POULTRY MANURE MANAGEMENT: WASTE TO WEALTH
Poultry manure is the organic waste from poultry composed mainly of faeces and urine of chickens. Poultry litter is made up of poultry manure, spilled feed, feathers and bedding materials. The advantage of poultry manure over other animal manures is that it has the highest amount of Nitrogen, Potassium and Phosphorous. Poultry manure is classified as either solid (when solid content is greater than 20%), semi-solid (contains 5-20% solids) and liquid (when it contains less than 5% solids). To produce solid manure, the liquid must be drained off and manure dried or bedding added.
This rapid growth of poultry industry has created a major problem which includes large scale accumulation of manure which poses pollution of soil, surface and underground water contamination, pathogens and heavy metals. It creates odor and attract flies, rodents and other pests that causes nuisances and carry diseases to people. It also cause public nuisance.
• Effect on land
It contains all the essential plant nutrients that are used by plants which include: Nitrogen, Potassium, Phosphorous, Calcium, Magnesium, Sulphur, Manganese, Chlorine, Zinc, Copper, Boron, Iron, and Molybdenum. The availability of these nutrients can vary depending on factors like age and diet of the flock and moisture content.
It can support crop production and enhance physical and chemical properties of the soil.
It also increases the moisture holding capacity of the soil and improves lateral water movement thus improving irrigation efficiency and reduces the general droughtiness of sandy soil.
It improves soil retension and uptake of plant nutrients.
It increases the number of diversity of soil microorganisms.
It also serves as a soil amendment: It restores deteriorated soil.
• As Biogas
This can be produced by anaerobic digestion of poultry waste. This is a very useful combustible gas with around 60% methane. Biogas can be used for cooking, fuel for engines, to produce electricity and to produce heat by simply burning.
• As Animal feeds
It can be used as feed for cattle and fish. Foreign materials in it have to be removed. Also, to be able to use it as feed, proper processing is a must to eliminate substances like antibiotics, coccidiostats and arsenicals. It also contains proteins, minerals and fiber.
In the USA, solid manure is typically removed using mechanical scrappers and front-end loader while liquid and slurry manure is removed from houses by pumping or by flushing with water. Most poultry manure is used for crop and pasture fertilization as a cost-effective alternative to inorganic mineral fertilization. Also, liquid manure from layer operation can be stored and treated in anaerobic lagoons and the supernatant recycled for flushing layer houses and irrigated as a source of nutrient and water for plants. Also, it can be used to produce biogas which is then converted to electricity. A small portion of the litter and straw may be used as a carbon source for animal mortality composting with the resulting compost used as fertilizer. Broiler litter/dried layer manure is also used in the microbial mixture to supply nutrients for Agaricus Mushrooms.
TYPES OF WASTE SYSTEM IN NIGERIA.
• Deep Litter System: Broilers and turkeys are often raised on litter for at least part of their lives. Breeders and pullets are raised on litter in many cases. Any clean, absorbent material can be used for litter such as wood shavings, shredded paper products or sawdust if available. The litter should be dry and should not produce excessive amounts of dust. The floor should be covered with fresh litter material prior to the housing of each new flock of birds at a recommended depth of 4 to 8 cm (1.5 to 3 inches). The litter removed from the building must be stored in a suitable storage structure.
• Cage House, Deep and shallow Pit System: The deep pit offers operational advantages over other systems. For example, a separate manure storage facility is not required. In this system, manure is allowed to drop into a 1.5 mto 3.0 m(5 to 10 feet) deep pit under the cages where the droppings undergo a natural composting drying process. This causes a biological degradation of the wastes and reduces the weight and volume of the manure. The success of the pit depends on the extent to which excess water can be excluded. If the manure is wet, the composting process will not occur, resulting in odours, fly problems and the need for frequent cleanouts. If properly operated, a deep pit may not require cleaning for one to three years depending on the depth of the pit. This is an easy system to manage and requires only a front-end loader and a conventional manure spreader to clean out the pit.
For cage House, Shallow Pit System: This system uses a concrete pit 15 cm to 20 cm (6 to 8 inches) deep to collect the droppings from overhead cages. The manure is allowed to collect for a short time, preferably not more than one week, and then it can be scraped out.
• Cage House, High-rise system: The house is raised by 6-7 feet by concrete pillars. Two feet wide concrete platforms are made over the pillars. The cages are then built on slotted flooring 8 feet or more above the pit floor. Natural composting occurs in this type of waste system. Manure can be stored for several months before removal. This type of house provides sufficient ventilation in tropical countries.
CONVERSION TO WEALTH
Deep litter waste
The waste that is generated is always dry and is composed of faeces, urine of chickens, spilled feed, feathers and bedding materials such as wood shavings. At the end of the rearing period, the dry litter is packed and bagged in 100kg sacs. Cost of a bag (100kg) in Ibadan ranges from #300-#400
Cost of a bag (100kg) in North ranges from #3000-#3500
For shallow pit, faeces are raked or scraped using manure scraper and flushed into the storage facility. Then it can be dried using manure drying machine or dried naturally and bagged in 100kg sacs.
For deep pit/high rise, manure is removed once or twice in a year so the moisture content would have been reduced at the end of the rearing period; then further dried naturally or using manure drying machine and bagged in 100kg.
Cost of a bag (100kg) in Ibadan ranges from #300-#400
Cost of a bag (100kg) in North ranges from #3000- #3500
Manure drying machine
The machine dries 85% of the manure and eliminates odours, insects and gases derived from ammonium. Warm stable air from the barn is used for drying. Dust filtration is also involved.
Dr Alaba Bukola
Farmergiant Nigeria Limited.