Farm & Ranch Guide – From neonatal nutrition to genomic testing, the way we raise heifers has been revolutionized over the last decade with the promise of more productive and profitable offspring knocking at the parlor door with each generation of herd replacements. Technology, however, comes with a price tag. Are the investments in advanced feeding and genetic programs paying for themselves?
As part of the 2013 Repro Money Roadshow, Pat Hoffman, UW-Extension dairy specialist, is challenging producers to think about how they are capitalizing on practices like intensified feeding and genomic testing in a way that generates profit.
The evolution of calf-feeding in recent years has raised the bar for growth. With advancements in nutrition, it is attainable to double a calf’s birth weight in her first eight weeks of life. From higher protein milk replacers to whole milk pasteurizers and automated feeders, the difference technology is making in calf growth is the equivalent of about 40 extra pounds per calf at weaning. This translates into 20 days worth of growth, and that increment is enough to shift the age at first breeding up by roughly one month.
Hoffman points out that the carryover effect of doubling birth weight in those first eight weeks translates to about 1,200 pounds more milk in the first lactation.
No doubt, feeding more is going to cost more. That leaves us wondering is every calf worth the extra expense? The answer to that question may lie in genomics.
“To improve female genetics, it really requires capitalizing the cost out,” he explains. That means taking some sort of action based on the results of genomic testing, such as breeding high-numbers heifers to sexed semen or low-numbers heifers to young sires. To take that one step further, culling the bottom 15 to 25 percent of heifers can have a profound effect on genetic improvement in the herd by bringing up the averages.
Utilizing the science of genomics allows producers to maximize the potential for their animals based on genetic influence, but management is the other piece of the puzzle. Hoffman points out that the heifer management strategies of the past may not be efficient enough to keep up with the speed at which decisions must be made to truly capture the benefits of technology.
“At the UW herd, we found we need more stringent breeding criteria because of the timing and quick turn-around of these kinds of tests that influence breeding decisions,” he says.
On many dairies, factors like weight and height drive the decision to breed a heifer or wait it out until her next cycle. These “eyeball metrics” are based on observation and whether or not the heifer looks big enough to breed. Each time you make the decision to wait, it costs you money, Hoffman points out. Estimating feeding costs at $2 a day over 21 days, that decision costs roughly $50.
Delaying first breeding can result in a wide distribution of age at first calving, or a “stringing” effect. “What can happen if you are not careful is your true pregnancy rate on heifers can get strung out,” he says. He suggests age as a better deciding factor for breeding heifers. “The one method you can really bank on is age. You know what it is and it’s easily attainable,” he says. “That’s one thing you can specifically quantify.”
Hoffman also recommends that producers shift their mindset from looking at averages to variances when it comes to age at first calving. One way to do this is to pull data from the farm record keeping system to create a graph of calving age distribution.
“If you see a calving age distribution that is normal – about the same number on the left as there is on the right and no peak in the middle – that would indicate massive stringing in the herd,” he says. What is more desirable is steep right-tail distribution. When graphed, the tallest bars would be close to each other, for example, at 22, 23 and 24 months of age. The bars to the right going onto 29 months would be decreasing at a steep angle. This shows less variation in age of calving, which is the result of making confident decisions on when to breed heifers. When heifers are not calving in until 28 or 29 months, that could represent an additional 600 pounds of body weight on first-calf heifers. Putting on that weight is costly, and over-conditioned heifers will be more likely to have difficulties with freshening and transitioning.
Tightening up the age of first calving can also be beneficial when we consider calving heifers in at 23 months of age can give them a first-lactation milk production advantage. But, much like realizing the benefits of feeding and genomic testing, management practices truly determine whether or not it pays off in the long run.
In a study of the carryover effects of age at first calving on lifetime milk production, heifers calving in at 23 months were compared to their herdmates that calved in at 24 months. While one might assume the additional month of milking would directly relate to more lifetime milk, such is not always the case. According to Hoffman, herds milking two times a day had no significant gain among the group of earlier calvers. Those that calved 30 days younger simply left the herd 30 days earlier. However, herds milking three times a day captured the equivalent of 16 more days in milk. He hypothesizes that this observation could be in part due to the constraints of stall barns were 2X milking is more commonly done, and culling decisions in these barns may be based more on available space.
Again, he points out, the heifer management philosophies of the past may not be efficient enough for investments in advanced feeding or genetics pay for themselves.
“We cannot see where the old paradigms of heifer management really fit very well,” he says. “We cannot afford to wait because by 13 months of age we have to anticipate what is going to happen everything gets compressed down into that first year of life to try to capitalize on [technology].”
