPH W4MK FOR LACT=2 FDAT>-365\RL BY FDAT

• “LACT” is the lactation number being pulled up in the chart. This equation accounts for second-lactation animals, but this value can be changed for different groups.

• By using “FDAT>-365”, DC305 will go back 12 months within the herd.

• “R” requests the regression line to be created within the graph.

• “L” asks DC305 to include all cows in the data.

NOTE: This calculation is for the DairyComp 305 software program. If you are using a different program, work with your software representative to set up a similar calculation.