Typically when we hear the phrase “food vs fuel”, it’s in regards to ethanol production. However, with the dramatic increase in propane costs recently, many pork producers are wondering if it’s more profitable to turn down the thermostat a little and use more feed instead of keeping room temperatures at their current levels.
The pig is incredibly adaptive to its environment, and can compensate for changes in thermal environment by a variety of ways, the biggest probably being changes in feed intake. As can be seen in the graph below, a pig’s feed intake is directly related to the temperature of the pig’s environment. As the temperature gets colder, a pig will eat more feed in order to generate more body heat to stay warm. As long as gut fill isn’t an issue, daily gains should be normal, but feed efficiency will suffer because the extra pounds of feed are going into heat production and not into body growth.
Basically, it comes down to whether the extra calories from feed are cheaper than the cost of the propane needed to keep the pig in its thermal neutral zone. With corn at $4/bushel, soybean meal at $450/ton and propane close to $4/gallon, utilizing more feed calories is something producers should at least consider.
A collaborative trial done by the University of Minnesota, the University of Nebraska, the University of Missouri-Columbia, and South Dakota State University looked at the effects of reducing nocturnal temperature of early-weaned pigs (17-21 d) in colder months. The first week post-weaning, both rooms were kept at identical temperatures. However, one week after weaning, the temperature in the Reduced Nocturnal Temperature (RNT) room was dropped 10oF from the Control (CON) between 1900 and 0700 hours, and then returning to CON temperatures from 0700 to1900 hours. Pig performance and utility usage were measured throughout the trial. There were no differences in pig gain, feed intake, or feed efficiency for the 28-d period, but heating fuel use (BTU/pig) was reduced by 17.4% and Kwh/pig was reduced by 10.7% for the pigs in the RNT treatment. Using $5.00/gal for heating fuel price and $.08/Kwh, this equates to a saving of $2.90/ pig in heating fuel and $.05/pig in electricity. This results in a total saving of $2.95/pig in utility cost without affecting pig performance.
The other area where temperature reductions could work is in gestation barns. Sow are limit-fed during gestation to maintain proper body condition so dropping the thermostat slightly should not hurt sow performance as long as there is an increase in feed offered to the sows. Work by Verstegen and Curtis (1988) demonstrated that decreasing room temperature by 4 degrees below thermoneutral conditions will require approximately an extra ½ pound of feed/day/sow. With gestation feed at $200/ton, that would be an increase in feed cost of $.05/sow/day. Producers would then need to balance that cost against the propane savings in their individual barns. Management also plays a role in this decision. To properly adjust all the feed drop-boxes takes time, so that is an additional cost that also needs to considered in the equation. In general, it would probably make more sense to adjust feeding levels in November when we’re going into winter than at the end of February where we are going into a period of warmer weather for gestating sows.
Higher propane costs do present a challenge to pork producers, but there are things producers can do to compensate for it. Management tools like reducing nursery room temperature at night will not affect pig performance but can save producers almost $3/pig in utility costs. Going into an extended cold period, producers should also weigh the costs and benefits of lowering gestation barn temperature while increasing feeding level.