Fermentation bedding culture is added to bedding at the start of a batch and works by turning the bedding into a stable, actively fermenting system rather than an accumulating pile of manure and urine. The culture speeds up the initial establishment of the bedding microbial community, and because the bedding is kept warm and slightly acidic, ammonia release stays low. It works well where the barn is well managed and it does very little where bedding is removed before the culture has established, which is the single most common reason for a disappointing result.
Product referenced in this article
Bacteria for Fermentation Bedding — application notes, specification table and document downloads for this range.
What the bedding actually is
Conventional bedding is an accumulating mixture. Urine adds nitrogen, faeces add both nitrogen and organic load, and the material is removed only every few days or weeks. Early in that cycle the bedding is warm, wet and anaerobic, which is the worst combination for odour: the microbial population that is producing the strongest odours is the one that thrives in those conditions. Deep litter systems work the other way round. The bedding is deliberately kept thick, warm and aerated, and the population established in it is one that processes the incoming material quickly, so the bedding behaves as a working reactor rather than as a store.
Culture is what starts the reactor. The bedding itself already contains microorganisms, but the population that establishes depends on what arrived with the animals, on the bedding material and on the temperature and moisture history. Adding a culture shortens the time needed to reach a stable community, and in the cold months that shortening is the difference between a bedding that works and one that does not have time.
What the fermentation actually changes
Three things change, and they are worth separating because they have different time scales. The odour profile changes because the organisms that break down organic material anaerobically, and produce the strongest sulphur notes, are outcompeted by organisms that work aerobically and produce far less offensive by-products. Ammonia release falls, because microbial activity in a well-established, slightly acidic aerobic bedding converts nitrogen through a pathway that releases less free ammonia. The bedding becomes easier to handle, because the material is structured and drier at the surface than the equivalent untreated pile.
The ammonia effect is the one most often measured, and it is the one most often attributed to the culture when the ventilation is doing most of the work. A barn with poor ventilation will show an ammonia problem whether or not a culture is present, and a culture will not fix it. Ventilation is the primary control; bedding culture is the second control that makes the ventilated air acceptable.
Establishing the culture: the first three weeks decide the result
Establishment is a short window and it is where most failures happen. At the start of a batch the culture is added to bedding that has already been used, or to fresh bedding with the first animals arriving, and the population needs warmth, moisture and time to establish. During that period the barn is at its most anaerobic and its odour is at its worst, because the old community is being displaced.
Three practical points follow. First, the culture is a seeding, not a treatment: it establishes a population and then that population maintains itself, so a single addition at the start of the batch is the correct dosing, not a weekly top-up. Second, the bedding must stay damp rather than wet. Waterlogged bedding goes anaerobic regardless of what has been added to it, and this is the most common cause of failure we are asked about. Third, removing and replacing bedding partway through a batch removes the established community with it, so a batch is a batch and should be run to its natural end.
What a culture does not do
It is worth stating the limits plainly, because the claims made for bedding products in general are broader than the biology supports. A bedding culture does not disinfect. It does not sterilise, and we do not describe it as doing so, and we do not publish sterilisation or disinfection figures for it. It does not remove the need to keep the barn clean, to manage wet areas where water sits, or to control the spillage of urine from a poorly designed drinker.
It also does not solve a ventilation problem, and specifying a culture for a barn whose air is not being exchanged is a common and expensive mistake. If air movement at animal level is inadequate, no bedding treatment will bring ammonia to a limit that the animals tolerate.
How to run a trial that produces a usable answer
If the product has to be justified rather than tried, the trial should be designed so that it can fail. Two comparable pens, one with culture and one without, same bedding material, same animal numbers, same management, over one full batch cycle. Measure ammonia at animal level at the same time of day, and record it rather than relying on a subjective impression, because odour adaptation makes subjective assessment unreliable in a way ammonia readings are not.
What we can commit to on a trial is supplying the culture, the dosing guidance for your bedding depth and the measurement protocol, and reviewing the results with you afterwards. What we cannot commit to is a reduction figure for your barn, because the result depends on bedding management and ventilation as much as on the culture, and a supplier who guarantees a percentage without seeing the barn is telling you something about their confidence rather than about the biology.
Frequently asked questions
- How long does a bedding culture take to work?
- Establishment takes roughly the first two to three weeks of a batch, during which the odour may be no better and occasionally worse while the new community displaces the old one. The stable phase follows and persists until the bedding is removed. This is why a trial shorter than one full batch cycle tells you very little.
- Do you add bedding culture every week?
- No. The culture is a seeding step, not a weekly treatment. It establishes a microbial population in the bedding, and that population then maintains itself through the batch. A single addition at the start of a batch is the intended dosing; repeated addition is unnecessary and is not what the product is designed for.
- Can bedding culture replace barn ventilation?
- No, and specifying it as a substitute is a common and expensive mistake. Ventilation is the primary control for ammonia in a livestock building; bedding culture is the second control that makes adequately ventilated air acceptable. In a barn with inadequate air movement at animal level, no bedding treatment will bring ammonia down to a level the animals tolerate.
- Is a bedding culture a disinfectant?
- No. It works by establishing a microbial community that processes the incoming material, which reduces odour and ammonia release. We describe it that way and we do not describe it as sterilising, because that is not what the mechanism does. It also does not replace cleaning, and it does not address water sitting in wet areas or urine spillage from poorly designed drinkers.