Collaborative research conducted at the Agriculture Department's (USDA) U.S. Meat Animal Research Center (MARC) has led to the inclusion of a high-lean growth genetics option in a current swine growth model. The update to the model was completed by the University of Kentucky.

This addition to the model permits producers and researchers to compare the economic impact of changing genetics.

Swine production variables used in the comparison of two genotypes are contained in Table 1. The comparison of production parameters and economic return of a moderate and high-lean genotype are detailed in Table 2.

The MARC research bore out that a high-lean growth genetic line reached slaughter weight 10 days earlier than its moderate-lean growth competitor. This produced a net gain of $1.11/pig prior to inclusion of carcass premiums for percent lean.

The MARC project updates the swine growth model (NCPIG) developed by the North Central Regional Swine Modeling Committee. NCPIG simulates the interactions of feed intake, nutrient digestion, body maintenance, tissue accretion and individual animal response to an environment over time.

Table 2. Economic Comparison for the Simulated Barrows
Item Moderate-Lean Growth High-Lean Growth
Initial weight, lb. 68.47 69.53
Market weight, lb. 244.46 245.04
Carcass weight, lb. 191.72 191.96
Days on feed 94 84
Average daily gain, lb./day 1.87 2.09
Feed to gain, lb.:lb. 2.45 2.41
Total feed intake, lb. 432.32 423.09
Total feed cost, $ 30.26 29.62
Total pig investment, $ 67.10 66.10
Total pig return, $ $92.03 92.14
Net gain/pig, $ $24.93 26.04

Table 1. Swine Production Cost Variables Used as Inputs for Both Genotypes
Fixed Production Costs Variable Production Costs
Initial pig value in facility $20/pig Interest rate 10.0%
Facility without misting- cooling $7/pig Labor 3ยข/pig/day
Operating costs $1.50/pig Veterinary cost $3/pig
Marketing cost $2/pig
Feed Costs Carcass Sale Price
Ration $140/ton Base value $48/cwt.

Researcher: Tami M. Brown- Brandl, U.S. Meat Animal Research Center. Contact Brown-Brandl by phone (402) 762-4279; fax (402) 762-4273 or e-mail brandl@