Custom feeder's play an important role in the hog industry, and sometimes that role presents challenges that are uniquely difficult for them. For example, Jeremy in Pennsylvania has been feeding hogs for his integrator for many years. However, when feed rations changed and caused unexpected issues in the manure chemistry, the issues that followed caused major disruptions that no one was prepared for. In this case, a picture is worth a thousand words...
The Foam Problem
This gray foam was rising at a rate of 7 inches per week. Numerous pit additives and defoaming products were applied, but nothing worked. The amount of methane producing bacteria in the pit was overwhelming any additive that had been tried. More than $10,000 was spent on this pit, with zero results. Some of the additives even seemed to make the problem worse.
Understanding Why Foam Occurs
Why did this happen? A manure pit is a very complex environment if you're trying to understand all the various microbe and nutrient interactions. However, there are two key factors required for a healthy manure pit: the right set of microbes and some agitation. This pit, pictured above, had a buildup of methane-producing bacteria that eventually snuffed out any of the good bacteria capable of breaking down the solids without producing methane as a byproduct.
Contributing Factors
In some instances, producers will add diesel fuel to knock down the foam. If enough diesel is added, the layer of fuel on top of the surface will cause methane to build up below. This will eventually lead to a rampant foam problem, as the accumulating methane will have to break through the slick surface and fuel foam with even more vigor.
But this pit was fine a few years ago, so what changed? Unless we can account for everything that falls into a pit, it's tough to pinpoint the exact series of events leading to issues like this. However, if a lot of feed falls through slats, and settles at the bottom of the pit, that sediment becomes a source for the foam. Distiller's grains also provide more fuel for foam, as greater amounts of fiber pass through the animals and settle at the bottom of the manure pit.
Pit Design and Agitation
Another factor to think about is how well the pit had been previously pumped out. First, consider how the pit was designed. If the pit is difficult to agitate because the agitators in the pump-outs cannot reach the entire floor of the pit, then troublesome solids can remain and provide a home for solids and methanogens (methane producing bacteria) to build up over time, creating 'dead zones'. Pillars in the manure pit can also create dead zones. This is a problem that exists to some degree in every pit.
The NGA Solution
The pictures below show two of three barns that had an increasing foam problem. NGA was applied in the first barn (photos left and middle), but it didn't work right away. There was simply not enough NGA or agitation for the NGA to take hold fast enough to curb the foam. So a significantly stronger dose of NGA was applied a few days later while the pit was slowly agitated. After a day, the foam stopped growing. Less than a week later, the foam began to drop. The first two photos capture the before and after from the high dose treatment. The third photo is of another barn on site with an emerging foam problem.
In this case, NGA finally solved his expensive problem. Although NGA is most cost-efficient when treating smaller amounts of manure, it does work to stop a severe foam problem quickly. It is better to apply it at the first sign of foam. The best approach, however, is to treat the pit when there are no observable issues. Less product needs to be applied, and less work is required when treating a relatively healthy pit with much less NGA. The old adage comes to mind, an ounce of prevention is worth a pound of cure.
