This is recognized as a high crude protein source with an imbalanced, relatively poor amino acid profile. Handling and processing of blood is difficult in low-technology situations. For processing small amounts, one method is to absorb the blood on a vegetable carrier such as citrus meal, brewers grain, palm kernel, ground maize, cob rice or wheat bran, after which the material is spread out for drying on trays heated from below or placed in the sun (Sonaiya, 1989). At the farm level, the blood may be supplied from the slaughter of livestock. Abattoirs and slaughterhouses provide large volumes of blood for making up feeds at the commercial level.
Farina, et al., (1991) described a technique used to collect termites for scavenging poultry. Briefly, the straw of sorghum, millet and maize are chopped, placed in clay pots or calabashes and moistened. The mouth of the container is placed over a hole in a termite colony under Small-scale poultry production 21 construction. The container is covered with a jute sack to prevent drying out and a heavy stone is placed on it to secure it in position. After three to four weeks, a new colony of termites should be established inside the container. The eggs and larvae are particularly relished by chicks, guinea keets and ducklings, while adult birds also feed on the adult insects. Cattle dung can be used in place of the cereal straw.
Alao and Sonaiya (1991) grew maggots on cowpea testa (seed coats) and monitored the chemical composition of the mixture over ten days. Cowpea testa samples were placed in a basket near a pit latrine to attract flies to lay eggs on them. Every two days, a sample was steeped in boiling water to kill the maggots. They were then sun-dried and ground before analysis. Results showed that the Crude Protein content of the mixture doubled by the second day. Soukossi (1992) produced maggots from fibrous vegetable material and poultry droppings. The method was developed for feeding fish, but can easily be adapted for smallholder poultry. A tank with a capacity of one cubic metre is filled with water to about 15 cm from the top. Dried stalks of maize, amaranth, groundnut, soya and other legumes are soaked in the water to which some poultry droppings are added. Flies and other insects are attracted to the soaked material to lay their eggs. After five to seven days, eggs are hatched and larvae are sufficiently developed to be fed to fish. Beyond this period the maggots develop into adult flies. It was observed that up to 50 percent of the eggs laid by flies died if exposed to the sun for several hours. A cover, at least for the hottest hours of the day, is therefore necessary. Similar trials have been carried out in Burkina Faso.
Vorster et al. (1992) produced earthworms as a source of protein for chicken feed. In an area of 25 m2 , one kg of fresh earthworm biomass was produced daily. This is sufficient to supplement at least 50 chickens with high-quality protein. It must be noted, however, that earthworms (and snails as well) may be important vectors for tapeworms such as Davainea and Raillietina and also contain a growth inhibitor.
Other animal products
Aquatic animal products containing mineral sources include marine shells from mangrove oysters (Ostrea tulipa), mangrove periwinkles (Tympanostomus fuscatus) and clams, and shells from land snails. Marine shells are abundantly available in coastal areas. Snails and their shells are harvested from forests, but there is also on-going development of productive snail farms. It is estimated that a box with a capacity of one cubic metre capacity on a snail farm can yield 40 snails each year. Ducks are an important biological control of the semi-aquatic golden snail in the Philippines and Bangladesh. Other marine by-products, such as prawn dust and shrimp heads, supply both minerals and protein.
There are feed resources available for feeding poultry at all levels of production. Smallholders using the semi-intensive system who make their own feed must base the rations on homeproduced feed resources or obtain the ingredients locally. In backyard systems, available resources should be supplemented with appropriate nutrients as necessary. Food products from household waste fed to free-range birds should also be supplemented. Potential substitutes for expensive commercial feeds are cassava, sweet potato, coco yam (Colocasia esculenta), arrowroot (Marantha arundinacea), coconut residues, coconut oil, palm oil and other nontraditional energy sources. Non-conventional feedstuffs which are good substitutes for fish meal and soybean and groundnut oil meals include earthworm meal, maggot meal, winged bean, pigeon pea, jack bean, Azolla (A. pinnata, A. caroliniana, A. microphylla), leaf meals and leaf protein concentrates. In different regions, the importance of these feed resources for family poultry depends on their availability in sufficient quantities for farm use, simple preparation and processing methods, knowledge of the potential nutritive values and (for comparison) the price and availability of conventional commercial feeds. For the family poultry situation with a scavenger flock, free-choice supplements with three containers each containing either protein-rich, energy-rich or mineral-rich feed sources will provide a solution to the problem of balancing nutrient intake for different age-groups. Poultry have an instinctual ability to select exactly what they need in the above food nutrient groups, and will not overeat from any one container. Young growing poultry (under two months of age) should always be fed in a “creep” system, where older stock cannot get access to their feed supply.