Mycotoxins in Poultry

Mycotoxins are the secondary metabolite produced by fungal species in feed under stressful production conditions-are considered to be among the most important feed-born stress factors to impact birds. They produces a variety of diseases, collectively called ‘mycotoxicosis” directly or in combination with other primary stressors such as pathogens

Fungal Species	Toxins Produced
Aspergillus flavus	Aflatoxins B1,B2, cyclopiazonic acid
Aspergillus parasiticus	Aflatoxin B1, B2, G1, G2
Aspergillus ochraceus	Ochratoxin A
Aspergillus versicolor	Sterigmatocystin, cyclopiazonic acid
Penicillium verrucosum	Ochratoxin A citrinin
Penicillium roqueforti	Roquefortine, penicillic acid
Penicillium purpurogenum	Rubratoxins
Penicillium expansum	Patulin, Citrinin
Fusarium sporotrichiodes	T-2 toxin
Fusarium verticillioides	Fumonisin B1
Fusarium graminearum	Eoxynivalenol, Zearalenone
Alternia alternate	Tenuazonic acid
Stachybotrys atra	Satratoxins

Effects of Mycotoxins

Aflatoxins B1 (AFB1) 

• Primary hepatotoxic and secondarily nephrotoxic
• Immunosuppression
• Poor immune response of vaccines
• Drop in egg production and poor hatchability
• Bile duct epithelium hyperplasia
• Degenerative and necrotic changes in hepatocytes

Ochratoxicosis (Ochratoxin)

• Nephrotoxic
• Anaemia, decreased skeletal integrity
• Impaired coagulation of blood, impaired phagocytosis and reduced growth rate

Citrinin toxicosis (Citrinin)

• Endemic nephropathy
• Embryotoxic 
• Immunotoxic mycotoxin
• Neurotoxic and teratogenic
• Enlargement in size and the weight of the liver 

Trichothecenes toxicosis (T-2 toxin)

• Buccal-oral ulceration/necrosis 

Moniliformin toxicosis

• Sever cardiotoxicity in chicks
• Damaging effects on the liver and kidneys

Fumonisins toxicosis (FB1-Fumonisin B1)

• Multifocal hepatic necrosis 
• Hepatocellular and biliary hyperplasia 

Source, effect & toxic level of Mycotoxins

Feed ingredients	Mycotoxin	Origin	Attention Limit	Toxic Limit
Maize, Oats	Aflatoxin	Aspergillus flavus Aspergillus paraciticus Aspergillus nomius	50 ppb	1000 ppb
Wheat, Corn, Barley	Trichothecenes -Deoxynivalenol (DON) T2 Toxin	Fusarium graminearum Fusarium sporotrichoides	400 ppb 1000 ppb	T2, DAS : 2000 ppb DON: 10000 ppb
Maize, Oats, Wheat, Barley, Oats	Ochratoxin A	Aspergillus ochraceus Penicillium verrucosum	100 ppb	2000 ppb
Maize	Fumosin	Fusarium moniliforme Fusarium verticillioides	10000 ppb	50000 ppb
Maize, Barley	Zearalenone	Fusarium graminearum	2000 ppb	100000 ppb

The problem of mycotoxicosis is not so easy to solve and requires constant attention throughout the entire process of grain harvest, shipping, storage, feed manufacturing, and its formulation. Utilization of mycotoxin contaminated raw materials presents a major problem. Detoxification as well as routine mycotoxin analysis of feed ingredients is an important step in a control programme at field level. Physical, chemical and biological methods are essential to counteract the level of contamination of mycotoxins in foods and feeds. The cost involved and reduction in nutritive value of feed are some of the constraints which limit the use of such procedures during the feed formulation.

Various studies further suggest that the total elimination of moulds and their toxins is practically impossible, so there is a great need for the use of such agents that are able to bind the toxins selectively in the gut, thus limiting their bioavailability in the consumers. In addition, the possible presence of toxic residues in the poultry products (egg, meat), which enters into the food chain may have potential risk by their detrimental effects on human health. At present, no limits have been set in India for most of the mycotoxins known to produce adverse effects in poultry birds. There is an urgent need to set a rational limit for such mycotoxins for the economic growth of poultry industry.

The most important mycotoxin risk is invisible 

Acute mycotoxicosis clinical symptoms: 

• Low feed intake and vomiting 
• Dermal lesions 
• Liver & kidney damage 
• Reproduction troubles 
• Mortality 

Majority of cases subacute mycotoxicosis: 

• Poor performance  
• Immunity 
• Digestive troubles 
• Feed conversion ratio 

So due to mycotoxicosis there is reduction in villi size and inhibition of nutrients transporters resulting lower Nutrient absorption. Due to gut barrier damage there is alteration of tight junctions, decrease goblet cells functionality. Also impairment in Immune functions either Innate or acquired immunity so birds are more prone to various diseases and also poor vaccination response.

Prevention & control of Mycotoxicosis:

In addition to preventative measures, by using the right mycotoxin adsorbent we can protect our business and animals from the negative effects of mycotoxins. As this approach is rather inexpensive and products can be easily incorporated in the birds diet the use of mycotoxin binder has become common practice.

The guidelines for selecting a good mycotoxin binder to comply with specific criteria include: 

Proven binding efficacy

Reduction of the potential for hazardous mycotoxins within the gastro-intestinal tract

Broad and specific spectrum of activity: binding wide range of mycotoxins& not bind with nutrients

Absence of nutritional side effects

Not containing any toxic substances