A Survey of Relationships Among Rare Breeds of Pigs

View the project final report

• 2012 annual report

Commodities

• Animals: swine

Practices

• Animal Production: animal protection and health, livestock breeding
• Education and Training: extension
• Natural Resources/Environment: biodiversity

Vertical integration of agriculture has dangerously reduced genetic variation among breeds used in commercial operations. Though benefits of biodiversity are often overlooked, there are farmers and organizations interested in preserving rare and endangered breeds for future generations. A constraint faced by many is the lack of pedigree data available for these breeds, which makes planning matings to avoid inbreeding difficult. Inbreeding increases homozygosity, therefore reducing genetic variation. Inbreeding often leads to the appearance of undesirable or deadly homozygous recessive traits which reduce a breed’s viability. This project focuses on increasing interest in rare pig breeds by expanding the genetic knowledge available to producers and the public. The main outcomes of this project are: 1) Establish relationships among animals without pedigree data; 2) Increase producer awareness of genetic variation in order to preserve rare breeds for future generations. Three viable, rare pig breeds with little or no pedigree data will be selected for evaluations. After collecting and genotyping DNA samples, relationships will be established for animals within these breeds of swine. Accurate relationship data will allow producers plan matings to maintain genetic diversity. Greater genetic variation will allow rare breeds to remain viable for future generations, providing farmers opportunities for niche marketing. A follow up with producers involved in this project will evaluate how the relationship data and genetic information has aided their reproductive management.

Introduction:

Genetic diversity allows adaptation to environmental changes and varied disease resistance. Without such diversity, a population could be decimated by disease or environmental fluctuations. Swine breeds facing extinction share characteristics such as small size, slow growth rate, and high fat percentage, which eliminate them from the high-input high-output business of commercial production. Small populations and lack of genetic information increases the chance that producers are breeding closely related individuals, which ultimately eliminates genetic diversity by increasing levels of homozygosity in subsequent generations. By making genetic data available, producers can make more educated breeding decisions to preserve genetic diversity in future generations.

Objectives for this project include calculating genetic relationships among rare breeds of swine, comparing rare and commercial breeds of swine, and providing producers with the information so they can make more informed breeding decisions.

Originally, only three rare breeds were going to be analyzed, but I was able to obtain samples from six rare breeds and an additional four commercial breeds.