Issues to Consider in Marketing Heavier Hogs

Increasing market weight is a change in the whole production system. There are many factors to consider before adjusting market weight targets on-farm - get all the facts. Consider the following questions and their implications:

1. How much extra feed is required?

• depends on many factors and will vary dramatically between farms
• a University of Illinois study has shown that increases in slaughter weight of modern, high-lean genotypes results in minimal changes in feed efficiency
• assuming a feed conversion of 3.79 for finishing pigs (based on NRC Nutrient Requirements of Swine), it would take about 46 kg of feed to raise pigs from 102 to 114 kg (225 to 250 lb.)
• assuming $250/tonne of feed (Pork News & Views, November/December '97), this translates into $11.50/pig to raise pigs from 102 to 114 kg
• the University of Illinois study determined that high-lean genotype pigs consumed an extra 10 g of feed/day for every kg increase in slaughter weight
  
  

2. How should the diet be formulated?

• feed intake and lean deposition rate will influence the nutrient requirements of the late finishing pig

• formulation should be based on feed intake to ensure that adequate nutrients are supplied - i.e.: it is essential to know actual feed intake

• some pigs decrease feed intake after 91 kg (200 lb.) - i.e.: gilts generally eat less during estrus

• a phase-feeding program is ideal to minimize over-formulation of nutrients

• detailed knowledge of the lean growth pattern and muscle mass of finishing pigs is essential to determine the changing amino acid requirement of the late finishing pig - this is primarily a function of the genetic strain

• consult a qualified nutritionist to formulate an appropriate ration for late finishing
  

| Top of Page |

3. How much additional space is required?

• the Recommended Code of Practice for the Care and Handling of Pigs shows space requirements (in m2/pig) for pigs are determined by the equation:
  Coefficient x BW 0.667
  where the coefficient changes according to the type of floor (0.035 for fully slatted, 0.039 for partial slats, 0.045 for solid bedded) and BW is the bodyweight of the animal (kg)

• pigs housed on fully slatted floors and marketed at an average weight of 102 kg would require maximum 0.77 m2 (8.5 ft2) compared to 0.82 m2 (9.2 ft2) at 114 kg -this represents 8% more floor space for the heavier market hog

• a study by the NCR-89 Committee suggested that growth rates for slaughter pigs at 113 kg were maximized at a space allowance of 0.93 m2 (10.3 ft2)

• recent studies at University of Nebraska determined that high-lean genotype pigs derived little benefit from increased space beyond 8 ft2

4. Will the facilities work with heavier pigs?

• adequate feeder size and space, and drinker height are essential to ensure that feed intake is not limited
• pen height may be too low in some facilities to accommodate larger pigs
• modifications may be necessary to provide adequate ventilation for heavier pigs
• animals raised to heavier weights spend a longer time in the barn - as a result there are fewer turns/year
• assuming pigs, on average, maintain a growth rate of 850 g/day, heavier pigs will take 15 additional days to reach market weight at 114 kg vs. 102 kg
• the University of Illinois study determined that high-lean genotype pigs required an extra 1.2 days to reach market weight for every kg increase in slaughter weight
  

| Top of Page |

5. Will transportation needs change for heavier pigs?

• there is no data to suggest whether or not trucking requirements change with increasing body weights however common sense suggests some modifications in density would be necessary

6. What effect will heavier carcass weights have on cost of production?

• keeping pigs longer will increase inventory costs as barn turnover decreases
• feed costs/pig will increase
• a cost benefit analysis is essential, taking into consideration any premiums available and the associated cost of raising pigs to heavier market weights

7. How will genetics perform at heavier market weights?

• knowledge of the genotype is essential - will the pigs remain lean and feed efficient when taken to a heavier market weight?

8. Will heavier weights change health status?

• there is no evidence to suggest that health status will be compromised with heavier market weights
• if mitigating factors such as overcrowding, poor ventilation, or other factors result from keeping pigs to heavier weights, additional stresses may lead to secondary problems such as disease, tail-biting, etc.