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Top Quality Commercial Market Hogs and Champion Show Pigs, Are They the Same?

Livestock Update, May 2004

Allen Harper and Cindy Wood, VA Tech Tidewater AREC and Dept. of Animal & Poultry Sciences

Based on the calls and inquiries coming in, the season for local and regional youth swine exhibitions is upon us. In some areas of the state, 4-H and FFA participants already have project pigs under their care with a local show date just a few weeks away. Others are just getting ready to obtain project pigs and their show date is months away. All have hopes of driving a champion pig, or at least a class winner, into the ring. In my view strong competition at youth swine (or other livestock) exhibitions is healthy and educational, as long as the events are well organized and performed within a framework of integrity and sportsmanship. As we move into this year's show season, it helps to remind ourselves where the focus needs to be in terms of producing and exhibiting top quality market hogs.

Market hog show judges have a very difficult task. Through careful observation they have to determine in rank order the best market hogs in a series of classes. Two of the most important criteria they must look for in performing this task are leanness, as indicated by low external fat depth (backfat), and muscle depth, as exhibited through expression of large, well defined muscle patterns through the loin, shoulder and ham.

These two judging criteria are legitimate, because over the past 15 years the commercial pork industry has placed much greater emphasis on reducing external fat depth and increasing muscle depth. In fact, most commercial packing companies now pay producers based on carcass weight, not live hog weight; and the price for the carcass is increased when there is less backfat depth and more loin muscle depth. There are different instruments used by packers to determine these traits in the carcass but many use an optical probe also referred to as a Fat-O-Meater. The Fat-O-Meater instrument is used to objectively measure fat depth and loin muscle depth near the tenth rib location on each processed carcass.

There is an interesting but predictable trend about show pigs. If judges select the leanest, deepest muscled pigs as class winners and champions, then youth exhibitors will respond by trying to obtain and produce the leanest, deepest muscled pigs possible for their project. A legitimate question is can pigs be too extreme in terms of reduced fat depth and increased muscle expression and depth? One way to approach answering this question is by reviewing the carcass price matrix of a major packer that purchases thousands of commercial market hogs daily and a significant number of the pigs from youth exhibitions in Virginia and North Carolina.

Table 1 presents a portion of the backfat price matrix for various carcass weight ranges for the Gwaltney of Smithfield Packing Company. Space only permits showing a portion of the matrix. Down the left column are selected carcass weight categories. Dressing percentage for hogs is usually about 74%, so an estimate of live hog weight can be obtained by dividing carcass weight by a factor of 0.74. Along the top row are different backfat depth categories which are presented in millimeters (mm). For reference purposes there are about 25.4 mm in an inch.

Table 1. A Selected Portion of the Carcass Weight and Backfat Depth Carcass Pricing Matrix for Gwaltney of Smithfield.

 Backfat Depth
Carcass Wt., lbs. 10 mm 11 mm 12 mm 13 mm 14 mm 15 mm 16 mm 17 mm 18 mm
139-145 88.0 88.0 88.0 88.0 88.0 88.0 88.0 88.0 88.0
146-152 94.0 94.0 94.0 94.0 94.0 94.0 94.0 94.0 94.0
153-159 99.0 99.0 99.0 99.0 99.0 99.0 99.0 99.0 99.0
160-166 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0
167-173 100.5 101.0 101.0 102.0 102.0 104.0 104.0 102.0 102.0
174-180 101.0 103.0 103.0 104.0 104.0 105.5 105.5 104.0 104.0
181-187 102.0 104.0 104.0 105.5 105.5 107.0 107.0 105.5 105.5
188-194 101.0 103.0 103.0 104.0 104.0 105.5 105.5 104.0 104.0
195-201 99.5 101.5 101.5 102.5 102.5 104.0 104.0 102.5 102.5
202-208 98.5 100.5 100.5 101.5 101.5 103.0 103.0 101.5 101.5
209-215 97.0 99.0 99.0 100.0 100.0 101.5 101.5 100.0 100.0
216-222 93.0 95.0 95.0 96.0 96.0 97.5 97.5 96.0 96.0
* Values represent percentages of the base carcass price.

The values represented in the matrix are percentages of what the base carcass price is for any given day. For example if the base carcass price is 66 cents per lb. and the scale and optical probe indicates that a carcass weighs 170 lbs. and has 17 mm of backfat, then the actual carcass price is 102% of 66 cents or 67.32 cents per lb. The highest price per lb. for a carcass is achieved for carcasses ranging from 181 to 187 lbs. (about 245 to 253 lbs. live weight) with backfat depth of 15 to 16 mm (about 0.6 inches). Such carcasses would have an adjusted carcass price of 107% of the base carcass price that day, in other words a 7% price premium. As backfat depth becomes greater than 17 mm the value of the price premium declines. Although not shown here due to space limitations, as backfat gets greater and greater, the price actually gets discounted. For example, a carcass in the range of 181 to 187 lbs. with 30 mm of backfat (about 1.2 inches) receives a price that is only 98.9 % of the base price. Also note that light weight carcasses, especially those weighing less than 159 lbs (about 215 lbs. live), are discounted substantially. Heavy carcasses are also discounted, but not substantially until they go over 215 lbs. (about 290 lbs. live weight).

Of particular interest is the fact that as backfat decreases below 15 mm the amount of price premium becomes progressively less. At 10 mm (about 0.4 inches) or less of backfat depth the carcasses in the desired weight range are essentially at even money with the base carcass price.

Muscle depth is also important in the Gwaltney carcass pricing system. Table 2 shows the price adjustments for different loin muscle depths as determined with the optical probe.

Table 2. Carcass Price Adjustment Factors for Loin Muscle Depth in the Gwaltney Carcass Pricing System.

Muscle Depth < 46 mm 46 - 47 mm 48 - 50 mm 51 - 52 mm 53 - 55 mm > 56 mm
Premium or Discount -2.0% -1.0% 0.0% +1.0% +2.5% +4.0%

Loin depths of 48 to 50 mm get no adjustment in carcass price. Loin depths of 51 mm or greater receive price increases while loin depths below 48 mm receive price discounts.

Based on the packer price matrix the message is fairly clear. Carcasses need to be of adequate weight and underweight carcasses are very much discouraged in the pricing system. It also appears clear that deep muscled pigs are highly desirable and there is no penalty for exceptionally deep muscled pigs. The backfat situation is a bit more complex. Lean pigs with less than an inch of backfat are definitely desirable. The ideal appears to be about 15 to 16 mm. But, as backfat declines below 15 mm (below about 0.6 inches), the external fat depth is becoming less than ideal. The packer is not severely penalizing price on exceptionally lean pigs, but the matrix does send the message that there is a desired minimum and maximum backfat depth.

Back to our original question, are top quality commercial market hogs and champion show pigs the same? "Not exactly" may be the most accurate answer. For example the Grand Champion Single Market Hog at the 2003 Virginia State Fair had some very desirable qualities based on real time ultrasound measurements. A 67 mm loin depth on a 200 lb. carcass would be considered quite desirable. The ultrasound instrument also determined a backfat depth of 8 mm (about 0.3 inches). This was definitely a very lean pig. But, considering the ideal backfat range presented by the packer matrix, such a low backfat depth could be considered extreme. Next month's update will indicate reasons why this degree of leanness may be too extreme along with some ethical considerations for our show pig exhibitors, advisors and suppliers.

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