The amount of faeces that a broiler breeder produces during the production cycle depends mainly on the feed intake, which is roughly 40 kg during the production period (20 to 62 weeks of age). As a rule of thumb, the amount of feed equals the amount of manure when the manure has a water content of 80%*. Knowing this, we would be able to calculate the amount of manure produced during the production period of a broiler breeder if we know the water content of the manure.
However, during the production cycle part of the manure is composting, which means that micro-organisms are converting it into water, Carbon dioxide, Ammonia, other gases, ash (minerals) and heat. By analyzing the content of Phosphorus and Nitrogen in both the feed and the manure, we can estimate the loss of manure by composting as Nitrogen is converted into ammonia and escapes, where Phosphorus doesnt. Research at the Centre of Applied Poultry research in the Netherlands has shown that approximately 30-40% of the manure of broiler breeders is composted during its life cycle, both under the slats and in the litter.
This means that we can estimate the amount of manure produced by a broiler breeder if we correct the initial production of manure by this composting factor.
- If we estimate that the feed consumption is equal to the production of manure with 80% moisture,
- we can estimate that each female is producing 40 kg of manure with 80% water
- 40 kg of manure with 80% water contains 8 kg of dry matter
- if 30% of the dry matter is composted, 5,6 kg of dry matter manure remains
- if this dry matter contains 80% water, the total volume is 28 kg of manure
- if the dry matter is 50%, the amount of water is equal to the amount of dry matter, being 11,2 kg of manure
- if the dry matter is 70%, the amount of manure will be 8 kg per bird
- as normally the dry matter is approximately 60%, a total production of 9-10 kg per bird can be estimated.
* Source: Handboek voor de Pluimveehouderij 1988