MYCOTOXINS:

EFFECTS ON DAIRY PRODUCTION

Introduction:

Mycotoxins are biologically diverse toxic secondary metabolites of fungi and are being

produced by several mould species including Aspergillus, Fusarium and Penicillium. The

occurrence of mould and mycotoxins in food and animal feed is a problem of major concern

internationally. Several hundred mycotoxins have been identified and reported in scientific

literature yet but few of them pose a sever threat to public health and animal agriculture

industry. Various agriculture commodities can be contaminated by moulds and mycotoxins

during yield (growth and maturation), harvesting, transportation, storage and feed processing

and their adverse effects are manifold. According to Food and Agriculture Organization (FAO)

more than 25% of the world grain supply is being affected by mycotoxins annually. They have

great economic impact on agriculture and livestock producers and food and feed processors.

The worldwide economic losses due to mycotoxins have been found to be more than several

hundred million US dollars per annum and their control is critical.

Ruminant species are generally thought to be less sensitive to mycotoxicosis as compared to

other food producing animals. Ruminant diets generally include both forages and concentrate

which may increase the risk of mycotoxins in comparison with animals that do not consume

forages. Millions of tones of forage is being produced by livestock producers and consumed by

animals annually and interestingly majority of it is contaminated with fungal species invading

forage plants prior to harvest or during storage as hay, straw or silage. Preserved forages like

silage are more prone to be contaminated by moulds and their associated mycotoxins than dry

forages if anaerobic conditions are not maintained properly. Moreover, the green fodder

cannot be considered completely safe from mycotoxin contamination because they are equally

prone to be contaminated by fungal endophytes that produce toxins.

Effects of Mycotoxins:

The negative effects of mycotoxins on human and animal health has been recognized and

reported by scientific community. During World War II a large group of Russian soldiers was

found to be affected by a sudden disease showing severe dermal necrosis, hemorrhages and

bone marrow destruction and clinical investigations revealed that these soldiers were fed to

grains which were contaminated with some species of fungi belong to genus Fusarium. In early

1960s the entire turkey population of Britain was affected by a fetal liver disease known as

Turkey X Disease and it was attributed to the feeding of contaminated peanut meal imported

from Brazil. This incidence was known to be the major breakthrough in the initiation of studies

on mycotoxins referred to as mycotoxicology. The economic impacts of mycotoxins include loss

of human and animal life, increased health care and veterinary care costs, reduced livestock

production, disposal of contaminated food and feed and investment in research and

applications to reduce severity of mycotoxin problem. Intake of mycotoxins at larger doses can

primarily cause acute health and production problems in dairy herds. Generally in field

conditions the chronic effects of mycotoxicosis are manifold which include higher incidence of

infectious diseases, poor reproductive efficiency and suboptimal milk and meat production.

Ruminant have a complex and diversified gastric system and rumen contains a dense and

diversified microbial ecosystem (bacteria 1011/ml, protozoa 106/ml and fungi 104 zoospores/ml).

This complex micro biota of rumen helps ruminants to degrade certain mycotoxins and protect

them from acute toxic effects of these mycotoxins. However, rumen metabolites of the parent

mycotoxin may be equally or more toxic and also contribute to chronic clinical manifestations

due to long term consumption of mycotoxins at very low levels. In general mycotoxins pose

their negative effects in dairy animals by following means:

1. Poor feed intake or feed refusal

2. Reduced nutrient absorption and impaired metabolism

3. Imbalance in the hormonal physiology

4. Immunosuppression and high incidence of infectious diseases

5. Imbalance of the microbial ecosystem of rumen

Impact of mycotoxins in dairy animals is diversified in nature and in field conditions it becomes

very difficult to recognize the negative impact of mycotoxins in productive and reproductive

efficiency of farm animals. The clinical signs and symptoms of mycotoxicosis in farm animals are

often non specific and confusing and due to the onset of opportunistic diseases the clinical

diagnosis becomes very difficult or sometimes impossible. In general the clinical symptoms

include suboptimal production, reduced feed intake, intermittent diarrhea, rough hair coat,

reduced reproductive efficiency, irregular estrous cycles, early embryonic death and decreased

conception rates. Immunosuppression is a major consequence of chronic mycotoxicosis in farm

animals which results in increased susceptibility to infectious diseases and failure of vaccination

and drug therapy.

