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Poultry plays a significant role in the livelihood of both rural and urban population
of Ethiopia. The total chicken population in the country is estimated to be 42.9 million
(CSA, 2005). About 99% of these are raised under free ranging or traditional system, and
the majority of the feed is obtained through scavenging, Scavenging Feed Resource Base (SFRB). The SFRB includes: the household cooking waste, cereal and cereal byproducts, roots
and tubers, oilseeds, trees, shrubs (including Leucaena, Calliandra and Sasbenia) and fruits,
animal proteins, aquatic plants (Lemna, Azolla and Ipomoea aquatica), and commercially
prepared feed, etc. The amount and availability per bird of SFRB are significantly dependent
on season, grain availability in the household, the time of the grain sowing and harvest, and
the biomass of the village stock (Tadelle, 2004).
Maize is well accepted as the king of feed ingredients. It is a primary source of energy
supplement and can contribute up to 30% protein, 60% energy and 90% starch in an
animal’s diet (Dado, 1999). 70-80% of maize production is used as a feed ingredient in
the world. In most countries, maize constitutes the bases of poultry feeding. It contains
little cellulose and a relatively high proportion of fats, which classes it among the best energy
sources. However, it contains few nitro-compounds. Its utilization is limited only by the
need to maintain the energy/protein balance, and utilization rates are commonly between
45 and 50% at center level.
Stating the content of the most important amino acids indicates the quality of proteins,
in particular feed ingredient. Of the essential amino acids in poultry rations, methionine, lysine,
arginine, glycine, and tryptophane are referred to as critical Amino Acids (AAs), since these
are usually deficient in ordinary practical poultry rations. This is because cereal grains, like
maize, are usually low in critical amino acids, which make up a large proportion of poultry
ration. It is thus essential to include good proportion of animal protein sources such as fish
meal, meat meal and blood meals or synthetic amino acids to ensure optimum performance.
Hence, protein content as a measure of nutritional value of feed is becoming less important,
and each amino acid is being considered individually. Unfortunately, quality protein sources
are very expensive and not easily available at the local market, and the use of animal origin
protein sources is banned by the government of Ethiopia.
As a result of several decades of research, particularly at CIMMAT in Mexico and Ghana,
maize germplasm is available that has protein quality plus a grain yield potential and
comparable to those of normal maize. The outcome of this research is called Quality Protein
Maize (QPM).
Although Normal Maize (NM) contains between 8 and 9% protein, the quantity of two
essential amino acids, lysine and tryptophan, is below nutritional requirements for monogastric
animals. Therefore, utilization of QPM can correct this deficiency and may be advantageous
in the diets of livestock and monogastric animals in particular.
QPM contains an improved amino acid balance: 56% more lysine and 66% more
tryptophan than other varieties of maize. It can reduce the need for high quality proteins
in poultry diets and reduce feed cost. Such varieties have been evaluated elsewhere using
poultry, particularly broilers. No such comparative trial has been carried out to establish its
usefulness in our country.
BH.QP542 is one of the various varieties of QPM introduced by one of the regional
research institutes, Adet research center, to the farmers found in the region, and it has become
one of the most accepted maize varieties. Therefore, the major objectives of this study were
to determine the optimum level of inclusion of QPM in Rhode Island Red (RIR) starter and
grower ration and evaluate the growth rate and feed efficiency of these classes of chicken.
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