Quails have been farmed since ancient times. The earliest known representation of the quail can be found in the Egyptian hieroglyphics (2000 B.C), where the quail represents the letter “W” in the alphabet (Shanaway, 1994).
The Japanese quail, Coturnix Coturnix japonica is known to have been domesticated since the 12th century in Japan, mainly for its ability to sing. Intensive production of the species started in Japan in the 1920. Then the first egg lines were developed by selection. They were successfully introduced from Japan to America, Europe and Middle East between the 1930 and 1950, where specific lines were bred for egg and meat production (Ashok and Prabakaran, 2012).
Chickens and turkeys are the most common sources of poultry meat (87% and 6.7% of total poultry production, respectively). However, other commercially available poultry meats include meat from ducks (4% of total poultry production) and from geese, pigeons, quails, pheasants, ostriches and emus (combined about 2.3% of total poultry production). Chicken accounts for about 86% of all poultry raised worldwide. In the European Union (EU), chicken meat accounted for only 79% of all poultry meat produced in 2007, while turkey, duck, pigeon, geese and quail meat accounted for 15% (FAO, 2009).
The Worlds’ egg production is dominated by domestic chickens. The (FAO, 2010) estimated that chickens, turkeys and ducks produced 87%, 6.7% and 4% of total poultry eggs worldwide respectively. The others, that is, geese, pigeons, quails, pheasants, ostriches and emus all combined produce about 2.3% of total egg production (Arthur, 2013).
The Economic Commission for Africa reported in their online reports stated that there is a high demand for animal protein in Africa but animal production falls short of this demand (Dudusola, 2013).
One way of increasing protein supply will however be to diversify poultry production to include species with short generation intervals such as quails (Kayang et al., 2004). Quails are generally kept for egg production in Far East and Asian Countries, while they are reared primarily for meat production in European and American Countries (Minvielle, 2004).
Japanese quail (Coturnix coturnix japonica) is becoming more popular as a source of meat and eggs in various parts of the world including Egypt. Quail have also assumed worldwide importance as laboratory animals (Baumgartner, 1994).
Quail meat and egg is a very good source of animal protein that is very low in fat and cholesterol which makes it the choice of people suffering from high blood pressure (Rogerio, 2009).
Quails have less feed requirement of about 20 - 25 g feed per day compared to chicken that requires 120 – 130 g per day (Ani et al., 2009). Japanese quail are marketed at 5 – 6 weeks of age for meat with a body weight of 200 – 240 g. The female quails come into lay in about 6-7 weeks of age, reared for breeding up to 10-12 months of age and produce about 250-270 eggs, each weighing 12-13g (Gandhimathi et al., 2014).
In spite of its small size, Quail eggs are packed with vitamins and minerals even with their small size, their nutritional value is three to four times greater than chicken eggs. Regular consumption of quail eggs helps fight against many diseases which are a natural combatant against digestive tract disorders such as stomach ulcers, strengthen the immune system, promote memory health, increase brain activity and stabilize the nervous system. They help with anemia by increasing the level of hemoglobin in the body while removing toxins and heavy metals (Troutman, 2012).
Fertility and hatchability rate of all eggs set or fertile eggs, and embryonic mortality rate in poultry are influenced by many factors including male/female ratio, genetic, age of parents, nutrition, storage conditions and period of eggs, quality and weight of eggs, and incubation conditions (Altan et al., 2002). Temperature is the most important factor affecting embryonic development, hatchability and post hatch performance. Optimum incubation temperature is normally defined as that required to achieve maximum hatchability (Romao et al., 2009).
The performance of artificial incubation in poultry species, including Japanese quails, can be affected by a series of factors, such as egg turning (Moraes et al., 2008), egg storage (Moraes et al., 2009).