feed additives

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Food additives
growth promoters:
improve the production traits of healthy animals
• Antibiotics: produces by other microorganisms, fungi that protect
the growth of bacteria
– reduce the number of pathogenic bacteria (E. coli, Salmonella
sp., etc.), prevent the infection of the digestive tract,
– increase the absorptive capacity of the small intestine (decrease
the thickness of the intestinal wall)
– reduce the competition of bacteria with the host (bacteria
ferment the nutrients before digestion)
– they have been used mainly in pig and poultry nutrition
– their widespread use could cause the ability of certain strains to
be resistant to many antibiotics
– therefore in the EU the use of antibiotic growth promoters has
been restricted since 2000
• Probiotics: live microbial food supplement
– containing mostly lactic acid producing bacteria
– by reducing the pH in the intestine, reducing the numbers of harmful
bacteria (competitive exclusion)
– enhance immune competence
– are heat sensitive (pelleting)
• Prebiotics: oligosaccharides (2-20 monosacharides) that modify the
balance of the microfloral population by promoting the growth of the
beneficial bacteria
– can be fermented by the favourable bacteria
– decreasing the attachment of harmful bacteria with the gut wall
– galactooligosaccharides (GOS) (legume seeds)
– fructooligosaccharides (FOS) (cereal grains)
– mannanoligosaccharides (MOS) (yeast cell walls)
• Symbiotics: contain both probiotics and prebiotics
• Organic acids: (lactic acid, formic acid, fumaric acid, citric acid,
propionic acid etc.)
– stabilise the intestinal microflora by decreasing the pH
– can be effective in early weaned, young animals
– incorporated into the diet (6-25 g/kg) or into the drinking water
• Enzymes:
– as a result of advances in biotechnology, more effective enzyme
preparations can be produced relatively inexpensively
– supplement the insufficient enzyme secretion of young animals
(amylase, protease, lipase etc.)
– can improve the availability of plant storage polysaccharides (starch,
oils and proteins) by degrading the cell wall content like cellulose by
the enzyme cellulase (5-10% improvement can be achieved in poultry
and pig trials)
– destroy ant-nutritive materials that interfere with the digestion and
utilisation of nutrients (glucanase, xylanase destroy cereal cell wall
compounds, β-glucans and arabinoxylans)
– phytase releases phosphorous and other minerals from phytic acid in
cereals and oilseeds (greater availability of minerals, less need for
inorganic phosphorous, beneficial effect on the environment)
• Flavory materials: (sugars, vanilla, canella etc.)
– increase the feed intake
– can be effective mostly in young intensively growing animals
– their effect depends on the flavour sensation of different animal species
Effect of -glucanase enzyme supplementation on
the growth of broiler chicks
control
enzyme
wheat content of the diet
• Plant extracts, essential plant oils: (sage, peppermint, garlic, thyme etc.)
– can be used for the partial replacement of antibiotics
– complex effects (flavour materials, antimicrobial compounds,
antioxidants etc.)
– the products in the practice are mostly the mixture of different plant
extracts and oils
– their market share is increasing in Europe
b., other food additives
• NPN materials: (urea, ammonium salts)
can be used in ruminant animal nutrition
mostly in low milk producing cows, beef cattle
they are strict rules for using them
• Toxin binders: used for binding mycotoxins (zearalenon (F2); T2 toxin;
ochratoxin, deoxynivalenol (DON), fumonisins, aflatoxin etc.), decrease their
absorption
aluminium silicates (bentonit)
glucomannans (yeast cell wall extracts)
they efficiency is toxin dependent
bind also some minerals and nutrients
• crystallinene amino acids:
– L – lysine
– DL – methionine
– in the near future threonine, tryptophan and arginine will also be available in the
feed industry
– for ruminants must be fed in by pass form (covering by fatty acids, protecting
against the bacterial degradation)
– can be optimise the amino acid composition of food proteins
– can be decreased the protein content of diets
– the price of compound feeds can be cheaper
– decrease the N-excretion
• colour materials: carotenoids (zeaxanthin, lutein, licophin, capsanthin etc.)
– egg yolk
– skin, the fat below the skin
– using is synthetic colour compounds is limited in the EU
•antioxidants: protecting vitamins and fatty acids from the oxidation
– synthetic antioxidants
– etoxi-methil-quinolin (EMQ)
– butil-hidroxi-toluol (BHT)
– natural antioxidants (vit. E, vit. C, carotenes etc.)
– they need depends on the fat and unsaturated fatty acid content of the diet.
INVESTIGATION THE IN VITRO BINDING EFFICIENCY OF
DIFFERENT TOXIN ADSORBENTS ON MYCOTOXINS AND
MICROELEMENTS
OBJECTIVES
The main goal of this research was to determine the in vitro binding efficiency of
some toxin binders for different mycotoxins and microelements
METHODS
Five different commercial adsorbents (Zeolit, Toxy-Nil, Redutox, Mycofix 3.E
and Mycosorb) were tested in 4 replicates for ochratoxin A (OTA),
zearalenone (ZON), T-2 toxin and deoxynivalenol (DON). Besides testing the
toxin binding efficiency, the effect of adsorbents on the iron, copper,
manganese and zinc was also determined. The in vitro model employed
simulated the in vivo conditions (pH, transit time) of the poultry
gastrointestinal tract. The amounts of adsorbents, purified toxins and
microelements were determined according to their practical occurrence or
recommendations.
CONCLUSIONS
•
•
•
The binding efficiency of the investigated adsorbents was toxin
dependent. The highest values were found for ZON (57-69%),
while the lowest for DON (25-30%). The highest difference
among adsorbents was found in the case of OTA (27-42%).
Binding affinity for T-2 toxin ranged between 27 and 37%.
Zeolite bound zinc at 11%, the other 3 microelements in a
significant higher ratio (34-44%). The other adsorbents showed
lower, but still significant affinity for the microelements 12,516,5% for cupper, 5-17% for zinc, 6-14% for iron and 6,5-22,7%
for manganese.
From the results it can be concluded, that the efficacy of toxin
binders used in this experiment is only limited for ZON, DON,
OTA and T-2 toxin and they can bind beside mycotoxins also
significant amount of micro nutrients. Further in vitro and in vivo
studies needed to determine the toxin binder specific mineral and
vitamin supplementations of poultry diets, if these types of feed
additives are used.
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