Culling: Fill Each ‘Cow Slot’ With Most Productive Animal

By Ron Johnson, Dairy Editor
Thursday, February 7, 2008 1:40 PM CST

To cull or not to cull? It’s a never-ending question for dairy producers.

One way to attack it is to break the problem down into the number of cow “slots” a dairy farm has, says Steve Eicker, a veterinarian with Valley Agricultural Software. Eicker talked about culling during last week’s Dairy Business Association (DBA) Expansion Symposium in Green Bay.

Each farm has an ideal number of cow slots, according to Eicker. If a barn has 50 stanchions or 50 tie stalls, the ideal number of slots could be 50. But often figuring out the best number of cow slots is nowhere near that simple.

“Freestalls and drylots are often overfilled, and some farms switch cows in stanchions. The optimum number of slots depends at least on management, parlor and labor capacity, the feeding system, and probably on the season,” Eicker said. “Every dairy should first work to determine its unique capacity and fill each slot with a productive cow.”

What if you leave a cow slot empty? That is “very expensive,” Eicker said.

“In the U.S., even in the face of very high prices for replacement animals, it is still profitable to purchase additional cows and fill the barn,” he said.

Eicker offered an example that used a cow producing 24,000 pounds of milk a year, with the milk worth $18 per hundredweight. After subtracting all the costs associated with adding that cow, she provided $1,537 in profit per year. That means, leaving a slot open, using the above numbers, costs a farm $1,537.

“Once all productive slots are filled, the goal of a culling decision is to fill each slot with the cow that will make the dairy as profitable as possible,” Eicker explained. “The profitability of a particular cow depends on many factors.”

They include the cow, how well she is milking, her health status, and her potential. Add into the equation the “profit potential” of whichever heifer will replace her.

“The goal of culling,” Eicker asserted, “is not to maximize the profit earned by a particular cow, but rather the profit earned by a slot on the dairy.”

Imagine an ideal world. In that ideal world, said Eicker, on any given day, a farmer or herd manager should consider every cow slot and ask one question. That question is: “Is the value this slot brings to the dairy greater if I leave the current cow in the slot, or would the value of the slot be greater if she was replaced today with a new heifer?”

Eventually, each and every cow gets replaced, Eicker reminded. Even the best, healthiest cows reach a point where it makes more economic sense to get rid of her than keep her.

Culling a cow involves “cash costs” and “economic costs,” Eicker said. Cash costs include the price of a replacement heifer minus the salvage value of the cow being culled.

But he argued that cash costs “do not accurately reflect the economic impact of a cull.”

He offered this example n admittedly, an “extreme” one: A cow is 10 years old and producing a mere 10 pounds of milk. What’s more, her milk has a high somatic cell count n and she’s lame.

None of that matters when it comes to the cash cost. The cash cost of culling old bossie is still $1,100 - $1,500 for her replacement minus bossie’s $400 value as hamburger.

On the other hand, “The economic value of this culling decision is very large and positive,” Eicker said. “If the economic benefit of the cull was not positive, the dairy should not cull the cow.”

Eicker identified two types of premature culling. One is when her culling is not justified in economic terms.

“If the future productive potential of a cow is not correctly identified, she might be culled before her value to the dairy declines below the value of replacing her with a heifer,” he said.

The second kind of premature culling happens when a cow is sent packing before the ideal time. This premature culling could stem from an injury or some other health problem.

“These are usually not errors in culling,” Eicker contended. “Instead they are signals that other management areas need attention so the potential of cows is not damaged and their value (is not) lost prematurely.”

Both kinds of premature culling can be prevented, Eicker said.

“The first can be avoided by more careful and more frequent calculation of the value of a given cow in her slot,” he explained. “Improved cow management and dairy management avoids the second.”

While replacing a cow too early can lose money, so can replacing her too late.

“Retaining a cow in a slot beyond the point where the value of the slot is enhanced by a replacement is a decision to retain a comparatively nonproductive asset,” Eicker asserted. “Keeping a cow because she is ‘paying her way’ is not the same as retaining a cow because she brings more value to a slot than a replacement (does).”

On many farms, cows that are going to be culled stick around longer than they should, he observed. “Perhaps the most costly type of mistake in delaying culling is the error of letting a poor first-lactation animal stay for a second lactation, to ‘see if she does better.’”

While it’s costly to hold onto a poor producer too long, it’s also costly to get rid of a cow before her replacement has calved.

“An empty slot is very expensive,” Eicker warned. “Under generally prevailing conditions on American dairies, the lost profit is $2 to $3 per day.”

Eicker offered several “practical conclusions”:

- Always operate a dairy farm at capacity.

- If you maximize the profit of each cow slot, you maximize the dairy’s profits.

- Diseases cost money.

- “Last year’s culling is a poor method of monitoring herd performance.”

- Longevity can lower replacement costs. But profit is still more important.

- With excellent heifer management, reproductive management and health management, a farm is “likely” to have a cull rate of nearly 40 percent.

- The culling rate depends on the current and projected economic climate.

- Cows that you know are going to be culled should leave when they are producing about 20 pounds of milk below the herd average.

- The profitability of replacing a cow is independent of the desire to add cows. Culling and expansion are different issues.

Comments »

Comment on this story

Comments will be approved within 48 hours

Name:

Email: (optional)

Comments:

Image Verification: (Case sensitive)