Brown relates steps to keep ensiled forage losses to minimum
In this new era of expensive forages, farmers need to find ways to prevent "shrink" losses in their bunkers and storage systems if they want to remain profitable.
Troy Brown, a forage quality consultant, said these losses can occur as a result of poor management practices at feeding time, during storage or at the time the feed is mixed and delivered to cows. Each time-frame in the process presents an opportunity to prevent some of those losses.
Brown, a national consultant for Cargill Animal Nutrition, is headquartered in Reedsville and was a featured speaker Tuesday (Jan. 22) during the annual symposium sponsored by the Midwest Forage Association (MFA) in conjunction with the Wisconsin Custom Operators (WCO) and the Professional Nutrient Applicators Association of Wisconsin (PNAAW) in Wisconsin Dells.
The cost of corn silage last fall was driven as high as $70 per ton standing in the field - an instance he knew of in New York - which makes the cost of shrink and feed losses significant.
Losses can come at a number of stages in the forage process. That includes a number of areas where management can be brought to bear to make improvements - delayed harvest due to weather or equipment problems, poor storage facility design, mechanical problems with merging or raking, fermentation, surface management, wind, rodents and birds and bunker seepage.
Management of the various things involved in harvesting, storing, handling and feeding forages will determine if losses rank in the single digits up to 62 percent or even higher.
Brown, who grew up on a dairy farm in southern Minnesota and attended the University of Wisconsin-River Falls, spoke passionately about forage during the two-day symposium. He has been a forage consultant for 25 years.
One of the ways farmers can monitor feed losses is to keep track of temperature in their silage. There will be heat from normal plant respiration during ensiling process and then normal fermentation will take place at temperatures from 90-110 degrees.
Once it is ensiled and fermentation has been completed, it can be helpful to monitor temperatures to prevent more loss. "It should not begin to heat up above ambient temperatures," Brown said.
"If secondary heating occurs, the primary culprits are yeast and molds. That's very undesirable."
Over 90 percent of the yeast population is made up of lactate-consuming organisms, he explained. As the pH of the feed rises, yeasts and then molds are given the opportunity to grow on the feed.
Brown mentioned that one management factor that can easily lead to this is facing the bunker silo and then letting the feed sit there for extended periods. Uneven or jagged cuts on the face of the silage pile can lead to air infiltration, which is the enemy of good, efficient feed storage.
If feed didn't get packed tightly enough or covered well enough along side walls or other areas, that provides another opportunity for mold to develop and losses to occur. Good feed managers will fork away and discard those moldy areas rather than feed it to their cows, he said.
Knowing where heating is occurring can be a first step toward preventing some of those losses, he said. "There are inexpensive tools to measure forage heat like data loggers to more expensive tools like thermal imaging cameras that are becoming more popular."
In the case of one farm he worked with feed was being delivered from another location and sat there heating to 128 degrees. For that farm, preventing those losses was as simple as making the change to daily deliver and using the feed quickly.
Another case he mentioned involved losses in a drive-over pile of silage that didn't have any bunker side walls. Surface temperatures showed that the farm was losing a lot of heat.
"Basically they could have bought a lot of concrete for the feed they were losing. It was in excess of 50 percent. It was a train wreck."
Some solutions are even easier to accomplish. "Keeping the feeding area clean and organized in such a way that air isn't introduced into the feed can prevent a lot of losses."
One farmer he worked with had an employee mixing feed who didn't want to get to work as early as he needed to in order to face the silage pile and then mix the feed in time for a given feed delivery period. So he faced the pile before he left in the evening.
Brown determined the amount of heating that was occurring in that feed as it sat on the bunker floor overnight for mixing the next day and calculated the losses. The solution in this case was simple management - clean up the feed into which air had been introduced. That solved the waste problem.
Even in cold climates, like one of the farms he consulted on in Idaho with minus-20 degree temperatures and wind chills, loose feed lying on the bunker floor heated to 104 degrees.
"Even in winter you have to worry about this."
The reason farmers need to worry about this heating? A 30-degree temperature rise in the feed burns up 13 megacalories of energy, stealing some of the carbohydrates and sugars.
"The longer the heating remains, the greater the losses."
That 30-degree rise in temperatures represents a minimum of 40 pounds of milk that is not going to be produced when cows eat that feed, he said.
Brown encouraged farmers to think about the difference between forage shrink and dry matter shrink. A low feed shrink loss can be a large dry matter loss, he said. Dry matter losses at 10 percent can be handled, but as losses mount to 20 or 30 percent they run into serious money at the current price of corn silage.
With the sky-high price of alfalfa, dry matter losses there are even more striking in that forage, he added.
STEPS TO IMPROVE
One of the first ways to improve feed efficiency and prevent dry matter losses in ensiled forage is to pack the feed tightly and raise the "density score" of the feed - a measure of how well it is packed.
Brown said a "low porosity" score is another way to look at this. Farmers need to look at placing 800 pounds of packing weight on every ton put in the bunker per hour. For tight compaction, layers of feed need to be six inches or less as they are spread and compacted on the pile.
"Thicker layers reduce the effectiveness of the packing weight."
While it would be really impractical to slow down the harvest to achieve the best packing possible - typically packing is the bottleneck of the operation - that would be one way to make improvements. However, more practical ways would be to add weight, put more tractors to the task or use larger tractors.
"You need to focus on the packing procedures. The most important guy in the process is the guy in the packing tractor," and generally that's not the case, he said.
"Typically it's the new guy, the guy with the least seniority because nobody wants to do that job or it's the guy that tears up equipment because you don't want him in the chopper. But this is a very, very critical job to the success of making good forage."
Getting an effective seal on the silage is another great step to save feed. While it's not always humanly possible to seal the bunker as soon as the packing operation is done, that is the best case scenario.
"A seven-day delay in sealing nearly doubles the storage losses," he said.
Some farmers are using two layers of plastic or thin, non-permeable plastic sheets to cover their bunkers. There are also new alternative tireless systems that are finding favor with some bunker owners.
Some farmers are using plastic down the sidewalls of their bunkers as well to prevent forage losses.
Using a high-quality feed inoculant is another way to achieve forage savings.
Research has proven that inoculating feed with a microbial product allows forages to get faster, more efficient fermentation and produce more lactic acid. It improves dry matter recovery, forage quality and aerobic stability while improving animal performance 3-5 percent when it gets fed.
After that, managing the exposed forage during feed-out is the next step to achieve savings. The rate that feed is removed should match the amount that is needed to feed the herd to keep any loose feed at a minimum.
Brown spoke of silage avalanches that have occurred in the state, showing photos of piles and bunkers that were left in some precarious positions and were accidents just waiting to happen.
Some of these farm accidents have caused serious injury, including paralysis and broken backs to farm workers who were in the way. In other cases only equipment has been damaged and even those instances looked scary.
Farmers with big bunker piles need to discuss drive-over and feed-out systems and procedures with their team.
"This isn't really about shrink loss, it's about sending home your employees to their families each and every day."