Important Mycotoxins for Dairy:

Forages and concentrate can be contaminated with many species of fungi including Aspergillus,

Fusarium and Penicillium. The major mycotoxins for dairy cattle include Aflatoxins, Ochratoxins,

Trichothecenes (T2 and DON) and Zearalenone.

Aflatoxins:

Aflatoxins are primarily produced by Aspergillus flavus and Aspergillus parasiticus and are highly

toxic, mutagenic and carcinogenic compounds. Major forms of aflatoxins include B1, B2, G1 and

G2 but Aflatoxin B1 is the most widespread and biologically active form. Because of its

carcinogenic potential Aflatoxin B1 has been extensively studied throughout the world.

Aflatoxin B1 is generally metabolized into Aflatoxicol and Aflatoxin M1 in rumen and it is

secreted in the milk in the form of Aflatoxin M1. According to the limits of FDA the level of AFB1

should be less than 20 ppb in the feed of lactating cows and 0.5 ppb in milk. Although no level

of aflatoxin can be considered safe for farm animals, the degree of toxicity is related to toxin

level, duration of feeding and intensity of other stresses affecting the animals. Symptoms of

acute aflatoxicosis include loss of appetite, ataxia, lethargy, rough hair coat and enlarged pale

fatty liver. In chronic cases of aflatoxicosis reduced feed efficiency and milk production is

evident with reduced resistance to infectious diseases and poor response to vaccination and

drug therapy.

Ochratoxins:

Ochratoxin is primarily produced by Aspergillus ochraceus and Penicillium verrocosum and

occur in wide variety of feedstuffs. Ochratoxin A has been reported to affect dairy cattle but at

very high levels as it is rapidly metabolized in the rumen. Young calves are more sensitive to

Ochratoxin A toxicity with prolonged exposure. In mature animals the primary toxic effect is the

alteration in protein synthesis and few signs of hepatic toxicity. Feeding of mouldy hay with

high levels of Ochratoxin A may results in abortion and death of dairy cattle.

Trichothecenes (T2 and DON):

Trichothecenes are generally produced by several species of Fusarium and main trichothecenes

encountered in ruminant feeds belong to group A (T2 toxin) or group B (DON or Vomitoxin). T2

toxin has been associated with gastroenteritis, intestinal hemorrhages and death. Field

observations suggest that T2 toxin is a severe gastrointestinal irritant which can cause

hemorrhages and necrosis of intestinal tract. Exposure of dairy cattle to T2 toxin may cause

bloody diarrhea, decreased feed intake, poor milk production and absence of estrous cycles. T2

induced immunosuppression in dairy cows is mainly due to alteration in the protein synthesis.

DON is commonly referred to as Vomitoxin. In cattle DON has been associated with reduced

feed intake and lowered milk production. The trichothecenes are generally immunosuppressive

and may be more toxic in animals with low levels of immunity.

Zearalenone:

Zearalenone is primarily produced by Fusarium graminearum and several other species of

Fusarium. Zearalenone is a natural contaminant of corn and wheat but it may also be present in

other feedstuffs. Zearalenone has a close similarity with estrogen regarding its chemical

structure and may cause estrogenic effect in animals. Zearalenone is degraded by rumen

microbes to alpha-zearalenol which has been considered four times more estrogenic than

parent toxin. The primary effects of Zearalenone are reproductive problems which include

decrease in embryo survival, edema and hypertrophy of genitalia in pre-pubertal females,

decrease in amount of luteinizing hormone (LH) and progesterone produced affecting the

morphology of uterine tissues, feminization of young males due to decreased testosterone

production and infertility. Other clinical manifestations include vaginitis, vaginal secretions,

abortions, infertility and mammary gland enlargement of virgin heifers.

