GH. SADEGHI University of Kurdistan Use of Antimicrobial and Detoxifier Agents For Poultry Feed Safety By: GH. SADEGHI PhD of Poultry Nutrition University of Kurdistan Kurdistan, IRAN GH. SADEGHI University of Kurdistan Basic Fact • In addition to the essential nutrients, feeds may contain organic and inorganic materials that have various effects on poultry: – beneficial, detrimental or negligible – they can affect growth, health or the processed product – may be naturally occurring, intentionally or unintentionally added – can be produced via microbial growth GH. SADEGHI University of Kurdistan Feed Ingredients Contamination • Contamination of feeds may be take place in different stages: • Pre-harvest (pesticides and other agrichemicals) • Post-harvest • During Feed Processing • During Feed Storage GH. SADEGHI University of Kurdistan Contaminants of Feeds • Chemicals: • Dioxins, pesticides and other agrichemicals • Drug Residues • Heavy metals: • lead, mercury, and cadmium. • Pathogen Microbs: •Salmonella • Microbial Toxins: •Mycotoxins: Aflatoxin, Ochratoxin, etc. GH. SADEGHI University of Kurdistan Pathogens in Feed • Most important pathogen in poultry feed is Salmonella. • The major sources of salmonella for poultry are the bird themselves, feed and environment. • Establish HACCP programs across the animal feed industry to minimize Salmonella. • Implement a Salmonella-negative standard for animal feed. Drug Residues • Medicated feeds left over in the equipment from one batch may contaminate the next batch of feed that is not medicated. GH. SADEGHI University of Kurdistan Gizzerosin •This is a toxic compound found in fish meal, a typical feed ingredient • It is formed by the reaction of amino group of lysine with the imidazolyl ethyl group of histamine during the dry heat processing •Comes from improper storage of raw fish prior to production of fish meal •Causes a reduction in growth rate •Usually comes from fish with“dark” or “red” meat and free histidine in the soluble fraction of protein GH. SADEGHI University of Kurdistan Gizzerosin • Gizzerosin stimulate H2-receptors in proventriculus , causes an excessive HCl secretion and sever decrease in pH at the proventriculus and gizzard, causes damage to koilin layer and submucosal of gizzard • several dietary treatments for gizzrosine toxicosis have been tested including supplementation of: • H2-histamin receptor antagonist cimetidin • Antacid compounds sodium bicarbonate and magnesium trisilicate GH. SADEGHI University of Kurdistan Bioterrorism? Bioterrorism: What is it? The intentional or threatened use of microorganisms or biological toxins to kill or incapacitate people, animals, or crops. Toxins as Bioweapons: Toxin: Any toxic substance produced by an animal,plant, or microbe. Some toxins are produced by molecular biology techniques or Chemical synthesis. GH. SADEGHI University of Kurdistan Microbial Toxins in Commercial Feeds •Usually produce by microbes • Microbes need enough CHO, moisture and O2 to produce these toxins •Commercially-processed feeds are less likely to have these toxins •Not destroyed by steam pelleting or extrusion •Most important microbial toxins in poultry feed industry are mycotoxins GH. SADEGHI University of Kurdistan Mycotoxins •The more important toxins affecting animal feeding are those associated with molds •These are called “mycotoxins” •Three important genera are: • Aspergillus • Penicillium •Fusarium •They exist and grow anywhere as long as there is enough COH substrate, no less than 14% moisture, adequate temperature, oxygen GH. SADEGHI University of Kurdistan Mycotoxins •Usually produced in feedstuffs prior to harvest, but also result from poor storage •Most important naturally occurring mycotoxins are : Aflatoxin Ochratoxin Trichothecenes (Deoxynivalenol) Zearalenone Fumonisin GH. SADEGHI University of Kurdistan Mycotoxins Mycotoxins may be: Carsinogenic: Aflatoxin B1, Ochratoxin Nephrotoxic : Ochratoxin, Citrinin Nerotoxic : Fumonsin B1 Estrogenic : Zearalenone Dermonecrotic : Thricothecens GH. SADEGHI University of Kurdistan Mycotoxins •Tow type of fungi can be recognized in contaminated grains: •Those that preferably infect stored grains (saprophytic) • Those which attack the plant in the field (Phtopathogenic) •The environmental factors that determine fungal growth and mycotoxin production in feeds are related to: • substrate itself (intrinsic factors) • storage condition of substrate ( extrinsic factors) GH. SADEGHI University of Kurdistan Factors affecting mold growth and mycotoxin production in creral grains Intrinsic factors Extrinsic factors Ingredient composition(lipids, CHO, trace Relative humidity: RH greater than 70% metals,etc. favors fungal growth pH: Fungal growth decrease with Environmental temperature: the optimal decreasing pH temprature for fungal growth and mycotoxin production