Management of Safety in the Feed Chain
A prerequisite for the production of safe food of animal origin is safe feed. Over the last decades, a series of food safety incidents occurred, taking their origin in feed (BSE agent in meat and bone meal, PCBs/dioxins in fats and bread meal, melamine in protein concentrates, etc.). An effective feed safety management system is key to ensure the safety of products of animal origin. However, feed safety is not just about preserving the safety of animal products: any feed safety management system should address both human food safety and animal health and welfare. In certain countries such as those in the EU, operators are also required to take into account in their risk management system the potential negative impact of contaminants on zootechnical performance. On top of these safety considerations, market specifications excluding certain ingredients (e.g. non-GMO feed or organic feed) impose additional constraints on operators in the feed chain. These are not addressed in the present article.
OVERVIEW OF THE FEED CHAIN
The feed chain is extremely complex as it involves interactions with many sectors: feed is a main input to the production of food but the food chain generates itself at different processing stages. Co-products can be found in the feed chain, and even part of foodstuffs, which are withdrawn from the food market for logistical reasons or because they have exceeded the use-by date (so-called former foodstuffs), may also be used for feed purposes. The feed chain cannot therefore be represented linearly (see Figure .1). When it comes to safety management, the impact of this iterative process on, e.g., concentration of contaminants is essential. The feed chain interacts also with a number of other sectors whose core business (and level of interest/consideration) is often not the feed outlet (biofuels industry, chemical industry, mining companies, etc.). This also has to be taken into account when considering risk management in the feed chain. The feed market is global, in particular as regards unprocessed cereals and co-products from the biofuel and crushing industry. Operators involved in the feed chain may be classified in five main categories:
● Producers of feed ingredients: these may be farmers producing crops or processors of vegetable products, produce from the biofuel industry or producers of feed additives, etc.;
● Traders, transporters, warehouses;
● Premix manufacturers, mixing certain feed additives on a carrier;
● Compound feed manufacturers mixing feed ingredients with premixes to produce a complete or complementary feed;
● Livestock holders who produce their own feed (home mixers) and/or deliver feed to animals.
CHARACTERISTICS OF THE FEED CHAIN
An understanding of certain features of the feed chain is important for managing its safety and realizing the extent of the challenges. Feed is defined by Codex as “Any single or multiple materials, whether processed, semi-processed or raw, which is intended to be fed directly to food producing animals.”
CHARACTERISTICS OF THE FEED CHAIN
FIGURE .1 Functioning of the feed chain (FEFAC 2009).
There are four extensive categories of feed with different risk profiles:
- Feed additives defined by Codex as “Any intentionally added ingredients not normally consumed as feed by themselves, whether or not they have nutritional value, which affect the characteristics of feed or animal products”: these are chemically well-defined substances which are added to the diet to exert a specific function, whether nutritional (vitamins, etc.), technological (binders, etc.), sensorial (flavorings, etc.) or zootechnical (enzymes, etc.). In several countries these feed additives are subject to an authorization procedure based on a risk assessment and are often subject to restrictions in terms of dosage or target species. The EU register of feed additives includes more than 2800 substances.
- Premixes: these are uniform mixtures of micro-ingredients and feed additives on a carrier to facilitate their even distribution in a larger mix. Premixes are often dedicated to a given target species.
- Feed materials: these are feed from vegetable, animal or mineral origin, which can be classified in four main categories: a. Forages (grass, silages, straw);
b. Unprocessed feed materials, i.e. feed crops such as peas or feed wheat or the surplus of food crops;
c. By-products of the food, drinks and biofuel processing industries (e.g. bran, beet pulp, rapeseed meal, distiller’s grains, soya meal, fish trimmings, etc.) or former foodstuffs
(surplus of bread);
d. Minerals such as phosphates, limestone, etc.
In several countries, inventories of feed materials have been established, such as in the USA (AAFCO list). In 2011, the EU published a non-exhaustive catalogue of feed materials (Regulation (EC) No. 575/2011), which includes almost 600 feed ingredients. Next to this catalogue, a register of feed material (www.feedmaterialsregister.eu), where EU operators are bound to notify the placing on the market of any feed material not listed in the catalogue, counts more than 2000 additional feed materials.
