How the Weather and Feed Shrink Affect Your Bottom Line

Mr. Jason Hartschuh, Crawford County Extension Educator, The Ohio State University Extension

When we think about minimizing feed shrink, we typically focus on forage shrink and forget how quickly concentrate shrink expenses can add up when a dusting is lost here and there. Shrink comes in many forms; field losses, storage, heating, wind, rain, rodents, birds, wet tires, and mixing errors. Concentrate commodities shrink in many ways from the time they arrive at the farm until they are eaten by your cows.

The cost of shrink on your farm can add up quickly. Utilizing the typical shrink values on the average farm feeding a silage-based ration, feed cost will increase by about $0.60/cow/day. If these losses could be decreased by 50%, it could save a farm $100 per cow per year. To realize these savings and reach the goal of a 50% reduction in shrink, it helps to identify shrink of individual ingredients. With just an 8% shrink loss of a $400/ton concentrate that is fed at a rate of 6 lb/cow/day, the losses will be almost $0.10/cow/day (Harner et al., 2011).
How a commodity is delivered and stored and how much wind is blowing each day affect the amount of shrink you may experience. Dry meals that are housed in 3 sided commodity bays have a typical loss of 3 to 8%, while storage in a feed bin has losses of only 2 to 4%. If your losses are at the upper end of these ranges, or unknown, there are a few areas you can investigate. Wind can be a substantial source of shrink with concentrates in either system. When winds are blowing at 10 mph, there is an 8% increase in losses versus 5 mph. At 15 mph, the losses increase by 27%. While winds over 15 mph are not the consistent norm, we often have wind speeds around 10 mph. In order to manage these losses, a few strategies can be implemented. For loading out of a commodity barn, decreasing the distance from the barn to the mixer wagon and providing a wind break at the loading pad can be beneficial. Even with feed bins, some wind shrink may be present as the feed falls from an auger into the mixer. Using drop tubes to get the feed down into the mixer or having your bins set up to load the mixer through a central building that blocks the wind can minimize these losses.

Commodity barns also have a few other sources of losses that should be considered and managed. Two sources of shrink are losses during unloading and moving commodities into bays and rain that enters these bays during storms and causes feed to rot. Many of our commodity bays are tall enough to dump directly into, minimizing losses that occur when feed is dumped outside the bay and pushed in with a loader. Unloading losses are also greater with belt trailers and walking floors than with dump trailers. The tall building to accommodate dump trailers can lead to increased losses from moisture blowing into the shed. Some of this is managed by orientation of the building. Adding a curtain to the barn to close the open portion up some when feed is not being delivered can also be very beneficial. When a barn with a 20 ft opening is closed to a 12 foot opening, the moisture entering the barn is reduced by 40%. If you could close it down to 8 feet, the reduction in moisture entering the building is 60%. The moisture that enters can lead to spoilage and wetter commodities. The wetter feeds throw off the accuracy of your ration when it is delivered to the cows.

The other major shrink error for some producers is scale inaccuracies. Most mixer scales are only precise to plus or minus 10 lb, even if they count by fives. The accuracy error is typically about 1%, but varies a lot between mixers on different farms. An article in Hoard’s Dairyman last fall stated that in a study looking at mixer scales on 22 farms, only half of them worked properly. The challenges for the 50% improperly working mixers came from multiple sources. One error came from lack of calibration when a new scale head was installed on a set of load cells, which caused a consistent error percentage to all ingredients. This came from a partial fix of another common problem, which was worn out weigh bars and scale displays. Another error was binding within the load cells’ mounting system; the binding in these mounts can result from several causes, including rust and caked mud and dirt around them. The error caused by the binding varied by ingredient, being worse early in the mixing and more accurate the fuller the mixer, throwing off the delivered ration more than the uncalibrated scale head errors.

To diagnose an error in your scale system, two options can be used to test your TMR mixer scales. One would be to run across a calibrated truck scale after each ingredient is added for a couple batches of feed. Another would be to find someone with a set of truck pad scales and run each axle of the tractor and mixer over the pads after each ingredient is added. The scale pads need to be set up on a concrete pad with a less than 1% slope for maximum accuracy. You may be able to find a set of truck pad scales by talking to your local feed mill or someone who sells seed and does test plots. With either method, you should weigh multiple batches to get the most accurate comparison for diagnosing any problems.    

Brouk, M. J., and J. P. Harner, III. 2016. Designing Feeding Facilities to Maintain Feed Quality. Tri-State Dairy Nutrition Conference April 18-20. Pgs. 149-58.      

Harner, J.P., J.F. Smith, M.J. Brouk, and B.J. Bradford. 2011. Feed Center Design. Western Dairy Management Conference. Reno, NV. March 9-11. Pgs 91-102.

Rasmussen, J., and E. Templeton. 2015. “Are Your Scales On Target?” Hoard’s Dairyman November 2015. Pg. 738.