varies with the spices. Grain moisture: optimal grain moisture is O2/CO2: Fungi are aerobic organisms. >13% for saprophytic and >20% for Studies with mycotoxigenic Fusaria phytopathogenic fungi showed that in storage atmosphere containing 5% O2 and 40% CO2, fungi growth affected and no mycotoxin are produced Water activity (aw): this parameter is Surface area of grain: smaller particles related to the water that is actually have increased surface area which available for fungi growth predisposes mold growth Adapted from Lesson et al. 2001 GH. SADEGHI University of Kurdistan The affects of mycotoxins on poultry •Mycotoxins can result in vomiting, diarrhea, internal bleeding •Mycotoxins can impair absorption of A, D, E, and K • Spiking syndrome causes mortality in broilers, suggested mycotoxins levels are high, thiamin should be increased GH. SADEGHI University of Kurdistan The affects of mycotoxins on poultry • Fungi can also adversely affect poultry performance by altering the nutritional composition of the substrate during their primary metabolism, without producing secondary metabolites (Mycotoxins) • Fungal growth can: •Decreases the density and energy content of the grain( mold use TG and produce CO2) • Alter grain vitamin content (thiamin by producing thiaminase) • Alter grain amino acid content GH. SADEGHI University of Kurdistan AFLATOXIN AFLATOXIN B1 GH. SADEGHI University of Kurdistan Aflatoxin • Aflatoxins are a family of mycotoxins that are produced mainly by toxigenic strains of Aspergillus flavus and A. parasiticus. • The name aflatoxin is derived from the bacteria that produce it: Aspergillus (a-), flavus (-fla-), and toxin. • In 1960, aflatoxins made a name for themselves by killing 100,000 turkeys in England that were found to be eating moldy ground peanuts. GH. SADEGHI University of Kurdistan Aflatoxin •Aflatoxin is the mycotoxin of greatest concern in feeding of poultry •both outright toxic and carcinogenic •liver (hepatoma) and blood clotting problems •traditionally, sources include corn, cottonseed and peanuts •aflatoxin contamination varies year to year •Aflatoxins (moldy feed) inhibit microbial intestinal synthesis GH. SADEGHI University of Kurdistan Aflatoxin GH. SADEGHI University of Kurdistan The Affects of Aflatoxins on Poultry • A dose of 0.25ppm in turkey poults and ducklings impairs growth, • A dose of 1.5ppm in broilers and 4ppm in Japanese quail also has a negative affect on growth. • An increase in blood clotting time increases the susceptibility of the carcass to bruising even at doses below that to have an affect on growth. • In poultry, aflatoxins impair the availability of bile salts, which decreases Vitamin D3 production. This causes a decrease in the absorption of fat-soluble vitamins. GH. SADEGHI University of Kurdistan The Affects of Aflatoxins on Poultry • Aflatoxins also decrease the production of Vitamin A in the liver, and it has secondary effects such as decreased blood calcium levels, decreased bone strength, and a decreased tissue and serum tocopherol level. This decrease in tocopherol levels can lead to Vitamin A and E deficiencies. GH. SADEGHI University of Kurdistan Trichothecenes • T-2 toxin and other trichothecenes (HT-2) can cause mouth and intestinal lesions as well as impair the birds immune response, causing egg production declines, decreased feed consumption, weight loss, and altered feather patterns. • While much is yet to be learned, T-2 toxin and related compounds are currently thought to be most potent from Fusarium mycotoxins for poultry GH. SADEGHI University of Kurdistan Ochratoxin •These are compounds produced by Aspergillus and Penicillium molds •Widely found in nature •Typically associated with kidney toxicity •Most mold toxins also destroy nutrients in feeds •example: Pseudomonas can separate glutamic acid from folic acid, making it ineffective GH. SADEGHI University of Kurdistan FUMONISINS • Fumonisins are the most recently discovered group. • They are produced by the fungus Fusarium moniliforme • Fumonisin B1 is the most predominant molecule • Fumonisin inhibit of sphingolipid biosynthesis or sphingosin turnover because of the similarity of polyhydric alcohol miotey of FB1 to the complex amino alcohol sphingosine GH. SADEGHI University of Kurdistan STEREOCHEMISTRY OF B SERIES FUMONISINS GH. SADEGHI University of Kurdistan GH. SADEGHI University of Kurdistan GH. SADEGHI University of Kurdistan Clinical guide to major mycotoxins in poultry Mycotoxin Type of bird Dietary Main effect level Aflatoxin Broiler chicken 3 ppm No detrimental effect after 2 weeks of exposure Laying hens 2.5 ppm Minimal dietary concentration can affecting performance when given for 3 weeks or more Ochratoxin A Broiler chicken 1.5 -2 ppm Minimal dieary level capable of reducing weight gain 2 -4 ppm Increased relative weight of kidney, liver; decreaseed