- Compound feed: a compound feed is a mixture of several feed materials, whether or not with feed additives. Compound feeds are manufactured to meet specifications prepared by specialists in animal nutrition providing the required nutritional needs according to the particular species of animal and its growth stage or position in the production cycle. The compound feed manufacturer may be a specialized company or the farmer himself. Compound feed may be complete, i.e. sufficient to meet the animal’s needs, or complementary (or concentrate), i.e. they must be distributed to animals together with other feed. The manufacturing of compound feed involves various categories of operators, i.e. the producers of the feed ingredients (feed additives or feed materials), the premix manufacturer and the compound feed manufacturer.
The diet of ruminant animals is composed in general of forages, completed by other feed materials whether or not mixed in the form of a complementary feed. The proportion of feed other than forages in the ruminant diet will vary according to the level of intensification of the production system. Monogastrics (poultry, pigs, etc.) do not get forages.
The key features of the feed chain from a feed safety management point of view are the following:
● A huge number of feed ingredients and variety of risk profiles (see above): not all feed ingredients are used at the same time. A compound feed usually contains between three ingredients for the simple mixtures and up to 30 ingredients for elaborate compound feed (half being feed additives). An average composition of a compound feed in the EU is given in Figure .2. The most important feed ingredients are cereals incorporated at more than 50% and oilseed meals. However, the type of ingredients, their number and their incorporation rates in compound feed vary significantly depending on the species of destination and also on the availability and the quotations of the feed ingredients, which depend on the location of the compound feed manufacturing plant.
● A vast number of feed chain operators and origins: the risk profile of a feed may be affected at any stage of its life cycle: primary production (i.e. mining company, crop producer or chemical company), transport, handling, storage, intermediate processing (food or biofuel industry), mixture with other feed ingredients and distribution to animals. The risk at the
CHARACTERISTICS OF THE FEED CHAIN 28% Source: FEFAC
FIGURE .2 Average composition of a compound feed produced by industrial compound feed manufacturers in the EU in 2011.
first stages of the chain (feed additives and feed materials production) is the introduction of hazards in the feed chain (e.g. contaminants such as dioxins) whereas the risk at the premix and compound feed stages is mistakes in the formulation of the feed or cross-contamination. This means that an efficient risk management strategy in the feed chain should aim at preventing the introduction of hazards at the first stages of the chain, whereas controls at the subsequence stages should focus on the control of formulation and cross-contamination. It should also be stressed that each stage of the chain has the potential to extend the scope of an incident through the multiplication of operators involved, meaning that an incident occurring at the beginning of the chain has a potentially larger impact than if occurring at the end. A large proportion of certain feed materials such as soybean meal are subject to international trade, and the number of potential geographical origins is also an important dimension to be considered for feed safety management.
● The different animal species: the toxicity of contaminants is not the same for all animal species and the transfer of contaminants from feed to products of animal origin is also species specific. As compound feed manufacturers often produce feed for several categories of animals, the animal species is an additional dimension to the risk analysis. Furthermore, certain feed ingredients may be restricted for use by certain species only. The risk of cross-contamination during transport or storage of feed ingredients or within the feed mill between batches of compound feed destined to different animal species must also be taken into account by the feed businesses in their feed safety management procedures (Figure .3). The same applies for those feed manufacturers involved in the manufacturing and delivery of medicated feed.
It can be concluded that, in some respects, feed management of feed safety is more complex than often realized and presents challenges of a different nature than food safety. This means that, for products which may be used either as food or feed, the results of a food safety assessment, although useful information, are not sufficient to guarantee the safety
FIGURE .3 Schematic representation of the compound feed manufacturing process.
of the product as feed. However, the principles and approaches used to assess and prevent potential hazards in feed are similar to those prevailing in the management of food safety.
A proper risk management requires a solid risk assessment, which starts with hazard identification.
Feed hazards associated with human or animal health issues may be of biological (prion, pathogenic microorganisms, parasites), chemical (heavy metals, dioxins, mycotoxins, glucosinolates, excessive levels of pesticides, veterinary medicinal substances or additives, adulterants) or physical origin. Products of their biotransformation in edible products shall also be considered (e.g. aflatoxin B1 in feed transformed into aflatoxin M1 in milk). These hazards may be introduced with source materials or via carry-over or cross-contamination during handling, storage, transport and manufacturing. The presence of these hazards may be natural (development of mycotoxins in crops), or due to inadequate process control (dioxin formation during heating, carry-over), bad hygiene practice (Salmonella, use of contaminated raw materials or processing aids) or fraud (deliberate adulteration with products not destined for feed). All these hazards are potentially harmful for animals and/or consumers of animal products. Certain mycotoxins are harmful to animals but are not transferred to animal tissues and do not pose a risk to human health. On the other hand, some hazards such as specific Salmonella serotypes may not be harmful for certain animal species but may be so for human health if present in animal products.
