Determining the best response level of performance parameters in broilers fed with different levels of aflatoxins and amino acids

Abstract

Introduction: Food or feed contamination with aflatoxin B1, which is a secondary and
toxic metabolite of Aspergillus flavus and Aspergillus parasiticus, is a major problem
in most parts of the world, especially in developing countries. Harmful consequences
of the presence of aflatoxins in food encouraged the researchers to find the safe,
effective and efficient procedures to control this toxin prior to entering the human food
chains. The aim of this study was to investigate the effects of the amino acids glycine,
glutamic acid and N-acetylcysteine on the growth performance of broilers under
aflatoxicosis, and to determine optimum level of these amino acids.
Materials & Methods: 690 Ross 308 broilers in 17 experimental groups were fed
with feeding 5 different levels of amino acids of glycine, glutamic acid, Nacetylcysteine
and Aflatoxin with 4 replications and each replication included 10
chickens. Performance traits including feed intake, body weight gain and feed
conversion ratio were measured weekly from one to 21 days of age. The results of
performance traits were analyzed using the Response Surface Methodology (RSM)
model and the central composite design.
Results: The results of the central composite design were more consistent and
significant in broiler chickens with the quadratic regression model which had the
highest values of R2. The results of the present study showed the negative effects of
aflatoxin on feed intake and body weight gain, which in turn increased the feed
conversion ratio. The results also showed that supplementation of glycine, glutamic
acid, N-acetylcysteine amino acids to the diet moderated the negative effects of
aflatoxin B1.
Conclusion: Dietary supplementation with three amino acids glycine, glutamic acid
and N-acetylcysteine as the main precursors of glutathione can reduce the negative
effects of aflatoxin on the performance parameters of broilers by improving the
antioxidant system. Also, using the response level methodology by providing
appropriate statistical and graphical information has a high ability to identify the
superior model and determine the optimal level of these amino acids in the diet
contaminated with aflatoxin.