NEGATIVE EFFECT OF MYCOTOXINS IN POULTRY
Compiled & Edited by-DR RAJESH KUMAR SINGH ,JAMSHEDPUR,JHARKHAND, INDIA, 9431309542,rajeshsinghvet@gmail.com
INTRODUCTION:
The word “MYCOTOXIN” is derived from Greek word used for fungus “mykes” and Latin word for “toxicum” which means poison. Mycotoxins are secondary metabolites which are produced by several types of fungi (saprophytic fungi) which grow in different types of feed and foodstuff. Fungi which involved in the production of mycotoxins can be classified into two classes.
v Field fungi: Fusarium species which involve in growth in field.
v Storage fungi: Aspergillus and Penicillium species produce mycotoxin after crop harvesting.
Nearly 10,000 species of fungi are known. Fortunately, most of the species are beneficial for humans and used to produce cheese, bread and antibiotics. Only 50 species are harmful to poultry, in livestock and men they produce toxins which is collectively called “Mycotoxins”. FAO (United Nation’s food and agriculture organization) has estimated that 20-40% food is wasted through mycotoxins every year. Mycotoxins are very common once mycotoxins are produced they cannot destroyed by heating even 3400 C. They cannot be washed off due to low water solubility. They don’t get destruct by even effective chemical treatment. High level of mycotoxins in feed causes acute mycotoxicoses and high mortality rate. Low level of mycotoxin may cause cronic mycotoxicoses with or without clinical symptoms, which decreases production performances and immunosuppressive and presence of residue in poultry meat and eggs. The severity of toxin is depending upon the level of mycotoxin which is ingested and species, age of animal, immune and nutritional status, general health as well as environmental factor.
CLASSIFICATION OF MYCOTOXIN:
1) AFLATOXIN:
Primary Origen: Aspergillus flavis, Aspergillus paracitus, Aspergillus nomus, Aspergillus psedotomarii.
Effect on Poultry:
• Reduce immunity.
• Reduce feed intake and waight gain.
• Reduce feed efficiency.
• Increase mortality.
• It results liver damage, like fatty liver.
• It causes hemorrhages on kidney and intestine.
• It also causes carcinogenesis and teratogenesis.
2) FUMONISIN:
Primary Origin: Fusarium moniliforme, Fusarium verticillioides.
Effect on Poultry:
• Little effect on growth performance at moderate level.
• Reduced immunity and produce growth at high level (200-400 ppm).
3) OCHRATOXIN:
Primary Origin: Aspergillus Ochraceus, Penicillium verrucosum, Penicillium palaitins.
Effect on Poultry:
• Reduce growth performance.
• Reduce hatchability.
• Kidney and liver damage.
• Carcinogenesis and Keratogenesis.
4) TRICOTHESENES:
o Deoxynevalinol.
o T-2 Toxin.
Primary Origin: Fusarium graminearum, Fusarium sporotrichoides.
Effect on Poultry:
• Reduce feed intake and feed efficiency.
• Reduce immunity.
• Decrease egg production.
• Oral lesions and Gizzard erosion.
• Regression of the bursa.
5) ZEARELENONE:
Primary Origin: Fusarium graminearum.
Effect on Poultry:
• Little effect on growth and performance as compared to mammals.
GEOGRAPHICAL OCCURRENCE OF MYCOTOXIN:
MYCOTOXINS AND IMMUNE SYSTEM:
Beside their adverse effect on performance, various types of mycotoxins damage the immune system and increase the susceptibility to diseases. Aflatoxin is more immunosuppressive mycotoxin followed by vomotoxin, T-2toxin, Ochratoxin and fumonisins.
In poultry bursa of fabricius, thymus, spleen and to a lesser extend the cecal toncils and bone marrow constitute the organ contributing to the humoral and cellular immunity. The T-cell which originated in thymus controlled cell mediated immune response. The B-cell which originated in bursa of fabricius and bone marrow control humoral immune response, involving the production of antibodies and immunoglobulins.
Various mycotoxins have adverse effect on immune system by depressing the both cell mediated and humoral immune response.
Ø Effect of Aflatoxin:
It is immunosuppressive and has direct effect on humoral and cell mediate immunity. It results to lowering the defensive mechanism of animal cell mediated response is affected by lower level of aflatoxin and high level of aflatoxin effects the immunoglobulin and antibodies production.
Ø Effect of Ochratoxins:
The immunosuppressive effect of Ochratoxin in poultry results in impairment of both cellular and humoral immunity, and causes atrophy of thymus accompanied by lower circulating immunoglobulins and phygocytes.
Reference-On Request
