Pietrain Breeding in Youth Project Pigs: Pros and Cons
Livestock Update, July 2000
Cindy Wood, Animal and Poultry Sciences, Virginia Tech
Packers and consumers have been pressuring pork producers to raise lean, heavily-muscled pigs for years, and placings in live shows and carcass contests have reflected those goals. Although management and nutrition do influence a pig's body composition, genetics has been the major influence in changing body types seen at shows across the country and in Virginia. At the same time, many youth programs such as 4-H have been re-tooled to educate participants in the economics of raising animals for food by adding a growth efficiency component to live shows and carcass evaluations. As so often happens, these goals do not always converge, which is where the Pietrain question arises.
Pietrain pigs originated in Belgium and became popular throughout Europe during the latter part of the 20th century because their carcasses yield a very high ratio of lean to fat. Figures quoted for the breed include 66.7% usable lean. From a visual standpoint, Pietrains are wide down the back, with extremely bulging muscles in the ham. They also tend to be short legged and stocky, and often they mature at the lower end of the desired weight range. They are white with black spots, and have erect ears. Sows can be prolific, but may lack somewhat in mothering characteristics and in milk production.
Pietrains were imported to the U.S. as a source of heavily muscled animals during the 80's and 90's, and the genetics soon found its way into show pigs. However, along with the increased emphasis on leanness and muscling came an increased incidence in pale, soft, exudative (PSE) pork in the U. S. swine industry. PSE pork is considered unacceptable in quality by packers, processors, and consumers. Many instances of PSE pork can be traced back to a recessive genetic condition called porcine stress syndrome (PSS). In addition to pork quality problems, animals with the PSS gene tend to grow slower than littermates without the gene and may have a more nervous temperament. If a pig happens to get two copies of the PSS gene, it will be highly excitable or nervous and is likely to die if stressed at market weight. Unhappily, Pietrains have one of the highest frequencies of the PSS gene. Although breeders have begun testing for the PSS gene, and you can find some Pietrains which are stress-free, we do not recommend that anyone keep back any breeding gilts with Pietrain breeding. If rate of gain is part of the judging criteria for youth projects, pigs with Pietrain breeding tend not to compete as well, and may not make weight for a show.
For information on the Pietrain breed, and other breeds of livestock as well, the Oklahoma State breeds site (http://www.ansi.okstate.edu/BREEDS/) is an excellent starting point.