relative weight of thymus and bursa Trichotecenes: Broiler chicken 1 -4 ppm Oral lesions, decrease FI and WG, abnormal feathering T2 toxin and DAS 1-2 ppm Oral lesions, decrease FI and egg production Adapted from Lesson et al. 2001 GH. SADEGHI University of Kurdistan Prevention of mycotoxicosis •Transgenic Strategies to Reduce Mycotoxins in Crops: Reducing infection by the fungus Degrading the mycotoxin in planta Disrupting mycotoxin biosynthesis Inducing insect resistance • Bt CORN HYBRIDS Transgenic corn with the Bt gene for insect resistance is a promising solution to the fumonisin problem GH. SADEGHI University of Kurdistan Prevention of Microbial Growth in Feed • Microorganisms require unbounded water to growth in feeds. • Feeds containing more than 12-14 % moisture can support bacterial, mold, and Yeast growth unless they are frozen. • In semi- moist feeds at room temperature (22oC),mold growth is visible within 3 days. • There are 3 approach to control microbial growth: • Use of antimicrobial agents • Use of special packaging • Use of water absorbents material GH. SADEGHI University of Kurdistan Antimicrobial Agents • Over 20 compounds are used in the feed industry to inhibit fungal or microbial growth. • Some have general and some specific application in feed product: • The Benzoates and Parabens are wide spectrum antimicrobials • propionate are used primarily to inhibit yeasts and molds, but are also effective against bacteria, fungi and yeast. • An intelligent choice of an antimicrobial include: • study of specific microbial problem • solubility and ease of application of the agent • pH requirement • effect of antimicrobial agent on palatability GH. SADEGHI University of Kurdistan Antimicrobial Agents used in feeds Name Limit or Restriction Benzoic acid 0.1 % Formic acid 2.5 % Propionic acid None Sorbic acid None Calcium propionat None Calcium sorbate None Potassium sorbate None Potassium bisulfate Not for use in B1 sources Potassium metabisulfate Not for use in B1 sources Methyl paraben 0.1 % Propyl paraben 0.1 % GH. SADEGHI University of Kurdistan Antimicrobial Agents used in feeds Cont. Name Limit or Restriction Sodium benzoate 0.1 % Sodium bisulfate Not for use in B1 sources Sodium metabisulfate Not for use in B1 sources Sodium nitrite 0.002 % Sodium propionate None Sodium sorbate None Sodium sulfite Not for use in B1 sources GH. SADEGHI University of Kurdistan Especial Packaging • Control of spoilage in semi-moisture product (18-36% moisture) is not simply a matter of adding antimicrobial agent. • If feed microbial load is higher than 500,000 CFU, it is difficult to control spoilage with antimicrobial agents. • A second means of controlling spoilage is by the use of special packaging . •The aim of this process is to reduce O2 tension in the feed package during storage to restrict the growth of aerobic microorganisms. • Thus, an inert gas, such as N2 or CO2 is introduce into the bag before it sealed. • this method is more applicable in fish feed industry GH. SADEGHI University of Kurdistan Water Absorbents Material • Microorganisms require an abundant supply of water to growth, therefore, reducing the supply of water in a feed is an effective way to limit their growth. • A third approach to controlling spoilage in feeds is by controlling the water activity (Aw). • Aw: the ratio of the water vapor in the feed to the vapor pressure of pure water at the same temperature • Aw of pure water is 1.0 and n feeds is less than 1.0 • The Aw for microorganisms growth are: • 0.91 for bacteria • 0.88 for yeasts • 0.80 for molds GH. SADEGHI University of Kurdistan Water Absorbents Material • water exist in feeds in 3 forms (liquid, vapor and chemically bound • Control of Aw in feeds involve increasing the proportion of bounded water, thereby decreasing the proportion present as a liquid (free). • It is possible to achieve Aw values in suitable range by the addition of compounds such as: NaCl Propylene glycol Other dry feedstuffs (grains) GH. SADEGHI University of Kurdistan Detoxification of mycotoxin-contaminated feeds • Different strategis developed to control of mycotoxicosis include : • Physical Methods • Chemical methods • Physical methods include: • Extraction with organic solvents • Heat inactivation • Irridation • Adsorption by adsorbents • Chemical methods include: • Ammoniation • treatment with oxidizing agents • treatment with organic acids GH. SADEGHI University of Kurdistan Organic solvent extraction • Several solvents or mixture of solvents can effectively extract mycotoxins( especially aflatoxins) from feeds include: • 95% Ethanol • 90% aqueous acetone • 80% isopropanol • hexane – ethanol • hexane – methanol • hexane – methanol – water • methylene chloride (CH2Cl2 ) GH. SADEGHI University of Kurdistan Heat inactivation •Aflatoxins are very resistant to thermal