During recent discussions involving production systems and contract growers, the focus was on how to improve feed conversion in growers’ facilities. For owners, ingredients, particle size, diet sequencing, antibiotics inclusion, Paylean use and such are all important.

However, for growers such decisions are meaningless, as they feed what is delivered. Their challenge is how to get the best pig performance out of that feed.

For contract growers, the feeder is the point at which they control feed expenses. So, let’s do the math on how much feed goes through a typical feeder in a year. Start with a grow/finish facility that turns 2.8 times annually. Pigs typically arrive weighing 55 pounds, with an average market weight of 270 pounds, which means they gain 215 pounds in the facility. If feed conversion is 2.8, it means the pig consumes 602 pounds of feed.

For 40-foot-wide facilities, typical pen densities run 25 to 27 pigs, with two pens of pigs per fence-line feeder. Take 52 pigs x 602 pounds of feed per pig x 2.8 turns = 43.8 tons of feed per feeder per year. With 33 pigs per pen in a 50-foot-wide facility, that grows to 55.6 tons per feeder annually.

For single-stocked, wean-to-finish pigs that arrive at 12 pounds, with a sale weight of 270 pounds and a 2.25 feed conversion, the feed usage is 658 pounds per pig. If the facility turns twice annually, the feed passing through each feeder in a 40-foot-wide facility is just over 34 tons. For a 50-foot-wide facility, that number grows to 43.4 tons per feeder annually.

So, each feeder is really important to controlling feed expenses. If the average ton of feed delivered this year is $200, it means each feeder controls $8,760 worth of expense in 40-foot-wide grow/finish facilities and $11,200 in 50-foot-wide facilities.

Since the mid 1990s, average market weight has greatly increased, which means the pig’s head and shoulder dimensions have increased. A feeder with a 12-inch space is no longer adequate for pigs pushing 300 pounds. In nurseries, the typical 6-inch-wide feeder hole limits feed intake once pigs reach 40 pounds. Here is a look at shoulder dimensions for growing pigs:

Pig weight (pounds)    Shoulder width (inches)

                44                           6.8

                66                           7.7

                242                         11.9       

                264                         12.2

                297                         12.7

To define feeding space, increase those dimensions by 10 percent to allow room for movement at the feeder. This means a 50-pound pig uses 7.8 inches of space when it stands at a feeder; a 260-pound pig uses 13.7 inches; and a 286-pound pig uses 13.9 inches of space.

So, how many feeders installed in the 1990s now limit feed intake due to changes in pig dimensions?

Because feeders are major capital expenditures, when should contract growers be required to replace feeders? Also, what type, brand or model are they required to install? Unfortunately, there’s limited published information that can guide such decisions.

In the 1970s and 1980s, Stan Curtis led research at the University of Illinois on pig eating behaviors and critical dimensions. It led to major changes for farrowing-crate feeders. Since then, Harold Gonyou, at Canada’s Prairie Swine Centre, has reported several studies regarding critical dimensions for pig feeding behaviors at feeders. Kansas State University’s swine nutrition group recently compared a wet/dry feeder to a 10-year-old dry feeder. Beyond this, public research in North America has been limited.

The Europeans have been more active. However, because their slaughter weights are 30 pounds to 40 pounds lighter than ours, translating the results to U.S. production is limited.

Many production systems now invest in private research facilities. As many readers know, I’m involved as science director for four such facilities in southern Minnesota. We’ve had many discussions regarding feeder trials. One question that immediately arises is, what feeders do we want to compare? Do we compare a new wean/finish dry feeder with a new alternative design or with a 10-year-old design? Do we compare a wet/dry feeder with a new alternative, and so forth? 

If the object is to determine feeder replacement in existing barns, it doesn’t make sense to compare new feeders, because the data won’t relate to current feeders. But, if the goal is to provide data for new facilities, this comparison is valid. If the goal is to compare possible replacement feeders to older feeders, the research site would have to locate enough old feeders to install.

As you can see, while feeders are the control point for the largest single pork production expense, our current knowledge is limited. Too often, feeder-purchasing decisions are based on price without enough consideration to the effects of design or dimension on overall feed usage. In the end it robs from pig performance.