In an effort to increase their return on investment, many producers are analyzing their production system and fine-tuning their management to allow for a maximization of efficiencies.
A key driver of profitability in a beef operation is the reproductive efficiency of the cow herd.
On average, a cow is pregnant 285 days of a 365-day year. Cows that calve on a yearly basis provide greater profit to a producer because they are producing marketable calves on a consistent basis.
A 12-month calving interval is vital to achieving this consistency. To maintain a 12-month calving interval, the calving and breeding seasons can be no longer than 80 days. This means the 80-day breeding period is the only opportunity for the cow to become pregnant.
An 80-day breeding/calving season can increase efficiencies for many U.S. beef producers and have a positive impact on their profitability. The 2007 USDA-APHIS and Veterinary Services NAHMS survey found that 46.1 percent of U.S. beef producers have calves born throughout the year rather than a specific calving season.
Many studies show a considerable economic benefit to maintaining a calving season of 45 to 80 days. Some of the benefits to a short calving season include:
- A more uniform calf crop at weaning: Producers that maintain a tight calving season are better prepared to meet the demands of the current beef market for more uniform groups of calves. Long calving seasons result in a wide range of ages and weights in calves at weaning time, reducing calf weaning weights and decreasing consistency.
- Concentration of labor: When the calving season is kept within a shortened time frame, producers can focus on cow husbandry, newborn calf management and labor during the calving season and proper calf care once calves are on the ground.
- Strategic herd management: Breeding the herd during an 80-day period allows all cows to be in the same stage of production throughout the year. Cows can then be fed, vaccinated, bred, pregnancy checked and managed on a consistent timeline.
Strategies for implementation
There are many strategies that can be used by producers to achieve the goal of an 80-day calving season. Which strategy a producer uses to implement a tighter calving season is dependent on their herd size and current calving season length.
In a year-round calving season situation, it will take a few years to achieve an optimum calving season with cows currently not breeding within the 80-day period being transitioned to the schedule over time.
Seasonal breeding herds can shorten their calving seasons by focusing on reproductive strategies after each cow calves.
In many operations, the easiest area to make an impact is in the management of replacement heifers. In this case, the producer would identify the dates for calving and plan key management times appropriately.
Many operations breed heifers three to four weeks prior to the mature cow herd, allowing the heifers extra time to recover from calving before the breeding season begins.
By allowing first-calf heifers extra recovery time, they have less potential to delay future calving seasons. Calving dates can be regulated by managing bull exposure/removal, artificial insemination programs and other management systems.
Estrus synchronization protocols
Synchronization of estrus (heat) can also be used to achieve a tighter calving season – with the potential to maximize the number of animals bred (and potential pregnancies) in a short period of time.
Traditional estrus synchronization protocols are designed to control the follicular waves that occur on the ovary during the estrous cycle to maximize the number of animals expressing estrus within a short period of time.
New protocols have been designed to control the timing of ovulation, allowing for timed artificial insemination (TAI) to occur on a set day and time.
There are many protocols available for synchronizing estrus in cattle in either of these categories. When instituting a synchronization program, consult with your veterinarian, local extension agent or other industry representatives to determine the best protocol for you and your operation.
Pregnancy checking
Once females are bred, they need to be pregnancy checked to ensure pregnancy status. If a female is confirmed to be open, she can be monitored for estrus and re-bred (if still within the set breeding season) quickly to avoid a staggered calving season and increased input costs required by open females.
If the pregnancy check occurs after the end of the breeding season, the female can be removed from the herd and marketed accordingly.
Producers that do not routinely check for pregnancy often have higher input costs associated with their marketable calves simply because they are feeding open cows that will not generate revenue.
According to the USDA-NAHMS 2007 U.S. Animal Health Report, only 18 percent of U.S. beef operations check their cows for pregnancy.
The most common reason cited by producers was the requirement of labor and time (34 percent). The cost of labor and time for pregnancy testing can be easily recovered by the decrease in input costs and is a critical part of a successful reproductive management program in a cow-calf operation.
Today, there are three methods available to producers to determine the pregnancy status of cows: rectal palpation, ultrasonography and chemical pregnancy tests.
Rectal palpation, performed by a veterinarian or technician, is the traditional method for determination of pregnancy status.
The uterus is examined for the following signs of pregnancy: fetal membranes as early as 30 days post-conception, placentomes (cotyledons and caruncles) by day 75 to 80 of pregnancy and actual fetus around day 65.
Over the last decade, ultrasonography has become more popular. Ultrasonography – or ultra-sounding – is the use of a rectal probe to examine the uterus for the presence of the signs of pregnancy mentioned above.
Ultrasounds can be used for examinations earlier than rectal palpation but still cannot be used prior to 26 to 28 days post-breeding.
In recent years, new technologies have been developed to evaluate blood samples for pregnancy status. These tests analyze a sample of blood for the presence of proteins produced by the placenta of the growing fetus.
The first of these tests determines the presence of pregnancy-specific protein (PSPB) in the blood. Cows can be determined pregnant or open based on the presence of PSPB in a blood sample.
To blood test a cow or heifer for pregnancy, a producer sends a sample of blood from the cow to a laboratory near them as early as 28 days post-breeding, and in lactating cows, 73 days post-calving.
Tests are near 100 percent accurate when a cow is determined to be open. Once the cow is determined to be open, she can then be re-bred or marketed accordingly to maintain the proper calving window. 176674.png
For additional information on achieving an 80-day calving window through reproductive management and blood pregnancy testing, contact Jeremy Howard at (208) 882-9736 or visit BioTracking.
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New technologies have been developed to evaluate blood samples for pregnancy status. These tests analyze a sample of blood for the presence of proteins produced by the placenta of the growing fetus.
Jeremy Howard
Reproduction Specialist
BioTracking, LLC
