There’s something about selling heifer calves that goes against the grain of many dairy producers. Raising every heifer born alive to maturity is the gold standard to which these producers and their employees hold themselves, and to aim any lower is quite simply, heresy.

But, raising every calf and freshening every heifer is not always the most profitable decision for your dairy.

Recent studies at Iowa State University indicate real differences in herd profitability depending on replacement-heifer quality — especially when the cost of replacements is high. That means it’s time to change your way of thinking when it comes to raising heifers. Culling some young calves can help improve your profitability picture.

The numbers tell the story
Data from DHIA records reveal an alarming trend regarding the departure of two-year old heifers before they calve a second time.

Although not usually tracked well on most dairies, researchers say it’s not uncommon for first lactation cull rates to climb as high as 40 percent or more. And, no dairy makes money on an animal it has to cull before recouping her rearing cost. Net returns to your dairy are highest when cull rates for first lactation cows are low. Well-managed dairies can achieve a rate of 10 percent or less.

Management issues or poor initial quality of replacements usually lead to high cull rates during the first lactation. Or sometimes both occur. Therefore, all other management parameters being equal, eliminating some heifers from your herd before they reach maturity — especially if you have a heifer calf surplus — will boost profits.

This strategy allows you to pick and choose the replacements you raise — animals with higher genetic merit and milk production potential than your herd average.

Commit to change
Making this change requires you to commit time and energy to keeping good records, as you will need to monitor several parameters in order to make informed culling decisions. (For more on using heifer records, see the two related stories on pages 26-34 in the January 2003 issue of Dairy Herd Management.) 

Birth weight, disease incidence and genetic merit are three key areas you will need to track. And, animals must receive permanent identification for accuracy. However, the positive financial implications and increased milk production results will more than repay your efforts.

Target birth records
Sometimes it’s easy to spot potential duds.

“Occasionally you’ll have a calf that is a bovine viral diarrhea carrier that is an obvious cull,” says Pat Hoffman, University of Wisconsin extension dairy specialist. “Or one that just isn’t thrifty, she doesn’t look ‘right.’ She may have had a nasty bout with pneumonia, scours or some other disease, and you just know you don’t want her around because she’ll never make up for lost ground.”

But most of the time it’s not that simple to predict future performance, especially if you don’t track calf birth weights or disease incidence. You need records to supplement your visual appraisal.

Iowa State University researchers examined DHIA records for more than 5,100 cows in 121 herds. They found that certain calf information is highly indicative of first lactation milk yield and lifetime performance. For instance, birth weight,  genetic merit and selected health indicators accounted for about 62 percent of the variability for first lactation milk yield among heifers in the same herd.

“We were favorably surprised at how useful and predictive the calf information was on cow performance,” says Marj Faust, Iowa State University extension dairy specialist.

Heifer birth weight is the most consistently important indicator. Data indicates extremely low and high birth weight calves should be targeted for early culling. The optimal birth weight range appears to be between 65 to 90 pounds for Holsteins, with some slight variation based on your herd dynamics.

For example, according to the research, a calf weighing 66 pounds at birth — in the optimal birth range — will produce about 3,300 pounds more milk in her first lactation than a calf weighing 114 pounds at birth. Even with milk priced at $10 per hundredweight, that’s an extra $330 in your pocket.

Good genes matter
Since it is nearly impossible to just look at a calf and determine her genetic potential, it’s essential to know her parentage and sire proof results. Parent genetic averages — adding sire Predicted Transmitting Ability (PTA) to dam PTA and taking the average of the two — for yield traits are good predictors to use to decide which calves to keep.

According to many genetic research studies, heifers from sires with higher PTA milk yield traits — those from the 80th percentile ranking and above — produced more milk in their first lactation than calves from bulls with lower rankings. And daughters of the highest ranked PTA bulls produced the most milk.

Sire PTA for somatic cell count did make a difference in daughter milk yield, but only during the first lactation. However, since this helps evaluate whether she stays in the herd, this parameter has significance. Daughters from the lowest somatic cell count PTA bulls used in the herds examined produced the most milk.

