VAP-Pigs

Cards (88)

  • The pig industry in South Africa dates back to 1652 with 24 pigs on inventory
  • The current South African breeding herd is approximately 105,000 sows owned by 400 farmers
  • 2 million pigs are slaughtered per year in South Africa
  • There are 46 pig abattoirs in South Africa
  • There are 36 stud breeders/breeding companies affiliated to the Pig Breeders Society of South Africa (PBS)
  • Pig Breeders Society of South Africa (PBS)

    Established in 1919, affiliated to the SA Stud Book and Livestock Improvement Association
  • Objectives of the PBS
    • Improve general standard of all recognised breeds
    • Keep registry of performance records of pedigrees/purebred boars and sows
    • Enhance functional production/economic merit of stud animals through the National Pig Performance and Progeny Testing Scheme (NPPTS) of the ARC
  • National Pig Performance and Progeny Testing Scheme (NPPTS)
    Facilitates the genetic improvement of the national herd through increased litter size, increased pigs raised per litter, improved carcass quality, and improved growth rate and feed efficiency
  • NPPTS testing modalities
    1. Central testing at Irene, Cedara or Elsenburg
    2. Appraisal of 3 economic traits: % lean meat, feed conversion ratio, and average daily gain (ADG)
    3. Testing starts at 27 kg and ends at 86 kg, with pigs fed a standardised pelleted ration and weighed weekly, plus 2 backfat measurements taken at 77 and 86 kg
  • Rand Value Index (RVI)

    Determined by PIGBLUP and checked by a Panel, with a minimum of >1 for Boars and >0.5 for Gilts
  • On-farm testing
    1. Measures individual performance and is used for selection and genetic improvement by identifying superior individuals, strains, lines or breeds
    2. Testing starts at 23 - 32 kg live mass until reaching 86 - 99 kg, with data used to determine a Selection Index by the Integris system using PIGBLUP
  • Since the 1990s, there has been an intensification of pig production in South Africa facilitated by the development and application of improved genetics and information and management tools, namely Integrated Registration and Genetics Information System (INTEGRIS) and PIGBLUP
  • Characteristics of pig production in South Africa
    • Large intensive production units (75% of units have 200-1000 sows)
    • High capital investment
  • Factors affecting the profitability of pig production

    • Production costs (capital, working, labour, veterinary)
    • Reproduction (breeding output)
    • Production (growth efficiency, feed conversion)
    • Product (carcass mass and grade, % lean)
  • Dead Weight - Feed Conversion (DWFC) or Feed:Pork Ratio
    A cost calculated in relation to the total output of the piggery, representing an index of efficiency of the operation, with a target of around 4.2
  • Factors influencing DWFC
    • Genetic makeup of herd
    • Feeding system
    • Reproduction efficiency
    • Health management
    • Nutrient suitability
    • Organization
  • Registered pig breeds in South Africa
    • Large White (>58,000 animals)
    • SA Landrace (>18,000 animals)
    • Duroc (>10,000 animals)
    • QM Hamline (>1,500 animals)
    • Hampshire (>1,500 animals)
    • Chester White (>800 animals)
    • Pietrain (>15 animals)
  • Large White

    • Large framed, late maturing type, poor ham development, used in crossbreeding (commonly with Landrace)
  • SA Landrace
    • Large litter size, heavy milk producer, excellent maternal instinct, white haired and pink skinned, long bodied, ears looped forward, light forequarters, large hams
  • Duroc
    • Docility and ease of handling, superior mothering ability, reputed muscle quality (marbling), general absence of stress, economical feed efficiency and growth rate, remain lean at high slaughter weights, very easy to handle
  • Breed
    A group of animals sharing a common ancestry that have distinguishable, fixed characteristics who when mated with a member of the same breed will produce offspring with the same characteristics
  • Breeding
    Pairing individuals for breeding in order to incorporate or maintain desired traits
  • Mating strategies
    • Positive assortive mating (like to like breeding)
    • Negative assortive mating (unlike to unlike breeding)
  • Basic breeding systems
    • Inbreeding
    • Linebreeding
    • Outcrossing
    • Random mating within a breed
    • Crossbreeding
  • Inbreeding and Linebreeding
    • Reduces the variety of the gene pool, increases the potential expression of undesirable genes, leads to a decline in performance (inbreeding depression)
  • Outcrossing and Random mating within a breed

    • Used to maintain gene diversity within a breed of pigs, can also lead to inbreeding depression at some point
  • Crossbreeding
    • The most common type of mating system used in the pig industry because of the advantages of heterosis
  • Heterosis
    The improved performance of offspring compared to the average of their parents
  • Heterosis tends to be largest for traits of low heritability
  • Crossbreeding provides significant improvement for traits relating to reproductive performance and mothering ability
  • Crossbreeding systems
    • Rotational
    • Terminal
    • Rotaterminal
  • Rotational crossbreeding
    • Different breeds of boars are rotated, replacement gilts are kept, requires good management of records
  • Terminal crossbreeding
    • Most common system, crossbreed females bred to terminal sire, all the offspring is sold, creates genetically uniform groups but requires purchasing replacement gilts and boars
  • Rotaterminal crossbreeding

    • Combination of rotational and terminal, herd divided into two subsets
  • The breeding pyramid depicts the relation between the purebred stock, multiplier herds and commercial herds
  • Crossbreeding leads to heterosis which increases traits of low heritability
  • Heritability (h2) refers to certain selection traits superiority above contemporaries that is passed to offspring
  • Heritability estimates
    • Carcass traits (high h2 - 40-50%)
    • Performance traits (moderate h2 - 20-30%)
    • Reproductive traits (low h2 - 10-15%)
  • Genetic gain is obtained by taking advantage of heritable traits, high intensity selection and short inter-generational intervals (approx. 2 years in pigs)
  • Congenital defects
    Genetic defects or environmental factors (disease, drugs, diet or chemicals that the sow was exposed to during pregnancy)