Comparative Evaluation of Different Techniques for Aflatoxin Detoxification in Poultry Feed and Its Effect on Broiler Performance

Abstract

Aflatoxins (AF), the toxic secondary metabolites produced by Aspergillus flavus and Aspergillus parasiticus, are a major concern in the poultry production. AF metabolites are stable and fairly resistant compounds to degradation (Dalvi, 1986; Park, 2002; Desphande, 2002; Lesson et al., 1995; Feuell, 1996). These metabolites are usually produced during the growth of the Aspergillus flavus, Aspergillus parasitcus and Aspergillus nominus on certain foods and feedstuffs under favourable conditions of moisture, temperature and aeration (Goto et al., 1997; Dutta and Das, 2001). Their toxicity depends on several factors including its concentration, the duration of exposure, the species, sex, age, and health status of animals (Jewers, 1990). Contamination of AF in feed causes aflatoxicosis in poultry that is characterised by reduced feed intake, decreased weight gain, poor feed utilization (Tedesco et al., 2004; Bailey et al., 2006; Shi et al., 2006, 2009), increased susceptibility to environmental and microbial stresses, and increased mortality (Leeson et al., 1995). AF can also cause productive deterioration which is associated with changes in biochemical and hematological parameters (Denli et al., 2004; Basmacioglu et al., 2005; Bintvihok and Kositcharoenkul, 2006), liver and kidney abnormalities, and impaired immunity, which is able to enhance susceptibility to some environmental and infectious agents (Ibrahim et al., 2000; Oguz et al., 2003). AF has been reported to have effect on metabolism in poultry by decreasing the activities of several enzymes that are important in the digestion of starch, proteins, lipids and nucleic acids. Consequently, the activities of serum glutamate pyruvatate transaminase, serum gluatamate oxaloacetate tranferase and γ-glutamyl transferase are increased, primarily indicating hepatic damage (Devegowda and Murthy, 2005). AF is also known to interfere with metabolism of vitamin D, iron and copper and can cause leg weakness (Khajarern and Khajarern, 1999). Severe economic losses have been reported in the poultry industry due to aflatoxicosis (Kubena et al., 1991, 1995). Ultimately, the transmission of AF and its metabolites from feed to animal edible tissues and products, such as liver and eggs, becomes a potential hazard for human health.