mycotoxins in dairy cattle
DESCRIPTION
Dr. Anas Ahmad Khan, Ph.D. Country Manager Novus International Pakistan Mobile: +92 300 8111681 & +92 301 8111681 Phone: +92 51 8441031 Fax: +92 51 8441032TRANSCRIPT
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