The Codex Task Force on Animal Feed started establishing guidance for governments in prioritizing their national feed hazards. They base their work on the IFIF/FAO manual of Good Practices for Animal Feeding (covering activities by the feed industry, grazing and forages, home mixing and distribution of feed to farm animals), which establishes a current non-exhaustive list of hazards of importance for feed safety, based on the following criteria:
● Relevance of the hazard to public health;
● Extent of occurrence in feed for food producing animals and food of animal origin; ● Potential impact on international trade in feed and food.
This list has been completed to take into account hazards of relevance for animal health as well and has been sorted by categories.
Pathogenic microorganisms in feed may transfer to food-producing animals and then to animal products. They may be introduced into pastures, forages/silages (Clostridium spp., Brucella) or may be present in feed from animal origin, e.g. dairy products, animal meals (Salmonella), and/or may be introduced to feed by cross-contamination or carry-over during processing, transport and storage.
Some animal endoparasites, such as Echinococcus, Toxoplasma gondii and Cysticercus and Trichinella, are human health hazards and may contaminate pasture and forages.
Prions are responsible for the transmission of transmissible spongiform encephalopathies (TSEs). They may be present in ruminant protein meals and are extremely resistant to denaturation by chemical and physical agents including heat. The Codex Code of Good Practice for Animal Feeding recommends that animal products that could be a source of BSE should not be used for feeding directly to, or for feed manufacturing for, ruminants.
Elements which have a relatively long chemical or biological half-life will tend to accumulate in edible products after repeated exposure. The following are non-exhaustive examples:
● Arsenic, found typically in minerals in inorganic form and in fishmeal in the less toxic organic form.
● Cadmium, in particular in minerals (such as phosphate and zinc sources) and in forages. The risk of contamination is greater in crops produced on soil where contaminated manure, sewage, sludge or phosphate fertilizers have been spread.
● Lead may occur in grain or forage grown on contaminated soil and also as a contaminant in minerals.
● Fluorine can be found in particular in feed ingredients of marine origin.
● Radionuclides including caesium-134, caesium-137, strontium-90 and iodine-131, when present in animal feed and forages, may transfer to edible products. They may arise from water or windborne environmental contamination.
Mycotoxins are found most commonly in cereals (especially wheat, sorghum and maize) but can also be found in oilseed meals and cakes, and silage. The most significant mycotoxin from a food safety point of view is aflatoxin B1, which is transferred into milk in the form of aflatoxin M1. Its presence on the outer part of the grains means that most food processes tend to concentrate the mycotoxins in the co-products such as brans or middlings.
Mycotoxin contamination in feed may occur on the field or during storage. Transfer from feed to edible products has been demonstrated for aflatoxin and, to a lesser extent, ochratoxin A. Other mycotoxins such as zearalenone, deoxynivalenol and fumonisin have no or limited transfer to food but can pose serious risk for animal health, animal welfare, in particular for young animals such as piglets, or affect significantly animal performance.
Terrestrial Plant Toxins
Toxin-producing plants may occur in grasslands used for forage or in certain crops. Toxins can include pyrrizolidine alkaloids, ergot alkaloids and other alkaloids (e.g. atropine, caffeine, cocaine, ephedrine, morphine, nicotine, solanine), terpenes (e.g. camphor, menthol, pinene), tetrahydrocannabinol, gossypol, isoflavones and glycosides (e.g. glucosinolates, cyanogenic glycosides, digitalis).
Toxins produced by bacteria such as Bacillus spp., Clostridium botulinum, C. perfringens or Staphylococcus aureus are acutely toxic to food-producing animals when ingested with feed. Transfer of toxin to edible products is therefore unlikely.
