ARTICLE BY S.K.MAINI
Emu's like all other animals and birds are prone to damage by the mycotoxins. Various types of fungi are known to grow in the agricultural fields, on the plants, on grains, in the grain processing and storage areas in the feed processing andmanufaturing plants and during their handling and trasportation, these fungi produce several types of mycotoxins simultaneously, these work tobether causing damage to all species of animals and birds.
The mycotoxin producing fungi fall generally into two different groups: those that inavade the plants on the field before harvest the field fungi, and those that ocur after harvest - the storage fungi, and nothing is ever done to control fungi at these levels. Very few of the several thousand species of fungi are known to prduce mycotoxins,approximately 95 of the mycotoxins existing in the feed industry are already prduced by the time ingredients reach the feed plants or the end users.
History of Mycotoxins
Stevens et al. 1960: reported it as turkey X disease, Abrams 1965 reported ducklings to be most susceptible, Asao et al. 1963 isolated it and studied its chemical structure , lot of work has been done on aflatosins till date in laboratoreis around the world, work on other mycotoxins is either imcomplete or still being done.
Classification of Mycotoxins
Mycotoxins are classified according to the system they affect in the body of the animal or the bird.
Hepatotoxins
This group of mycotoxins damage the liver and its function, most important in this group is aflatoxins, the otheres are Rubratoxins Luteoskyrin, Sporidesin etc.
Nephrotoxins
Mycotoxins of this group damage the kidneys and their function Ochratoxins and Citrinin are the main toxins in this group.
Neurotoxins
This group of mycotoxins target the nervous tissues causing incoordination, starvation and deaths. Patulin, Pentitrema and Citreoviridin belong to this group.
Cytotoxins
This group causes damage at the cellular level, interfere in metabolic activity leading to general debility, incoordiation, starvation and death. T2 toxin, Trichothecenes, Don, Vomitoxin, Fusarenon etc fall in this category.
Estrogenics
Zearalenone belongs to this group, it interferes in the hormones functions and distrubs the metabolic activity.
Misc - Mycotoxins
Ergot and Lupinosis fall into this category, they interfere in metabolism and cause damage.
Variety of Mycotoxins are produced by strains of Aspergillus falvus and most strains of A. parasiticus, when they get optimum conditions to grow and produce the mycotoxins, like the availability of food, air, temperature and humidity.
What you will notice in the Emu's
Sudden onset
Inappetence-off feed
Defected appearance - reluctant to move
Ataxia leading to paralysis
Sitting unable to stand and walk
starvationand dehydration leading to death.
The above mentioned points will be seen as a result of toxins affecting the liver, kidneys, nervous system, neuromuscular system, damage to gastro intestinal tract, altered blood parameters, malabsorption of nutrients, increased susceptibility to infections etc.
If the toxins are in smaller quantities and not enough to kill the Emu's then you will notice.
poor growth, No increase in body weight with age, Stunted growth, Hunch backs , Lameness and leg bends, Loose motions, Poorer FCR's , Depressed appetitie,Sensitivity to temperature extremes , Bruising and injuries, Reproductive problems like infertility etc.
Mycotoxins affect regardless of age, sex, stage of production, systems of management , species etc.
Young animals and birds are more prone to mycotoxins damage than the adults, groweres and adults on vegitables and greens suffer less than those only on formulated feeds. Mycotoxin preventers are easier to add in feed given to chicks, growers and adults that are on mash type feeding as compared to those on pellets.
Strategies to prevent, reduce and treat mycotoxins
Withdraw and remove the feed that caused damage , chang eand use new dfeed with the followeing additions.
Prevent Molds in feed ingredients to avoid toxins.
If new grains are beign used or during periods of high humidty add mold inhibitors to retard and control mold growth, sun dry the ingredients before adding mold inhibitors, the feed storage area be well ventilated, feed bags be placed on pallets for better aeraction
Use additives to reduce the effect of mycotoxins
A variety of toxin destroyers, neutralizers, binders and reducers are available in the market. Addition of a good toxin destroyer is preferred.
Liver and Kidney supportive's will help
Products that ensure proper functioning of the liver, its repair and maintenance will help birds recover faster, toxic metabolites whould be throown out of the system quickly to minimize the damage they do, products that improve the filtration process to eliminate the toxic metabolites are recommended.
When effected by mycotoxins the requirements of trce minerals and vitamins increase, these have to be given extra for few weeks either through drinking water or through feed if the birds are still eating.
