Aflatoxicosis in Layer and Breeder Hens

During the past few decades there has been a steady increase in global production of poultry meat and eggs. Although the high nutritive value of eggs and poultry meat has resulted in increasing demand, food quality and safety factors are becoming increasingly significant in determining market value of poultry products. Poultry production is one of the fastest growing sectors of Iranian agriculture. Egg production is increasing at the rate of 4-6 per cent per annum, while broiler production at the rate of 10-12 per cent. At present, Iran is the largest producer of poultry meat in neighboring countries and ninth largest producer in the world, thanks to a 753% growth in meat production from 195 thousand ton in 1978 to 1468 1thousand ton in 2008-09. Broilers are the major source of meat supply in the country. About 270 million broilers are produced every year. Consequent to increased production, per capita consumption /availability has also increased from 7 eggs in 1961 to 42 eggs in 2008. The per capita consumption of poultry meat has increased from 5.4kg in 1978 to 21.8kg in 2008-09. This enormous growth and spurt in poultry production has put a tremendous pressure on proper feeding of poultry in order to sustain the poultry industry in Iran (Manafi, 2010). As mycotoxins are one of the major factors suppressing poultry productivity and also product quality, control of their impact is critical (Oguz, 2011). According to the United Nation’s Food and Agriculture Organization (FAO), approximately 25% of world’s grain supply is contaminated with mycotoxins. The greatest economic impact of mycotoxin contamination is felt by crop and poultry producers, as well as food and feed producers. Contamination of poultry feeds with mycotoxins is one of the major problems associated with the feeding of poultry. Mycotoxins are the toxic metabolites synthesized by a certain naturally growing fungi on animal feed, feed ingredients and other agricultural crops. More than 350 mycotoxins have been identified so far in feedstuffs. Aflatoxin is the most commonly occurring mycotoxin in Iran. Aflatoxins are a group of secondary metabolites produced by a certain species of fungus of the genus Aspergillus (especially A. flavus and A. parasiticus). These fungi are capable of growing and contaminating the grains and cereals at any time before and after the harvest, during storage, transportation and processing of feed ingredients and the formulated feeds after processing. The spores of the fungi remain dormant but when the level of moisture is more than 12 per cent with a temperature of 25-35°C, with humidity of 80 per cent and adequate aeration initiate their growth. Mycotoxins have adverse effect on both health and productivity in almost all species of domestic animals including poultry. In general,