Toxicity of Zearalenone in Poultry

 Zearalenone is the most common prevalent mycotoxin found in feed and raw materials available in South Asian Region. Zearalenone (ZEN) at lower concentration highly impacts the Swine. However, ZEN at higher concentration or presence of more than one mycotoxin will have a great impact in poultry especially Breeders and Layers.

Zearalenone Toxicology

Grains infected with the fungus Fusarium graminearum and Fusarium. roseum are the source of zearalenone, a mycotoxin with estrogenic activity. Zearalenone occurs in corn, sorghum, wheat, barley, oats, milo, rye, and other grains. Toxicity occurs chiefly in swine as reproductive failure. Chickens tolerate Zearalenone better than swine but it has potential adverse effects in bird performance and egg yield and may be an indicator of other potentially toxins present in the sample.

Tolerance limit

Zearalenone at more than 0.5 ppm (500 ppb) is detrimental to broiler breeders and layer that experienced a reduction in egg production. The birds had lowered serum progesterone, ascites, and cystic inflammation of the oviduct.

How Zearalenone affects the reproductive system?

Zearalenone mycotoxicosis in broiler and leghorn chickens affects the reproductive tract and sex hormone-sensitive receptors. ZEN interacts with both types of Oestrogen receptors and also a substrate for hydroxysteroid dehydrogenases, which convert ZEN into two stereoisomeric metabolites, α-zearalenol and β-zearalenol. Alpha-hydroxylation results in an increase of oestrogenic potency as compared to the parent compound. ZEN is grouped with the compounds known collectively as endocrine disrupters

How it impacts the breeder chicken?

In Poultry Layers and Breeder it impacts,

•  Egg specific gravity
•  Eggshell thickness
•  Interior egg quality
•  Decrease in Serum calcium and increase of phosphorus content
•  Reduced feed intake and egg production
•  Inflammation of Bursa of Fabricius
•  Hormone-induced cloacal swelling
•  Cysts developed on the peritoneal surface and within the oviduct.
•  Decreased comb and testes weight
•  Oviduct enlargement and
•  Leukopenia (decrease in the number of White Blood Cells)

Presence of ZEA in poultry feed and raw materials: -

Customer Laboratory Services (CLS) of Kemin regularly monitoring the prevalence of mycotoxin in South Asian feed and feed raw materials.

•  Out of 61 samples was analyzed in March, 42 samples were positive to ZEA (69%)
•  In the positive samples, 43% samples were shown toxicity at higher than tolerance limit

Graph1: % of ZEN positive samples                                             Graph 2: % of samples above tolerance limit

Control of Zearalenone mycotoxin: -

To control the impact of ZEN mycotoxin - a good quality, non digestible, broad spectrum mycotoxin binder which is highly specific to mycotoxins binding without impacting the nutrients present in the feed. There are several binders available in the market which has got the claim against ZEN mycotoxin but not proven in in vitro or in vivo studies. Inclusion of good quality mycotoxin binder from KAI like Toxfin - which is proven in in vivo and in vitro efficacy against 7 major prevalent mycotoxins will give complete protection to the Poultry bird.

References: -

• v Effect of zearalenone on female White Leghorn chickens. Appl Environ Microbiol39: 1026-1030.
• v Faculty of Veterinary Science, Budapest, Hungary - Szent Istvan University
• v Effect of addition of a detoxifying agent to laying hen diets containing uncontaminated or Fusarium toxin contaminated maize on performance of hens and on carryover of zearalenone. Poult Sci 81:1671-1680
• v Metabolism of [14C] zearalenone in laying hens. J Agrlc Food chem 28:286-291.
• v Effect offeeding Fusarium roseum f. sp. graminearium contaminated corn and the mycotoxin F2 on the growing chick and laying hen. Poult Sci 50:627633.