Swine Selection and Life Cycle

1
Swine Selection and Life Cycle

• Chapter 29

2
Swine Traits

• Sow Productivity
• Low heritability
• Can be improved by managing environment
• Measured by
• Litter weight at 21-d measures milk production
• Adequate crossbreeding programs should use breeds
  that have good mothering ability

3
Swine Traits

• Sow Productivity

4
Symbol III
5
(No Transcript)
6
Swine Traits

• Growth Rate
• Economically important
• Reasonable heritability (35)
• Measured by days required for swine to reach
  lb.

7
Swine Traits

• Feed Efficiency
• Measures the pounds of feed required per pound of
  gain
• Heritability of 0.30
• Important of total production costs
  is for feed
• Fast gaining pigs tend to be more feed efficient

8
Swine Traits

• Carcass Traits
• Used to estimate the pounds or percentage of
  acceptable-quality lean pork
• Percent lean heritability is 0.48
• Traits used to predict carcass composition
• Backfat at the 10th rib
• Loineye area
• Carcass muscling score
• Determined by using ultrasound, which you can
  learn how to use in Applied Animal Technology

9
Swine Traits

• Structural Soundness
• The capacity of breeding and terminal animals to
  withstand the rigors of confinement rearing and
  bearing
• Extremely important
• Improved through visual inspection
• Inherited structural unsoundness conditions
• Cryptorchidism
• PSE

10
Performance Records

• Performance is influenced by genetics and
  environment
• Sound genetic improvement program
• Accurate and complete performance records
• Assessment of genetic merit
• Weighing traits with economic importance
• Selection of high-ranking gilts and boars

11
Performance Records

• Genetic evaluation programs
• STAGES computer program that generates genetic
  evaluation for traits in a single herd
• EPDS
• Sow productivity index (SPI)
• Terminal sire index (TSI)
• Maternal line index (MLI)

12
Performance Records
13
Performance Records
14
Performance Records

• NPPC NGEP (National Genetic Evaluation Program)
• Consumer preference studies
• Pork vs. Chicken breast
• Price most important attribute when comparing
• Higher lipid level, greater the tenderness
• Increased lipid level have more than twice the
  economic value than increased tenderness or
  higher pH

15
Selecting Replacement Females

• SOW PRODUCTIVITY!!!
• She contributes half the genetic composition
• Fast growing, sound, moderately lean replacement
  gilts
• Good body capacity
• From a litter with excellent pigs
  weaned
• What sows should be culled?

16
Selecting Replacement Females

• Need to have a balance between replacements and
  culled sows
• Replacing too many sows may decrease the number
  of pigs the operation is weaning
• Typically replace for each
  farrowing
• Replace for and balance between

17
Selecting Replacement Females
18
Boar Selection

• Extremely importance for genetic improvement
• Contribute of the genetic
  composition of the herd
• Boars need to be from highly productive dams

19
Crossbreeding from Commercial Swine Producers

• Select for economically important traits
• Crossing two or more breeds increases
  productivity
• Hybrid Vigor

20
Crossbreeding from Commercial Swine Producers

• Know the strengths and weaknesses of each breed

21
Crossbreeding from Commercial Swine Producers

• Rotational Cross
• Terminal Cross

22
Developing F1 crosses
Yorkshire
Hampshire
23
Developing F1 crosses
Duroc
Hampshire
Terminal Boars
24
Crossbreeding from Commercial Swine Producers
25
Crossbreeding from Commercial Swine Producers
26
Crossbreeding from Commercial Swine Producers
27

• Chapter 29 Swine Selection and Life Cycle
• Know the main swine traits and how they are
  measured.
• What ways can we evaluated performance records?
• What are important characteristics of replacement
  gilts?
• What are reasons that a sow should be culled?
• What traits are important in a boar besides
  reproductive soundness?
• Why is crossbreeding a good mating system?
• Explain the types of crossbreeding systems.