Pork's Quest for Quality
Gene mapping receives significant attention in production research
by Larry Aylward, managing editor
Controlling genetics means making more money, and pork producers continue to seek different avenues to remain on the cutting edge of technology as it relates to genetics.
Gene mapping continues to receive significant attention in genetic research as it relates to the pork industry. Gene mapping is the identification of the location of genes that control the economically important traits in the production of pork.
"The targets cover everything from reproductive ability through growth and efficiency of lean production to pork quality," a genetics expert says. "It also includes other areas such as disease resistance."
Mapping the swine genome will provide researchers with the fundamental genetic knowledge necessary to develop procedures and strategies that will allow genetic improvement to occur at a more rapid rate and in a more predictable manner, says Richard Frahm, director of USDA's National Animal Genome Research Program.
"The more that is known about specific genes, where on the chromosomes they are located, how they are controlled, and how they function, the better chance geneticists and swine breeders have of facilitating favorable genetic change," he stresses.
Rodney Goodwin, director of research programs for the National Pork Producers Council, says the University of Minnesota, University of Wisconsin, Purdue University and Iowa State University have research labs that are doing fine work in the study of gene mapping.
"You can strike gold if you find the right combinations," Goodwin notes.
Advancing biotechnology is giving hope for improvement in specific traits with identification of specific and unique genes, a source points out.
"Traits that continue to be economically important are pigs/sow/year impacted by ovulation rate, uterine size, mothering ability and other factors difficult to quantify," according to the source.
Genetics and further processing
Because a large percentage of pork is further processed, areas such as water holding capacity, protein content and other processing enhancements will be the focus of research, a source claims.
"The current focus on quality has been to reduce backfat," he adds. "The average backfat of the U.S. slaughter market is very high, more than 1.25 inches. With proper genetics, feeding programs and management of finishing pigs, one would expect an average of less than three-fourths inches backfat.
"Thus, packers today could, with the implementation of quality genetics, increase salable product per pig substantially," he adds.
Another expert in the field adds that producers desire highly reproductive sows that produce fast and efficient growing market hogs.
"In the end, the consumer needs to see pork as a healthy, competitive, attractive and nutritious source of protein," he says. "The inheritance or genetic component of many of these attributes are not all fully understood.
"Research is increasingly moving from the production of the live pig end over to the processing end to find differences between the breeds available and the mode of inheritance."
Dennis Harms, president and co-chairman of Premium Standard Farms, claims the Princeton, Mo.-based company is obtaining up to seven more pigs-per-sow-per-year than the industry average. This equates to about 14 or 15 additional pigs.
"We're the only production firm that has capacity to drive 80,000 sows with 750 males," Harms points out. "Under natural mating circumstances, it would take nearly 5,000 boars. This means we're using the best 10 percent to 12 percent of the male population."
The process could increase the plant's lean yield by 1 percent to 2 percent, he adds.
Are any pork packers and processors leaders in the field of genetics? An expert says not one company is dominating the technology, but companies such as Premium Standard Farms and Smithfield, Va.-based Smithfield Foods Inc. are attempting "to exploit a genetic source to provide consistent quality products to their customers."
In a report published by NPPC's Genetic Programs Committee as part of its National Genetic Evaluation Terminal Line Program, Iowa State University's John D. Lawrence points out that several technologies are being commonly practiced in modern pork production. These include selective over-breeding, segregated early weaning, split-sex phase feeding, high-speed single species feed mills and artificial insemination in commercial herds.
Gregg Bevier, Premium Standard Farms' senior vice president of production operations, delivers 35,000 pigs a week-producing the same weight with no variations and the same ham and loin sizes with no variations-to Premium Standard Foods, the company's fresh pork processing operation.
"We practice 100 percent artificial insemination," Bevier says. "Artificial insemination allows you to leverage superior males. The average litter per sow is around 11.2 pigs."
The bottom line is the bottom line. And genetics impact a packer's bottom line. "There are genetic differences in leanness, carcass yield, lean yield and cutout yield that can increase the percentage of higher value salable product and reduce the cost of production of 1 pound of protein," an expert notes.
"If there was a difference of 5 pounds of lean from a single ham between two sources of genetics, then the costs of producing 100,000 pounds of lean ham a day for 235 working days is more than $1 million a year just in boning costs, he adds. This is an extreme example. But it also takes the right nutrition, handling and management through a complete system to realize that potential or difference."
NPPC Unveils Genetic Study Results
The National Pork Producers Council Genetic Programs Committee recently unveiled the results of its National Genetic Evaluation Terminal Line Program in the form of a 312-page book.
A part of the program consisted of a national consumer taste preference study conducted during the last quarter of 1994. Consumers taste-tested broiled, unseasoned samples of boneless pork loin and boneless chicken breast. Pork loin varied by quality attributes and price.
Conclusions of the study revealed:
-- Tenderness was important to consumers, with chicken breast being more
tender.
-- The value of total lipid content of pork loin is high. Industry seedstock selection programs are reducing lipid as backfat is reduced because of the genetic correlation.
-- Ultimate pH of the loin is important and better identification of the RN gene is desirable. A normal (no RN gene) loin with low ultimate pH usually produces tougher meat.
"We've plowed a lot of new ground," says Rodney Goodwin, director of research programs for NPPC.
According to Goodwin, the study was conducted to find whether consumers could tell differences in pork quality traits and whether they could assign higher values to those traits, and what the economic value of pork quality traits might be