Sexed semen economical option for cattle industry
December 19, 2011
The use of sexed semen in the beef cattle industry may only be in the infancy stages, but it’s growing in popularity as ranchers weigh the economic benefits of using it. Sexed semen could play an important role in how ranchers produce cattle in the future.
Les Vogler of Vogler Semen Centre in Ashland, NE, says cattle producers of all breeds and niches from registered, commercial, to club calf breeders, are experimenting with sexed semen.
“It is more expensive to collect semen and sort it for sex of calf, but producers can use the Sexing Technologies Web site to access a calculator with formulas to help them determine if it would be economical for their operation,” he explains.
There are many benefits to using sexed semen. Obviously, it allows producers to produce cattle of a specific gender to meet current needs and markets. However, it can also give producers the ability to raise more heifers from high-quality cows, resulting in superior replacement females and donors. In addition, higher-quality bulls can be produced for cleanup.
Producers can also breed their first-calf heifers not only to light birthweight bulls, but so they produce heifer calves. The lighter birthweight heifer calves reduce calving difficulties and the labor costs associated with it, in addition to potential death loss, Vogler says. Also, since less stress is placed on heifers, they should breed back sooner.
Commercial producers may use sexed semen when there is a gender value difference in marketing, such as the premium for steer over heifer calves, Vogler explains. “The benefits from crossbreeding to capture increases in weaning weights and calves in greater market demand are well documented.
“Using sexed semen in terminal cross production will increase the percentage of higher-valued steer calves,” he adds. An increased spread in feeder price between steers versus heifers could make the use of sexed semen very economical.
Chris Beutler from Bancroft, NE, summarized, “Sexed semen has changed the way we do business, and also the way we select herd sires. Now we focus on maternal bulls with calving ease. This allows us to breed heifers, not only for calving ease, but for replacements. Furthermore, it has helped ‘kickstart’ the promotion of many of our [artificial insemination, AI] bulls, allowing us to gain customers all across the U.S. Also, through the use of embryo transplant, we decide what we want for offspring, whether it is females, or terminal show stock.”
Since sorting their first batch of semen in December 2010, the Voglers have collected and sorted semen from bulls in Nebraska, Kansas, Missouri, Iowa and Minnesota. Being centrally located has been a big plus for the company. Bulls must be brought to the facility for collection, Vogler says. Semen cannot be shipped to the Voglers to be sorted.
“The bull is collected here, then the semen is evaluated and an extender and buffer is added before it is delivered to the Fullerton facility. Temperature control during that period is very important,” he adds.
Once the ejaculate arrives at the Fullerton facility, it takes several hours for the machine to sort the semen. The machine can only sort one bull at a time. “Sexing Technologies strives to put out a high-quality product with rigid QC standards,” Vogler explains. “Pre-sexed specimens must be 6-7 mL with a concentration of no less than 1.1 billion sperm per mL, and motility over 70 percent. A random straw of every batch is analyzed post-freeze at zero and three hours. Motility greater than 45 percent and 30 percent, respectively, are required and a minimum of 87 percent of the desired gender is necessary to approve the release of the batch. Studies have shown that producers may see a 10-15 percent reduction in pregnancy rates in sexed semen as compared to conventional semen.” Vogler says this is due to the concentration of the semen. “When the semen is sorted for X and Y, the dead and abnormal sperm are also sorted out. In the end, the concentration is lower, but it is purer.”
Producers can expect sexed semen to be at least 87 percent accurate. “It can be sorted more accurately,” Vogler explains, “but 87 percent was determined to be the most cost-effective break-off point. Bull owners should be able to expect, on the average beef ejaculate, 120 units of female 2.1 million dose straws and 75 units of male 2.1 million dose straws. The semen is packaged in ¼ cc straws as opposed to the 1/2 cc straws used for conventional AI. This should not require different equipment if technicians are using 1/2 cc or a universal AI gun,” he explains.
The Voglers have collected semen with favorable results. Dave Zeis of Zeis Simmental in Valley, NE reports: “We had excellent results with the female sexed semen collected at the Voglers. Ultrasound results on 76 head of heifers showed nearly 75 percent conception for the sexed semen, which was equal to or better than the conventional semen on this same group. I will definitely use more in the future. The marketability of the heifers bred to female sexed semen should be outstanding, and calving ease will be improved with 90 percent heifer calves born.”
Vogler cautions that not all bulls can be collected for sexed semen. “Each individual is different,” he says. The time of year can influence whether or not a bull can be successfully collected. “Weather has a huge impact, as well as nutrition and the amount of stress the bull is under. We have had bulls that at times have produced a high-quality sort, and at other times won’t.”
Dr. Dustin Dean of Sexing Technologies further explains: “A bull that freezes conventional semen may not always successfully produce sexed semen. While every bull’s cells do either have an X-bearing or Y-bearing chromosome, this does not mean those cells will survive the sorting process. Most of the time, if a bull freezes conventional, he will produce sexed semen. Still, you never know until the bull’s ejaculates have been sorted. The sorting process can be stressful, and some bull’s semen is more vigorous than others. About 20 percent of the beef industry’s bulls cannot be sorted, mainly because of variations in semen quality between bulls. However, the more sexed semen is used in the beef industry, the more we will see bulls with high semen quality. A bull’s semen quality can vary throughout the year and throughout the month. The bulls that usually do the best are the ones just coming off cows or ones that are not in a heavy condition,” he says.
Once the semen is sorted for sex of calf, both the heifer and bull semen sort can be used. The semen can also be frozen indefinitely like conventional semen, as long as it is not thawed and refrozen.
In addition to sexed semen, the Voglers also offer other services at their company. They can custom collect bulls and stallions, they offer mare breeding services, and ship equine semen either cooled or frozen. Sexing Technologies can also sort stallion semen for sex, but the Voglers don’t currently offer that service. They can also store semen for customers, and ship it anywhere in the U.S. and internationally.
Editor’s note: For more information about sexed semen, see the Vogler’s Web site: voglersemen.com, or Sexing Technologies at sexingtechnologies.com.