Toxicity of Mycotoxins (Aflatoxins and Ergots)
Toxicity of Mycotoxins like Aflatoxins and Ergot toxins also very common in livestock animals. Source of toxicity, clinical signs and treatment will be explained in this post.
Aflatoxins
Source
These are produced by Aspergillus spp (A. flavus, A. clavatus and A. parasitcus). The main aflatoxins are named as B1, and B2. The toxins are potent carcinogenic, mutagenic, teratogenic and hepatotoxic.
They produce chronic type of toxicity. Aflatoxin cause hepatotoxicity, nephro-toxicity and immuno-suppression is due to blinding to nuclear DNA and inhibition of RNA formation resulting in the impairment of synthesis of enzymes and essential proteins.
Clinical Signs
Clinical signs of aflatoxicosis include gradual reduction in feed efficiency, milk production, weight gain, anaemia, Jaundice, haemorrhages, uraemia and abortion.
Treatment
There is no specific antidote for the treatment of aflatoxicosis. Symptomatic treatment is given. Supplementation of hepato-protective agents, choline and aftatoxin binders are advocated.
Ergot Toxins
Source
Ergot toxins are produced by the fungi of genus Claviceps pupuria and C. paspali.
The mould contains various alkaloids which are ergotamine, ergonovine, ergocryptine, ergocornine, ergostin and ergosine.
The nervous signs are produced due to interfering with neurotransmitter function of 5-HT, dopamine and norepinephrine in CNS.
Ergot alkaloids cause intense vasoconstriction, damage to capillary endothelium and promotion of thrombus formation leading to stasis of blood supply in the extremities.
Clinical Signs
- Acute: Hyper excitability of nerves i.e. spasms, tremors, incoordination, convulsions and paralysis.
- Chronic: Necrosis, gangrene and sloughing of the extremities (tail, ears, feet or nose), and becoming sensitive to secondary bacterial infections.
Treatment
There is no specific antidote. However Vitamin E and Selenium combined therapy is useful in combating ergot toxin induced gangrene hooves in cattle and buffaloes.
