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THE IMPORTANT ROLE OF POULTRY MANURE IN COMPOST FOR MUSHROOM CULTIVATIONCreated on 24.04.2019
Chicken manure, popularly known as -Gallinaza- is a good that was scarce a few years ago for composting plants in Spain. There were several reasons for this, among others that the management of it was in the hands of a few suppliers who struggled to establish a kind of monopoly with this product. Fortunately, this situation has now changed, new farms have been integrated as suppliers and there is normally no shortage of supply.
In addition, in recent years, the quality of the poultry has improved exponentially. The chickens are left behind, especially in winter, when they were loaded with humidity, and with a very low nitrogen content, on a bed of straw, forming thick lumps which made it enormously difficult to distribute them.
But forgetting these issues of logistics and distribution of poultry manure, it is interesting to take a closer look at the role of poultry manure in the compost used for mushroom cultivation. Seen from a global point of view, there are not many composting plants worldwide that do not use poultry manure, this shows how important poultry manure is as an ingredient.
Chicken manure has two important functions in mushroom compost. Firstly, it is a cheap and fairly reliable source of nitrogen. In the past, urea, ammonium sulphate, malt cane, cottonseed meal or protein-containing materials were used. However, these are more expensive. What is still seen in some plants where chemical washing of ammonium is done is that the ammonium sulphate released during the chemical removal of ammonia from the process air is added again as a source of nitrogen.
The usual preference is for chicken manure to have a litter of sawdust, rice husk, straw or wood shavings. This fertilizer is quite dry - a moisture content of less than 40% is normal - and easy to disperse. This is very important for a good distribution through the substrate. The chemical composition of manure from battery hens is practically identical to broilers. The moisture content is, however, much higher, so distributing it well through compost is practically impossible, so chicken manure is not used.
The N content of broiler manure in Western Europe is generally around 4%, based on dry matter. This does not include ammoniacal nitrogen which disappears during the drying process with ammonia. The actual nitrogen content is therefore higher.
Nitrogen in compost is important, as it is available in complex forms as a nutrient for fungi (complex rich in lignino-humic nitrogen).
Secondly, chicken manure is full of decomposable carbohydrates. In addition, chicken manure is rich in numerous interesting minerals for compost nutrition. The chicken feed contains various carbon-rich substances that ensure that the temperature increases in the compost, activating the composting process and providing nutrients for the necessary microorganisms. Animal manure also contains many bacteria and other microorganisms with a beneficial effect on the composting process.
Alternatives to poultry manure
If chicken manure is to be replaced, for any reason, two other ingredients are required. For example, urea for nitrogen and molasses for easily decomposable carbohydrates. Other alternatives are a combination of ammonium sulfate and sugar cane residues. Depending on local availability, various alternatives can be used. Cereal straw obviously remains the basic ingredient, and gypsum is also indispensable in mushroom compost.
If animal manure is not used, in a product known as synthetic compost, many valuable types of bacteria that are present in the manure are lost - especially at the beginning of the process. The process then usually takes longer, although urea can still help speed up the start of composting.
In the Dutch situation, horse manure is often used. Making one ton of Phase 1 compost based on horse manure requires about 60 to 70 kilos of chicken manure. Assuming 30,000 tonnes of compost per week in the Netherlands and Belgium, about 2,000 tonnes of chicken manure are needed. With liquid chicken manure this figure is higher due to the high moisture content.
In Spain and other countries, a mixture of chicken straw and manure is frequently used. In this case 250 to 300 kilos of chicken manure are added per tonne of compost Phase 1. This is considerably higher due to the lack of horse manure, which also contains nitrogen.
In the USA, in particular, compost is successfully produced without chicken manure. Various sources of nitrogen are generally mixed to produce a consistent product quality. For example, malt, soybean residues, corn cobs, cottonseed meal and alfalfa meal are used. The reason for not using chicken manure is often a lack of availability and often high transport costs.
Chicken manure recommended
Availability and prices are the main factors when deciding whether or not to use chicken manure. Alternatives are available, but i.e. in Spain, the Netherlands and other countries composting processes are not geared towards their use. In addition, this would make compost much more expensive. Chicken manure blending facilities are generally not adequate to cope with the incorporation of other products, and all new equipment, etc., that has to be purchased to make compost with these other alternative sources of nitrogen, all this at higher prices. This is important because in Spain compost is cheap compared to other countries.
If we work with organic N we can always correct the formula. The moment of application of inorganic N is very important.
Pork manure can be used, but then the dynamics of composting is different. Years ago during the bird flu crisis some plants in Holland and Belgium used pig slurry, although this is also very variable.
- Pork slurry in origin has a content of N = 2,5 %.
- The rest are adjusted in their formulation with ammonium sulphate.
- Chicken manure makes fermentation start faster
- Pork slurry is cold and fatty, so they need ammonium sulphate to start fermentation, if the fermentation is not delayed a week.
In addition to chicken manure, quail and turkey manures are also recommended for composting.Back