inactivation, but some research works showed that roasting significantly reduced the concentration of aflatoxin in peanuts that AFB1 have been reduced by 50 – 70 % Irradiation •A marked reduction in the concentration of aflatoxins in contaminated products has been showed. • Peanut oil exposed to short wave and long wave UV light showed a significant reduction in aflatoxin level • A 14 hour exposure to sunlight destroyed 50% of AFB1 in peanut flakes GH. SADEGHI University of Kurdistan Adsorbents • Adsorbents are compounds that are not absorbed from the GIT and have ability to bind physically with chemical compounds, precluding their absorption. • Adsorption therapy has been one of the most important method of preventing the absorption of ingested toxins. • However, adsorbents will also bind concurrently administered drugs used for therapeutic purposes. • The use of adsorbents have been extensively studied in livestock exposed to dietary aflatoxins. GH. SADEGHI University of Kurdistan Adsorbents • Different adsorbents are used include: • Activated charcoal • 200ppm and or 0.2 - 0.5 g/kg • Hydrated sodium calcium aluminosilicate (HSCAS) • 0.5 % • Sodium bentonite • 0.5 % GH. SADEGHI University of Kurdistan Detoxification by ammoniation • Ammonia or ammonia-related compounds have the most practical application • Ammoniation of contaminated corn, cottonseed, cottonseed meal and peanut meal has been shown to reduce the aflatoxin level by greater than 99% • Primarily 2 procedure are used: • HP/HT: used in feed mill use 0.2-2% ammonia, 20-60min 35-50 psi, 80-120 oC • AP/AT: used in farm • Use 1-5% ammonia, 2-3 week GH. SADEGHI University of Kurdistan Detoxification by oxidizing agent • Other chemical method is Hydrogen peroxide (H2O2) • It is an oxidizing agent that destroy up to 97% of aflatoxins Detoxification by organic acids • Treatment of maize with following organic acids has reduced the infection with Aspergillus flavus fungi and decreased aflatoxin production after 6 months. • Isobutyric acid • Propionic acid • Acetic acid GH. SADEGHI University of Kurdistan CONCLUSIONS The ultimate solutions to the global feed toxins, especially mycotoxin problem are: Reduction of fungal infection and mycotoxin levels in crop plants in the field and in storage. Novel strategies need to be developed such as the reduction of fumonisin levels in genetically modified Bt corn. Detoxification of contaminated feedstuffs by suitable methods And finally by inform poultry producers about the health hazards of mycotoxins GH. SADEGHI University of Kurdistan ??? questions? سنندج ?Questions از توجه شما سپاسگزارم GH. SADEGHI University of Kurdistan • growing poultry should not receive more than 20 ppb aflatoxin in the diet. However, feeding levels lower than 20 ppb may still reduce their resistance to disease, decrease their ability to withstand stress and bruising, and generally make them unthrifty • Laying hens generally can tolerate higher levels than young birds, but levels should still be less than 50 ppb • Aflatoxin contamination can reduce the birds’ ability to withstand stress by inhibiting the immune system. • This malfunction can reduce egg size and possible lower egg production. • In addition, one must pay special attention to the use of contaminated corn in layer rations because eggs are GH. SADEGHI University of Kurdistan Prevention of mycotoxosis • The best way to prevent aflatoxicosis is to prevent the infection of the feed by Aspergillus if moisture content is kept below 14% and temperature is kept below 25 degrees Celsius, then mold will have a difficult time surviving. • Unfortunately, there are problems with chemical treatment of infected crops. What ever treatment is used adds to the cost of production and none of the processes are 100% effective. Some treatments may decrease the food value of the crop, and some chemical treatments may produce secondary biologically active agents that may also be GH. SADEGHI University of Kurdistan •` Mixing of corn with dry grain has shown to help decrease moisture content of the stored material below the level that mold can begin to develop • Also, high CO2 levels along with decreased humidity have been shown to decrease aflatoxin levels • The most effective and practical method of detoxification of contaminated grain is ammoniation. This can kill up to 99% of mold growth Proprionic acid has very little effect • Also, the pretreatment of food with Phenobarbitals or diethyl stilbestrol, used as dietary supplements, will help reduce the effects of aflatoxins by binding to them and preventing their breakdown and absorption. GH. SADEGHI University of Kurdistan • Clay minerals and hydrated sodium calcium alumiosilicate at levels as low as 0.5% of dietary intake, can also help reduce the effects of aflatoxins in the body.
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