Many organic chemical contaminants that are present in the environment may contaminate feed. The lipophilic compounds such as dioxins and some organic chemicals such as organochlorine pesticides (e.g. aldrin, dieldrin, DDT) have the greatest tendency to accumulate in the environment and in edible products of food-producing animals, in particular milk and fats. Some of these substances are classified as persistent organic pollutants and subject to prohibition of use by international agreements such as the Stockholm Agreement.
The duration of exposure is an important element to take into account in the risk analysis in case of contamination.
Dioxins are the most emblematic group of hazardous chemicals including polychlorinated dibenzodioxins (PCDD), dibenzofurans (PCDF) and dioxin-like polychlorinated biphenyls (DL-PCBs). The different congeners hold different levels of toxicity.
A number of cases of contamination of animal products with dioxins with a feed origin have been reported over the last 20 years (see Table .1). The reason for this is the multiplicity of contamination sources, e.g. by direct contamination due to bad practices (e.g. from use of wood tainted with dioxin-containing preservatives as a carrier of premixture)
TABLE .1 Non-exhaustive List of Cases of Contamination of Feed with Dioxins in the EU over the Last 15 Years
Year Product Origin
1998 Dioxin in citrus pulp pellets Process (contaminated limestone)
1999 Feed fats Fraud (disposal of waste oil)
1999 Kaolinitic clays Natural (prehistoric fire)
2000 Choline chloride Process (use of treated wood as carrier)
2002 Carbosan copper Process
2003 Dried fodder Process (direct drying with treated wood)
2004 Potato pulp Process (use of contaminated clay)
2008 Bread meal Process (drying using contaminated fuel oil)
2010/2011 Feed fats Mixing with technical fatty acids (under investigation)
of hazardous waste such as mineral oils in the feed chain) or from combustion sources (e.g. waste incineration plants, fossil fuel power stations, bush fires, exhaust gases). Dioxins may also be present in mineral sources, such as clays (due to prehistoric forest fires), recovered copper sulfate and zinc oxide. Fish meal and fish oils may present high levels of dioxins depending on the origins or certain types of fish (e.g. blue whiting from the North Atlantic).
The Code of Practice for the Prevention and Reduction of Dioxin and Dioxin-like PCB Contamination in Food and Feeds (CAC/RCP 62-2006) provides guidance on the occurrence, reduction and prevention of dioxin contamination.
The presence of chemicals in feed ingredients may also result from:
● the use of substances as pesticides: residues of pesticides may be present in feed ingredients as a result of their use on crops; non-intentional presence of pesticide residues in crops may result from the uptake of residues present as a result of treating a previous crop with pesticides or from spray-drift, volatilization and/or runoff;
● the intentional use of substances in feed: substances used as feed additives may be toxic for animals and/or humans above certain levels; in certain countries, maximum permitted levels are set in animal diets by official regulators (EU register of feed additives);
● the use of processing aids in biofuels or food manufacturing processes which may end up in by-products (e.g. antibiotics used to control microbiological contamination may concentrate in yeast cultures used for ethanol production and be sold as a dehydrated protein source and in distiller’s dried grains with solubles after their use in fermentation for ethanol production);
● the presence in former foodstuffs of food additives or contaminants (theobromine) which are not of concern for human health but may be for animal health/welfare;
● the presence of residues of veterinary medicinal products in feed from animal origin (whether approved or unapproved such as nitrofurans in shrimps, chloramphenicol in milk powder);
● deliberate adulteration of feed materials (e.g. incorporation of melamine in vegetable protein concentrates to increase the nitrogen level);
● packaging residues resulting from mechanical unwrapping of former foodstuffs.
An overview of the potential biological and chemical hazards in feed and their potential for transfer to animal products is presented in Table .2.
These are mostly bones and pieces of metal, plastic or glass. They are potentially harmful to animals as they can provoke severe animal health problems (e.g. gut injuries, sudden death). However, they are unlikely to transfer to and impair the safety of animal products. The origin of physical hazards is often their presence in the environment (pollution) or poorly designed or maintained facilities and equipment or improper employee practices. They may also originate from former foodstuffs whose packaging has not been effectively removed.
