December 28, 2017
Listen in on this ‘Big Fat Idea’ on how to gain a clearer picture of start-up milk using weekly milk lactation plots. Renee Smith from Virtus Nutrition gives a great overview of how this weekly milk view can help:
For the last 20 years Renee Smith, California Sales Manager for Virtus Nutrition, has been working with dairy producers to improve overall cow health and productivity. One of her top priorities is to focus in on what matters most: monitoring fresh cow performance since the start of the lactation really determines the rest of the lactation.
“Producers and nutritionists are bombarded with an incredible number of tools, from feed supplements to vaccines and other therapies. When they choose to make one of those changes, start-up milk is often the most visible way to see tangible improvement,” added Smith.
The most common ways to look at start-up performance all have their own challenges. Week 4 milk has been one of the best measures, but because of how it is calculated there is a 2 month lag in seeing the results. Similarly, 2nd test 305 ME projection has significant lag, and relies on estimates to project her future performance.
To see start-up milk clearly, Dairy Comp has a ‘PLOT’ command that plots weekly milk (wmlk1 item) over the lactation which gives you a visual of how cows are starting up over time vs. other cohort groups. The weekly milk item already exists for daily milk weight herds, as that is a roll-up of their daily milk weights. For monthly test day herds, the weekly milk is an estimation based on their test day data, which is similar to how week 4 is calculated but some of that lag time is removed. These commands can be run by stage of lactation, by month fresh, or by plotting individual cows that are on a trial. To download the PDF with instructions on how to run these milk charts click here.
Since there can be variation in the percent of 1st lactation vs. older cows, Smith suggests running the weekly milk reports by lactation group to give the most accurate comparison. Also, pay attention to seasonal impacts, as hot summer months will impact the lactation curve.
Overall, monitoring fresh cow performance is critical for quickly seeing changes in herd performance, since the start of the lactation determines the rest of the lactation.
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