Prevention and Control of Mycotoxins:

Mycotoxins are quiet diversified molecules and are produced by various fungi at certain stages

of their life cycle. In a feedstuff if a particular mould is visibly present it does not indicate the

presence of typical mycotoxin and in contrast if a feedstuff is visibly free from any mould it does

not indicate that mycotoxins are absolutely absent. Moreover the mycotoxins are quiet

resistant molecules and do not respond to any thermal or chemical treatment which is capable

of destroying certain moulds. So in practical field conditions the control of mycotoxins is very

critical and should be accomplished in two stages. First stage is the elimination of visible moulds

growth in a particular feedstuff and second stage is the detoxification of that feedstuff form any

existing mycotoxin. Various strategies are being used in field for the prevention and control of

adverse effects of mycotoxins which include chemical detoxification, nutritional strategies,

application of mineral clays and use of yeast cell wall based adsorbents in feedstuffs and

compound feeds. The most effective and practical method for the deactivation of mycotoxins

so far is the use the inert adsorbents in diets of animals to stop the absorption of mycotoxins

from the intestine. An ideal toxin binder should have some properties which are as follows:

1. Ability to bind to a broad spectrum of mycotoxins

2. Ability to mix uniformly in the finished feed

3. Ability to show effectiveness at very low inclusion rates

4. Ability to tolerate high temperature during pelleting process

5. Ability to remain stable at a wide range of pH in gastrointestinal tract

6. Ability to show no affinity for vitamins, minerals and other nutrients of feed

NOVUS Solution:

Novus International is an animal nutrition and health company serving the animal agriculture

industry for last 50 years through its innovative and research based solutions and programs

particularly designed to meet the needs and challenges of its customers all over the world. To

control the adverse effects of mycotoxins in feedstuffs and compound feed Novus has a very

unique approach. The solution is based on the use of Toxiban Max in feed to control the

negative effects of mycotoxins and to improve the overall health status of farm animals.

Quality Toxin Binder – Toxiban Max:

For the prevention and control of adverse effects of mycotoxins in dairy animals an innovative

and research based mycotoxin binder “Toxiban Max” is now available all over the Pakistan and

LuteinHepatoprotector

Bentonite - MontmorillionitePassive sequestrant

NaOH dry yeast cell Active sequestrant

LecithinDetoxifier, immune system potentiator

to assure the supply of this quality product at door step of dairy farmers in Pakistan “Marush

International” is serving as sole distributor of “Novus International” and sales and technical

team of company is just available to serve its customers in the depth and breadth of country.

Toxiban Max – Product Specifications:

Toxiban Max is a proprietary blend and its composition is as follows:

Nutrient Specification Composition (Per KG)

Bentonite Montmorillionite 592 grams

Sodium Hydroxide Dry Yeast Cell Wall 226 grams

Lecithin 32 grams

Lutein Carotene Pigment 10 grams

Purified Diatomaceous Earth 125 grams

Silicon Dioxide 8 grams

Calcium Carbonate 7 grams

Bentonite Montmorillionite:

Bentonite is mineral clay and belongs to Phylosilicate Group and chemically it is called as 2:1

Phylosilicate because in its chemical structure it has two tetrahedral sheets and one octahedral

sheet. Due to its unique chemical structure naturally its surface area is very wide but the

Bentonite present in Toxiban Max is unique in this regard that it has been processed further by

using a specific atomic and molecular technology and its surface area has been increased 5 to

10 times more and one gram of this Bentonite contains 300 meter square active surface area.