This list of hazards is indicative and must be adapted to the specific situation of any feed operator for their own risk assessment, taking into account hazard characterization, exposure assessment and risk characterization. This indeed depends in particular on the position of the operator in the chain (i.e. supplier of unprocessed feed, trader/transporter, manufacturer of feed ingredients, manufacturer of premixes and/or compound feed, farmer),
TABLE .2 Non-exhaustive List of Potential Biological and Chemical Hazards in Feed and Potential Transfer into Animal Products
Hazard Potential sources Animal product
Bacteria (e.g. Salmonella, Brucella, Listeria) Pasture, forages, animal meals, oilseed meals Eggs, poultry, milk and milk products
Endoparasites (e.g. echinococcus, toxoplasma, trichinella) Pasture, forages, compound feed Various tissues containing infective cysts
Prions Ruminant proteins Specified risk materials (e.g. nervous system tissues, distal ileum)
Radionucleides: 90Sr, 131I, 137Cs Pasture, forages, crops Milk, meat
Heavy metals (As, Cd, Pb, Hg, Ni, …) Sea plants, micro and macro minerals, soil, etc. Higher: fish, kidney, liver Lower: meat and milk
Mycotoxins (fusarium trycothecens, etc.) Grains, co-products from grain processing Milk (aflatoxin) (limited transfer for most other toxins)
Plant toxins (tremetone, alkaloids) Botanical impurities in forages and crops Milk, meat
Dioxins, PCBs Natural presence; environmental contamination; heat processes Fat (in milk, meat, egg yolk)
Organochlorine pesticides Environmental contamination Fat
Veterinary drugs, pesticides, processing aid residues Feed produced from treated animals/crops; use of antibiotics in fermentation processes Meat, milk, eggs
Adulterants (melamine, etc.) Deliberate adulteration of feed Milk, meat
the type of raw material used and its geographical origin, and the type of animal species of destination of the feed. Some of the above hazards may therefore not be relevant for all feed operators, whereas some hazards not listed above may have to be taken into account. Additional source of information for hazard identification may be the Rapid Alert System for Food and Feed established in the EU to ensure rapid information and coordination of risk management in case of contamination. Figures .4 and .5 provide an illustration of the number of feed-related notifications to the RASFF in 2011. The absolute figures shall be handled with care as there is still a lack of harmonization in the procedures used by national authorities to notify contamination cases to the RASFF but the scenarios attached to them are more interesting to guide the hazard management at the level of operators.
FIGURE .4 Notifications of feed safety contamination to the RASFF in 2011 by type of feed in the EU.
Notification in 2011 by type of contaminant
FIGURE .5 Notifications of feed safety contamination to the RASFF in 2011 by type of contaminant in the EU.
A number of factors may also turn a negligible hazard into relevant risk because of an increase of its prevalence or the emergence of new hazards. The development of new processing methods for crops (e.g. biofuels production) generating new co-products involves using new processing aids with potentially harmful residues. Global warming may also imply a change in the geographic presence of, e.g., fusarium.
GOOD HYGIENE PRACTICES IN THE FEED SECTOR
The proper management of feed safety lies in the identification and implementation of good practices. The tools developed for the management of food safety such as ISO 22000, FSSC 22000, or PAS220 can also be used for the management of feed safety. A number of tools exist to help operators implement the hygienic practices that are relevant to their activities, namely:
● Codex Code of Good Animal Feeding (2004): this document establishes basic principles for the management of feed safety as well as minimum good practices for animal feeding at any step of the feed chain from feed ingredients producers to distribution to animals. It addresses human health risk only.
● IFIF/FAO Manual for Industrial Feed (2009): this document provides practical guidance on how to implement the Codex Code of Practice by commercial compound feed manufacturers and farmers producing feed on their farms. It addresses human health risk.
● PAS222 (2011): the prerequisite program for food safety in the manufacturing of food and feed was developed by the British Standards Institute for any operator of the feed chain and addresses hazards that may adversely affect both animal and human health.
In addition to these tools, a number of professional standards were developed at national/regional level and by specific sectors of the feed chain to meet the requirements relevant to their activities and to their national legal requirements. In particular, EU Regulation (EC) No. 183/2005 on Feed Hygiene encourages organizations of the feed chain to develop such sectoral guides to good hygiene practice and foresees an assessment of the relevance of such guides by authorities. These tools qualify either as codes/guides to good practice or as feed safety management systems and may be linked to a certification scheme. EU schemes are used to integrate animal health and even animal performance in their scope. A non-exhaustive list of such schemes is provided in Table .3.