All told, replacement genetic quality has a significant financial implication over and above the cost associated with early culling. The Iowa State researchers reported that a high-quality replacement heifer would be worth $681 more over a normal lifetime than an average-quality animal. In this case, the high-quality animal was assumed to be 10 percent above the herd average for milk production potential and somewhat lower than herd average for post-calving disorders.

Positive passive transfer
Calf immunoglobulin (IgG) levels also proved to be critical for future animal performance in the literature scrutinized in the Iowa State research.

Birth weight impact on first lactation milk production
Birth weight has a long-lasting impact on cow productivity. Calves in the optimum birth weight range (65 to 90 pounds for Holsteins) have significantly higher first lactation milk production than their lighter or heavier counterparts. Iowa State University

The researchers decisively concluded in these studies that calves with inadequate passive immunity transfer carried these production-limiting burdens as heifers and cows. That’s because calves in these studies with poor absorption of IgG had slower growth rates, poorer feed conversion and increased disease incidence. And all of these points resulted in less milk production during the first lactation.

These animals were at greater risk for performance-limiting diseases like pneumonia, scours and premature culling during the first lactation. The researchers did note, however, that some of the diseases had more impact than others, depending on how quickly the calf recovered, disease severity and seasonality effects.

It pays
The bottom line is that accurate heifer information can be used to identify, with a reasonable degree of certainty, which heifers are more likely to be the least productive cows. This allows you to weed out any sub-performers early and reduce the odds that they will be culled during the first lactation — before you get your money back.

Using objective criteria, “it suddenly becomes clear which heifers are at the bottom of the herd and will be the least productive cows,” concludes Faust. “We could see it in the data, but when producers have the calves in front of them, it’s even more apparent.”

It’s time to rethink the idea that you have to raise every single heifer to be a good producer. Instead, choosing to selectively raise a few less heifers could make you a more profitable producer. Remember, though, this profitability advantage holds true only if you have herd turnover rates under control and your heifer program produces plenty of animals to choose from. But if you already have lowered your overall herd turnover, the next logical step is to stop raising every heifer born on the farm.

 

Trading up or cashing out:

Five things you should consider before culling heifers

Culling unworthy heifers as calves does work, says an Eastern Iowa producer who has tried it. He reveals that first lactation production has risen and 2-year-old cows are seldom culled.

However, there are several financial and operational factors to consider before instituting an early heifer culling program, say Bob Matlick, a partner with Moore, Stephens, Wurth, Frazer and Torbet, LLP, certified public accountants and consultants in Visalia, Calif., and Marvin Hoekema, a dairy consultant with Dairy Strategies, Inc., also based in Visalia, Calif.

1. First, evaluate your heifer-rearing program. Determine its strengths and weaknesses, so you know whether you have management issues to improve. Look at housing and facilities, colostrum management, feed inventory and availability and labor. Also determine your heifer raising cost before instituting an aggressive heifer culling program. And factor how your current program fits in with the economics of your entire dairy.

2. One of the most significant questions you need to ask is whether you are just trading cash from one part of your operation to another and from one time period to another. You must know your heifer raising cost to answer this question. And also remember that when you decrease the number of units on your operation, your overhead cost on a per-animal basis will rise.

3. You must also look at the seasonality of your heifer inventory, and factor in death losses. You need to know what your heifer availability is for at least the next six months. Determine whether you want to maintain a steady state or increase your herd size. Seasonality usually accounts for 10 to 15 percent swings in heifer inventory. If you see heifer number increase above that level it’s safer to assume you have a surplus. Then you can be more aggressive with your calf culling program if that’s what you decide to do.

4. Split your heifer raising program into components — wet calves, early weaning, yearlings — so that you can more easily determine animal worth, investment level and marketing opportunities. Run a budgeting program to decide when in the rearing process it is most financially rewarding for you to make culling decisions.

5. Finally, be sure to discuss your strategy with your lender. Make sure he understands your management philosophy and is comfortable with it. After all, these heifers may count as collateral, and inventory changes can alter your financial situation.