Dairy

Three Benchmarks for Breeding Heifers by Size

Management : Calf & Heifer Care

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Over the last 10 years, there has been increased emphasis on growing heifer calves faster and more efficiently to maximize performance and the health of the animal over its lifetime.

The acceptance of this idea has grown among dairy producers. However, one negative outcome of this is approach is that these larger heifers are not being bred early enough to take full advantage of this more aggressive calf growth plan.
 
Bump up heifer breeding timeline
Many heifers are still being bred at the same age as before, even though they could easily be bred two to three months sooner based on size. Heifers bred late are often associated with increased metabolic problems at calving such as ketosis, lower milk production and wasted feed dollars. Breeding based on size of the heifer could help address these types of problems.
 
The following are some size benchmarks to consider with heifers:
  • Measure the average weight on the mature (third plus lactation) animals in your herd. Heifers can be bred when they weigh 55 percent of the mature herd size.
  • Wither height of the heifers should be at least 49 inches tall (Holsteins) to ensure proper frame.
  • Heifers should weigh around 85 percent of mature herd size after they deliver the calf and reach at least 53 to 54 inches tall (Holsteins) at the withers.
These breeding benchmarks can typically be hit by 13 to 15 months of age on most farms, allowing heifers to calve at 22 to 24 months of age when bred by size. Some very well-managed operations may hit these targets even earlier. But, breeding at younger than 13 months of age is something that needs to be given proper thought and management consideration.
 
Selling open heifers 
If you measure your herd and find that you have open heifers past these benchmarks, there could be a silver lining. Beef markets today are still strong and could be a way to generate some extra cash flow by selling open heifers that might be too old or too big for breeding.
 
As long as you would still have enough replacement heifers left on the farm for your herd numbers and you start breeding by size, selling open heifers is a very viable option. For example, a 100-cow dairy with a 35 percent annual cull rate would only need 70 total heifers to maintain herd size if the age at first calving is 24 months. This same herd would only need 64 heifers if the age at first calving is 22 months. In the end you could have some extra cash, properly sized heifers at breeding and calving, better producing first lactation animals and lower heifer rearing costs.*
 
Calving heifers in sooner could help create a healthier bottom line, especially when feed costs continue to climb nationwide. 
 
*Purina Animal Nutrition LLC is dedicated to producing the highest quality animal feeds and supplements.  Due to influences outside of Purina Animal Nutrition LLC’s control, results to be obtained, such as financial performance, animal condition, health or performance cannot be predicted or guaranteed by Purina Animal Nutrition LLC.
 
Three Benchmarks for Breeding Heifers by Size, El Lechero, February 2013