Swine Breeds & Breeding Detailed Notes

Swine Breed Characteristics

  • Historically, breeds identified by visual characteristics:
    • Hair Color: White, black, spotted, red
    • Ears: Erect or drooping

Swine Breeds Data Overview (Table 28.2)

  • Number of Litters Recorded for Top Five U.S. Breeds of Swine
    • Berkshire: Established in 1875
    • 2012: 38,696
    • 2008: 6,819
    • Duroc: Established in 1883
    • 2012: 73,396
    • 2008: 76,955*
    • Hampshire: Established in 1893
    • 2012: 29,075
    • 2008: 41,311
    • Landrace: Established in 1950
    • 2012: 59,838
    • 2008: 30,804*
    • Yorkshire: Established in 1935
    • 2012: 144,897*
    • 2008: 116,280*
  • The importance of breeds reflected in purebred registration numbers, indicating demand for crossbred operations.

Top Eight Major Swine Breeds

  • Eight major breeds commonly raised in the U.S.
  • Different breeds excel in specific applications based on their qualities and physical characteristics.

Breed Summaries

Chester Whites
  • Origin: Chester County, Pennsylvania
  • Characteristics: White hogs with droopy ears known for:
    • Mothering ability
    • Durability and soundness
    • Muscle quality appreciated by packers
Poland China
  • Origin: Ohio, early 1800s
  • Known for:
    • Large frame and body length
    • Leanness and muscle
    • Excellent feeding capabilities and quiet disposition
Spotted
  • Characterization: Black-and-white spots
  • Known for:
    • Feed efficiency
    • Rate of gain and carcass quality
    • Productivity, docility, and durability appreciated by commercial producers
Landrace
  • White hogs with droopy ears
  • Known as “America’s Sowherd”:
    • Heavy milkers with large litters
    • Ideal for crossing with other breeds
Hampshire
  • Recognized by "the belt"
  • Known for:
    • Lean muscle and high carcass quality
    • Low backfat and large loin eyes
    • Good mothering ability and longevity in the sow herd
Berkshire
  • Third-most recorded breed
  • Characteristics:
    • Fast and efficient growth
    • High reproductive efficiency
    • Cleanly and flavorful meat
Duroc
  • Second-most recorded breed
  • Traits include:
    • Product quality, carcass yield
    • Fast growth and lean-gain efficiency
    • Notable prolificacy and longevity in females
Yorkshire
  • Most-recorded breed in North America
  • Attributes:
    • High proportion of lean meat
    • Low backfat and high durability

Life Cycle of Swine

  • Birth: Health checks immediately after birth
  • Suckling: Feeding on sow's milk
  • Weaning: Separation from the sow, typically at 8-9 weeks or about 20kg liveweight
  • Growing: 9-16 weeks of age or 20-50 kg liveweight
  • Finishing: 16-25 weeks or over 50 kg liveweight; some may be kept for breeding
  • Slaughter: Finished pigs slaughtered any age; categorization into porkers and baconers based on weight

Traits & Measurements

  • Development of procedures for comparing traits across breeds:
    • Use of technology and statistical formulas for predicting genetic merit (Expected Progeny Differences - EPDs)

Performance Information

  • Categories include:
    • Reproduction
    • Growth
    • Composition
  • Presentation of performance records: individual measurements, ratios/indexes, genetic merit estimates (EPDs).

Effective Use of Performance Records

  • Common EPDs:
    • Number Born Alive: expressed in number of pigs
    • 21-Day Litter Weight: expressed in pounds
    • Days to 230: measured in days
    • 10th Rib Backfat Depth: measured in inches

Sow Productivity Metrics

  • Sow Productivity Index (SPI): combines number of pigs born alive and 21-day litter weight adjusted for sow parity.
  • Number Born Alive (NBA): EPD indicates expected litter size relative to group average.
  • Litter Weight: EPD predicts the weight of litters at weaning.

Growth Rate Metrics

  • Terminal Sire Index (TSI): measures growth, feed efficiency, and backfat, calculated via EPDs.
  • Days to 230 Pounds: predicts the time for offspring to reach 230 pounds.
  • Backfat EPD: indicates expected lean meat proportion in progeny.

Selection of Replacement Gilts

  • Replacement gilts raised for good quality offspring; must possess desirable reproductive traits.
  • Maternal Line Index (MLI) emphasizes reproductive over growth traits in selection.

Boar Selection

  • Importance of selecting sound boars for genetic improvement; they influence progeny performance significantly (80-90%).
  • Selection based on growth rate, carcass quality, and physical soundness.

Crossbreeding for Commercial Swine Producers

  • Crossbreeding leverages heterosis, improving traits with low heritability.
  • Benefits seen in litter size, weaning weight, and pig survival rate, while high heritability traits see less benefit.

Commercial Seedstock Production

  • Dominated by specialized companies focusing on genetic improvement through nucleus herds.
  • Nucleus herds maintain purelines and produce highly selected boars for breeding and commercial purposes, creating genetic lines that meet industry needs.