Cull rates are one of the bellwethers of herd health.
However, herd health and dairy cow removal aren't the only factor that drives cull rates . . . the inventory of herd replacements, future dairy cows, also drive cull rates.
So, what is the answer to a reader's question, "What is the cull rate in the United States?"
To give a somewhat concrete response to that question, we will dig into two USDA data sets: Milk Production and Livestock Slaughter. To remove fluctuations due to holidays and other monthly events, we will look at annual numbers found in the February 19, 2016, issue of Milk Production and the January 21, 2016, issue of Livestock Slaughter.
First, let's document dairy cow inventory published in Milk Production:
In 2015, there were 9,317,000 dairy cows in the United States.
In 2014, there were 9,257,000 dairy cows in the United States.
Next, let's document culled dairy cows published in Livestock Slaughter:
In 2015, there were 2,914,100 dairy cows sent to slaughter in the United States.
In 2014, there were 2,815,600 dairy cows sent to slaughter in the United States.
Now for a little division:
For 2015, we divide the 2,914,100 cows culled by the 9,317,000 dairy cow inventory.
That yields a cull rate of 31.28 percent.
For 2014, we divide the 2,815,600 cows culled by the 9,257,000 dairy cow inventory.
That yields a cull rate of 30.42 percent.
Those culls rates from the past two years - 31.28 and 30.42 percent - fall into ranges from many other studies.
As we alluded to earlier, cull rates vary throughout the world.
In the U.S., nearly every dairy cow gets bred to dairy semen to give birth to a dairy calf. That means the pipeline is rather full of dairy replacements. In some European countries, a greater share of lower-end dairy cows actually get bred to beef breeds to deliver calves solely destined for meat production. That is one reason cull rates in many European countries are lower than in the United States.
July 11, 2016