Last January, USDA issued new interim final rules to protect the public from the prions believed to cause BSE. The regulations covering specified risk materials (SRMs) and the use of advanced meat recovery systems meant all segments of the industry had to create and implement plans to certify the age of cattle as either under or over 30 months.

Today, Cap Proffitt, manager of Barton County Feeders, Inc., Ellinwood, KS, knocks on wood when he talks about the new rules.

“Initially, there was panic and chaos when they came out with the 30-month rule,” he says. “We ran across a significant percentage of cattle we knew through producer records were under 30 months old. But the mouth checks indicated they were over 30 months.”

Proffitt immediately sent the alarm out to his customers that they needed to be very careful when speculating on “opportunity cattle.” Without age documentation, the risk of price discounts was very high.

The USDA regulations classified the skull, brain, trigeminal ganglia, eyes, vertebral column, spinal cord and dorsal root ganglia of cattle over 30 months of age, as well as the small intestine of all cattle regardless of age, as SRMs and prohibited their use in human food. Age distribution research data show that of the cattle that have developed clinical BSE in the field, only 0.01% were less than 30 months of age.

Exports aside, it was believed early on that discounts for cattle more than 30 months old could result in a 30-50% loss in domestic value compared to a carcass from a similar animal less than 30 months of age.

Not an exact science

USDA's Food Safety Inspection Service (FSIS) instructed veterinary officers in packing plants to “age” cattle using the dentition parameters. But as Proffitt found, it's not an exact science.

Dee Griffin and David Smith, University of Nebraska Extension veterinarians, recently outlined the regulations prescribing two approved methods for determining the age of an individual animal:

  • Documentation that identifies the age of the animal, such as a birth certificate, cattle passport or some other form of ID presented with the animal when it arrives for slaughter.

  • Examination of the dentition of the animal to determine whether at least one of the second set of permanent incisors has erupted (the permanent incisors of cattle erupt from 24-30 months of age).

“Dentition can be used in the absence of documentation. Unfortunately, it only provides a general determination of age,” Griffin says. In fact, the use of dentition for age determination in cattle has been questioned for decades.

The eruption of permanent incisor teeth can vary depending on factors such as breed, diet and season of birth, says John Basarab, researcher and beef management specialist with Alberta Agriculture, Food and Rural Development.

He and other Alberta scientists recently reviewed research on the relationship between cattle age and dental eruption. They found it's likely that 16-50% of the youthful cattle harvested and categorized by dentition as being over 30 months of age are actually less than 30 months.

“Because these studies are more than 20 years old, there's a need to characterize the current cattle population for the relationship between age and the eruption of permanent incisors,” Basarab says. “Changes in genetics, management and feeding programs have likely changed the mean age of emergence of the lower permanent incisor teeth in cattle.”

Acceptable documentation

USDA feels documentation is the best way to determine the age of cattle because it's more specific. The agency publicly recognizes that the permanent incisors of cattle erupt from 24-30 months of age, but USDA has determined the described dentition procedure will be most protective of public health.

FSIS has characterized acceptable documentation as records or certificates related to individual cattle rather than information about an entire lot. It should provide evidence of age that goes back to the farm where the cattle were born, including the name and the address of the owner. These documents include:

  • Pregnancy-check records and results for individual cows.

  • Records of which cows were in a herd when a bull was put in with the herd.

  • Records of when the bull was removed from the herd (to determine start of gestation).

  • Documentation showing when individual cows were artificially inseminated.

  • Calving records that document where and when a calf was born.

  • ID applied to calves — branding records, electronic IDs or ear tags.

Avoiding discounts

In order to minimize “heiferette” discounts that might be passed back to the rancher, Ted McCollum suggests ranchers use herd management strategies to reduce the required number of replacements and optimize conception rates. The Texas A&M University Extension beef cattle specialist also says to determine pregnancy and cull as early as possible.

He says the 30-month age regulation may also influence when stocker cattle producers and cattle feeders purchase cattle.

Proffitt says many packers originally indicated they would come to the feedlot and segregate cattle that visually appeared to be reaching 30 months of age. Another packer said they'd sort off cattle that “looked suspicious” at the plant. If they were determined by dental inspection to be more than 30 months, they'd be purchased using a grid.

“That didn't last too long — 90 days maximum — and no one is doing it anymore,” Proffitt says. “I hear nothing about ‘30-plus’ cattle anymore.”

He emphasizes though, that his customers intentionally quit buying cattle that would fit into that age group.

“Our customers started steering away from those cattle — at least on a pen basis,” he explains. “I wonder, though, if there are some 30-plus cattle getting through the system somewhere along the line.”

In visiting with packers, Proffitt says the most significant revenue loss — about $8/animal — is occurring because the heads of cattle 30 months and older aren't being processed.

“But it doesn't appear at this point the packers are passing that loss back down the line,” he says. “So far, we're just not seeing a problem with discounts related to 30+ cattle. But, we're also aware that this could all change at any time.”

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