Aflatoxins (AF) are a class of mycotoxins
, produced by fungal species of the genus Aspergillus (flavus
) and Penicillium puberulum
, that are often found in the ingredients used to make poultry feed. Foods known to be at a high risk of aflatoxin contamination include corn, cottonseed, peanuts, sorghum, tree nuts, and wheat. There are four main aflatoxins of concern: aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1), and G2 (AFG2); AFB1 is the most common and biologically active.
Crops can become contaminated with aflatoxins while growing in the field, during harvesting, transportation, mixing, or during storage. It grows best at temperatures of 80 to 90°F (26.6 to 32.2°C), and can survive in temperatures as low as 40°F (4.4°C). The mold also requires a high moisture content, and can emerge with 15% moisture content.
Government Regulations for Aflatoxins
The FDA and the EU regulate the amount of aflatoxins present in human food, animal feed, and animal feed ingredients.
- For chick starter and grower feeds, corn, and peanut products, excluding cottonseed meal: Must contain less than 20 ppb
- For laying hen feed and other mature poultry: Must contain less than 100 ppb
- For cottonseed meal intended for all types and ages of poultry: Must contain less than 300 ppb
The adverse effect of aflatoxins depends on the age, species, nutritional status of birds as well as the dose and length of time it was consumed. Aflatoxicosis refers to poisoning from ingestion of aflatoxins in contaminated food or feed. Both acute and chronic aflatoxicosis can occur, however the chronic form is the most prevalent. Chronic aflatoxicosis occurs as a result of prolonged intake of low levels of aflatoxins in the chickens' diet. Resulting adverse affects include:
- Immunosuppression: Increases susceptibility to secondary infection by opportunistic pathogens.
- Reduced vaccine effectiveness: Decreases resistance against viral pathogens, increasing the risk of acquiring the disease they are getting vaccinated against.
- Gastrointestinal tract damage: Causes erosion and roughening of the gizzard lining, resulting in decreased absorption of nutrients, stunted growth, nutrient-deficient related syndromes, and lowered feed conversion.
- Liver damage: The primary site of toxicity due to aflatoxins is the liver. Exposure causes hepatic lesions and enlargement of the liver as well as fatty liver.
- Production losses: Decreases egg production and egg quality in laying hens and hatchable eggs in breeding chickens.
|Allium spp (Garlic) extract||El-Barbary MI 2016|
|Bacillus subtilis||Zhang L et al., 2016; Jia R et al., 2016; Fan Y et al., 2015; Fan Y et al., 2013|
|Beer fermentation residue (BFR)||Bovo et al., 2015|
|Bentonite clay||Dos Anjos, F. R., et al, 2015; Fowler, J., Li, W., & Bailey, C. (2015)|
|Berevibacillus laterosporus||Bagherzadeh K et al., 2012|
|Cactus cladode extract (CCE)||Brahmi D et al., 2011|
|Cellulosimicrobium funkei||Liu J et al., 2016; Sun LH et al., 2015|
|Citrus fruit oil||Kumar DS et al., 2015|
|Curcuma longa (Tumeric) extract||Dos Anjos, F. R., et al, 2015|
|Hydrated sodium calcium aluminosilcate||Chen, X., Horn, N., & Applegate, T. J. (2014)|
|Lactobacillus||Monson MS et al., 2015; Rawal S et al., 2014|
|Natural honey||Yaman T et al., 2016|
|Neutral electrolyzed oxidizing water (NEW)||Jardon-Xicotencatl S et al., 2015|
|Nigella sativa (Black cumin)||Khan SH et al., 2013; Aydin R et al., 2008|
|Resveratrol||Sridhar M et al., 2015|
|Rosmarinus officinalis||Manafi et al., 2014|
|Saccharomyces cerevisiae (Yeast Extract)||Abadeen, Zain Ul, et al.|
|Selenium||Chen et al., 2014|
|Silybum marianum (milk thistle) seeds||Malekinejad, Pouyan, et al. (2015)|