Our practice publishes an annual benchmarking spreadsheet with data from freestall herds. We have saved spreadsheets going back to 2004. We do not always collect the same data each year, so we cannot go all the way back to 2004 to look for progress in every area, but the data we have clearly shows our cows are healthier today and more productive. Here are some specific measures:
    – Percent calves born DOA: This peaked at 10.8% in 2007, but has been trending down ever since. In our 2020 survey, only 4% of calves were born dead, for a drop of 63%. This is remarkable progress, for which the reasons are not totally clear. Producers are likely doing a better job observing calving and managing cows in prefresh and calving pens. Twinning rates have dropped a lot as well, so this might explain some of the reduced DOAs. Genetic selection against animals with higher DOA rates also probably plays a part.
    – Twinning: In 2004, the average was 7.1%, while in 2020 it was down to 3.7%. What caused this? Again, we do not really know, but there are two likely possibilities. One, more herds in our practice use the double ovsynch breeding protocol today, and we know it can reduce twinning rates. Two, reproductive performance has improved greatly over the same period, and some of this is due to better management of body condition loss. Twins commonly occur in cows that have low progesterone at the time of follicular development, and cows losing weight are likely to have low progesterone.
    – Displaced abomasum: 7.3% of fresh cows had a DA in 2004. Only 2% did so in 2020. This is a drop of 73%, making displaced abomasum an uncommon event on many dairies today. This is most likely due to better dry cow, prefresh cow and fresh cow management.
    – Retained placenta: In 2007, the rate of fresh cows with RP was 9.3%, and in 2020, it was only 3%, for a drop of 68%. Most likely this is due to better dry cow and prefresh cow management. Retained placentas are also becoming unusual on well managed dairies.
    – Dead cows: This peaked at 7.3% in 2007. For 2020, dead cows dropped 40% to 4.4%. This is calculated by dividing total dead cows by average lactating and dry cow herd size. This is great progress and an impressively low death rate.
    – Reproduction: Back in 2004, the average pregnancy rate was 18%, and the average conception rate was 33.9%. In 2020, the pregnancy rate was 29%, and the conception rate was 46%. Almost all the gain in pregnancy rates is due to better conception rates, not better service rates. An overall conception rate of 46% for all breedings, in herds that averaged 91 pounds of energy corrected milk, seems remarkable. Better conception rates are due to better nutrition, better breeding protocols and compliance, better control of body condition, better fresh cow health and more.
    – Culling rates: Culling rates have recently come down from a high of about 40% in 2011 to 37% in 2020. However, back in 2004 culling was only 32%. Most likely culling increased as reproduction and calf survival improved. Farmers created a whole lot more replacements and kept them alive. The average age of cows in the herd peaked in 2008 at 48.4 months, and then slowly declined to 44.3 months in 2018. Only in the last two years have we seen ages start to creep back up reaching 47 months in 2020. Percentage of herd in first lactation was 41% as recently as 2018, but dropped to 36% for 2020. Many farmers are now raising fewer heifers and trying to increase the average age of the herd by lowering the percentage of herd as first lactation. Heifer supplies have shrunk. In 2020, the average ratio of replacements to total cows, lactating and dry was 91%. As recently as 2016 it was 103%. As these smaller heifer herds calve, farmers will be forced to cull fewer cows. This will create a number of management challenges, because while older cows do give more milk, they have greater rates of some problems, including mastitis and reproductive failure.
    – Production: Herds averaged 85 pounds of milk, 91 pounds of energy corrected milk, and 6.06 pounds of fat and protein per cow in the 2020 data set. Milk production peaked in 2016, at 89 pounds, but energy corrected milk today is just one-half pound below 2016’s 91.5 pounds. So, at least for production of components, producers seem to have caught up to the days of rBST use.
    While our data set is far from perfect, it is good enough to evaluate trends, and it is clear that cows are healthier today, in spite of continued increases in productivity. This is something for our industry to be proud of, so give yourself a pat on the back. Great work everyone.
    Bennett is one of four dairy veterinarians at Northern Valley Dairy Production Medicine Center in Plainview, Minn. He also consults on dairy farms in other states. He and his wife, Pam, have four children. Jim can be reached at bennettnvac@gmail.com with comments or questions.