Project Summary

Each group was weighed going into the finishing units. Feed consumption and days on feed were tracked. The feed conversion, rate of gain, and carcass data of the two groups were compared. By comparing the dollars received in each system with the dollars spent to build each building, we computed the profit of each building and dollars returned to the operator.

Project Description

My wife, Judith, and I farm 500 acres nine miles southwest of Preston in southeast Minnesota. We live in country that has rolling terrain that is dominated by Fayette soil. We rotate corn, soybeans, and alfalfa in a minimum tillage system. We finish 2,600 hogs and have 20 beef cows. Jud and I are the main labor source; we do hire part-time help during spring planting and fall harvest seasons.

We have information from Iowa State University about the performance of hogs in hoop barns vs. slatted barns but our winters are more severe here than in central Iowa. We need hard data on performance of pigs split into two groups; one in hoops and one in slats. We know that hoop barns cost less to build but we need to see if the savings transfer this far north.

We planned to divide groups of about 500 single source pigs into two groups – one subgroup into the hoop barn and the other into the slatted barn. This was an attempt to limit as many variables as possible from the study. We had a three-year contract for a single source of early weaned pigs prior to entering this study. The person on the other side of the contract decided to break the contract, so the first group was a different source than later groups but with the same genetics. After the problem with our source, eight neighbors formed a limited liability partnership and we purchased sows of the same genetics to supply all of us from the same farrowing unit. Since we now own the sows, there will be no change in the source.

Each group was weighed going into the barns with food consumption and days on feed tracked for the time they were in the barns. After slaughter, we calculated feed conversion and rate of gain, and also compared carcass data. At the end of the three year project, we calculated three year averages for rate of gain, feed conversion, days on feed, value of carcass in each system, and dollars returned per dollars spent in each system.

Results

We have had five turns of the finishers at this point. Even after three years, it might still be too early to make any definitive conclusions about the two systems. A flare up of PRRS (Porcine Reproductive and Respiratory Syndrome) in the sow herd that supplies our finishing barns could have affected the pigs in the study. The close-outs from the comparison of finishers from the five groups showed that the pigs in the slatted barn outperformed the pigs in the hoop barn for two groups, the hoops outperformed the slatted barn for two groups, and performance was poor in both barns for one group. Some of the close-out data is shown in Table 1. The rate of return on investment calculation is another way of comparing financial performance of the two systems.

After the first group, we refined the software program that we use to track pig performance. We added rate of return on investment, annualized profits, and barn turn over rate. The hoop structure is a good place to use the straw created from the nurse crop for alfalfa. Prior to construction of the hoop barn, using the straw was a problem. We are very happy that we decided to pour concrete side walls instead of using tongue and groove lumber. These are much more durable when you clean the barn and pigs cannot damage concrete by chewing on it the way they might damage wood. We made our own forms which made the cost comparable to wood walls.

We encountered a number of health issues during this project. With the disease problems we experienced in 2003, I wondered if I was leaving disease behind when I cleaned the bedding out of the hoop barns in the winter, or if the manure pack heated up enough to kill disease organisms. With the slatted floor finisher, we power wash when we move a group of pigs out, leaving little chance that disease organisms survive. In 2004, the last group of pigs we put in the nursery in March arrived with Strep. They responded well to antibiotics but all the pigs became sick again a few weeks later when PRRS showed up. We began to experience large death losses in the nursery so we moved half of the pigs to the slatted finishing barn earlier than planned to give all the pigs more room. Death losses continued there totaling about 14% between the nursery and the finisher. The rest of the pigs were moved to the hoop finisher two weeks later. This group also experienced about a 14% death loss with most of that occurring in the nursery which was not reported in Table 1.

Another possible disadvantage to the hoop barns is the stress put on animals being moved from the nursery to the hoop barn when there are wide temperature differences. We had a 30ºF temperature swing in 24 hr when one group was scheduled to move to the hoop barn. We delayed moving them until the temperature had moderated. I have also decided not to use “cold confinement” systems in January and February because of gates freezing down and the stress on small pigs started during the coldest part of the winter. One problem to be aware of is that slatted finisher barns are fully insurable for wind and fire damage. Hoop barns are not insurable for wind but are insurable for fire. There is, however, greater risk of suffocation in slatted finishers and it can be costly to insure against that.

Management Tips

1. The hoop barn is a good place to use up the oat straw created from the nurse crop for alfalfa.

2. To avoid stressing the pigs, consider waiting to move pigs from the nursery to hoop barns if the weather is bad and there are wide temperature differences.

3. Consider pouring concrete for the side walls. It is much more durable when you clean the barn.

4. Make the notch at the top of the wall 2” by 8” at a minimum but 3” by 10” would be best for air flow. We used a 2” by 6” and found that the tarp covered too much of the slot, reducing airflow.

5. I am convinced that I could have saved money on the hoop structure by not putting in the side rollup vents. I didn’t need them where I have the barn. You may want to include them if you are in a valley or surrounded by trees where airflow is a problem.

6. Use 5’round bales or 6’square bales for bedding. One person can roll these sizes without using a loader in the hoop barn. This size square bale rolls just as easily as the round bale.

Source: Minnesota Department of Agriculture - June 2006