Due to this molecular technology the each particle of Bentonite is a plate like structure and

average size of each particle is less than 1 µm. These particles carry a negative charge and due

to large surface area net negative charge is very high and has maximum affinity for a variety of

mycotoxins which carry positive charge naturally. In scientific terms this affinity is called as

Cation Exchange Capacity and in Toxiban Max it is 80-100 meq/100 gram.

Sodium Hydroxide Dry Yeast Cell Wall:

This second most important component of Toxiban Max is obtained from common yeast named

as Saccharomyces Cerevisae and its cell wall is rich in Mannooligosaccharides (MOS). MOS is

composed of two basic units such as Mannans and Glucans and in the presence of sodium

hydroxide both these components get separated and work individually. The Beta Glucan

component of MOS has ability to bind mycotoxins due to its typical chemical composition and

the resultant molecule becomes inactive with no further ability to pose toxic effect. Moreover

due to its carbohydrate and protein nature MOS also acts as a growth promoter for animals.

Lecithin Diatomaceous Earth:

The third component of Toxiban Max is a vegetal origin fatty acid named as Lecithin which is an

antioxidant by nature. In Toxiban Max Lecithin has been combined with Purified Diatomaceous

Earth in a way that its antioxidant property has been increased manifold. Lecithin gets absorbed

in blood from intestine and due to its typical chemical structure it undergoes a typical chemical

reaction with any mycotoxin present in blood and changes the chemical composition of that

mycotoxin. The resultant chemical compound is no more a mycotoxin but it becomes a Toxoid

O

CH3 O OH

O

OH

H H

O

O

OH O CH3

OO

CH3 O OH

O

O O

H

H

O

O

O

CH3OOH

O

O

CH3 O OH

O

O

O

O

Pro-binding groups formed react with specific radicals in the molecule of zearalenone

Detoxification of zeara-lenone is produced and a new molecule is formed (toxoid)

Alkali extractionof β-D glucans

[ZEN-β-D-glucan complex]

GLUCANS OBTAINED FROM DRIED YEAST CELL WALL ACTIVELY BIND MYCOTOXINS

YEAST CELL WALL

which further neutralizes the other mycotoxins present in the blood circulation. In this way

Lecithin performs the function of immune surveillance within blood stream and protects the

animal cells from negative effects of mycotoxicosis. By virtue of its chemical nature it also acts

as an intracellular antioxidant and maintains the various body functions.

Lutein Carotene Pigment:

The fourth most important component of Toxiban Max is Lutein Carotene Pigment which is a

typical xanthopyll pigment belongs to Carotene Family. This natural pigment is obtained from a

flowering plant named as Mexican Mary Gold or Tagetes Erecta and its medicinal value has

been already established since ancient times. By nature Lutein is an antioxidant and prevents

the cellular damage within the animal body. In severe mycotoxicosis Lutein helps the animal to

prevent the damage of liver and kidney cells and protects these cells from adverse effects of

mycotoxins and also helps to regenerate the dead and damaged cells.

Toxiban Max – Prevention and Treatment at One Step:

Sodium Hydroxide Dry Yeast Cell Wall and Bentonite Montmorrillionite:

Active and passive binding of mycotoxins stops the absorption of mycotoxins from intestine

Lecithin Diatomaceous Earth:

Lecithin converts toxins into toxoids and provoke immunity against mycotoxins

Lutein Carotene Pigment:

Lutein prevents the cellular damage and helps regenerate the dead cells due to mycotoxins

Feeding Recommendations:

Finished Feeds: 0.5 to 1 KG per Ton of Finished Feeds

Total Mixed Ration (TMR): 0.5 to 1 KG per Ton of TMR on Dry Matter Basis

Individual Animal Dosage: 10-15 Grams per Animal per Day

IQFBentonite

Montmorrillionite

IQFYeast

Cell Wall IQF

Lecithin

IQFLuteinPassive

sequestration Active

bindingDetoxification

by immune surveillance

Protection of end-organ

damage

Response time Rapid acting Longer acting

Level 1 Level 2 Level 3