Feed Safety Management Principles
All the above mentioned codes/guides are based on three essential principles:
- Responsibility of each operator for the safety of the feed it places on the market or uses. This principle supposes:
a. The implementation of a feed safety management system including a hazard analysis
(HACCP recommended or imposed);
b. The commitment of all staff from CEO to the operational management to the implementation of the feed safety management system;
gOOD HYgIENE PRACTICES IN THE FEED SECTOR
c. A definition of the scope of the good practice (human health/animal health, type of feed, production sites, type of operations, definition of terms) and establishment of feed safety objectives;
d. An audit of the performance of the feed safety management system;
e. A review of the feed safety management system at defined intervals in particular when major or significant changes to plant or products occur, to ensure its suitability and effectiveness of changes and improvements;
f. Proper internal communication flow and adequate training/qualification of all staff members.
- Traceability of products one step back/one step forward. This principle supposes:
a. A system of documentation to ensure traceability, which identifies (1) suppliers and intermediaries of purchased materials, and (2) to whom these incoming feeds have been supplied once processed into finished feeds;
b. Records of the details of all suppliers/intermediaries of purchased feed and batch numbers of all purchased batches as well as the nature and quantity of outgoing feed with their manufacturing date and the name and address of the customer to whom each batch is delivered;
c. Keeping records in such a way as to be easily accessible and allowing prompt identification of potentially contaminated products in case of incident and, if needed, withdrawal/recall of contaminated products further to a risk analysis.
- Cooperation along the chain to ensure a proper handling of the risk (e.g. instructions for use on labels) and with public authorities in case of contamination. This principle supposes:
a. Proper information regarding the nature of the product and its intended use: this should include in particular the following elements as appropriate:
− For all feed: a clear denomination of the feed in a manner that should not mislead the user of the feed as to its real nature, the identity of the supplier and the lot identification;
− In addition for feed additives, premixes and compound feed: the manufacturing date, the shelf-life and instructions for safe handling and use;
− In addition for compound feed and premixes: information about the species or category of animals for which the feed is intended; the purpose for which the feed is intended; a list of feed ingredients, including additives.
In principle, national legislation establishes such labeling requirements.
b. An external communication policy towards customers so that, in case of nonconformity of a safety nature affecting feed and triggering product withdrawal/recall, the feed supplier effectively, accurately and in a transparent way informs users of the feed at stake of the reason for its withdrawal/recall;
c. A communication policy towards authorities whereby operators, when deemed necessary, inform competent authorities if they consider that a feed or feed ingredient does not satisfy the feed safety requirements and statutory standards. The information should be as detailed as possible and should at least contain a description of the nature of the problem, a description of the feed or feed ingredients, the species for which it is intended, the lot identifier, the name of the manufacturer and the place of origin.
A number of basic principles shall be applied to assist in controlling feed hazards and address in particular:
● The location of the site and the surroundings;
● Processes and workspaces;
● Supply of air, water, energy and light;
● Waste management;
● Equipment suitability, cleaning and maintenance;
● Management of ingredients;
● Prevention and management of contamination/carry-over;
● Pest control;
● Management of internal/external returns; ● Product withdrawal procedures.
Below are some elements of these prerequisite programs which are extremely relevant for the management of feed safety.
Management of Ingredients
● Incoming products must be delivered by suppliers assessed on a regular basis by the purchaser (and prior to any delivery, in the case of a new supplier) or participating in a feed safety assurance system, subject to certification by a third party, and recognized by the purchaser. The purpose of the supplier assessment is in particular to check that there is an effective feed safety control system in place and to appraise the outcome of the monitoring program implemented by the supplier.
● Each batch of incoming ingredient shall be visually inspected. Documentation shall be checked to verify the integrity of the material.
● Ingredients should be stored separately from each other and from finished products.
● Procedures should be established to keep to a minimum the proportion of out-of-date stocks (e.g. first-in-first-out principle) by applying a careful stock rotation. Materials must be stored in such a way that they are clearly identifiable, and that their intake identification is easily visible.
Prevention and Management of Carry-over
● Contamination may arise from traces of products of a previous run that cannot be completely cleaned from the product line due to technical limitation: this type of contamination is called carry-over. Controlling carry-over is essential in particular in multispecies compound feed and premix plants handling substances prohibited or subject to restrictions of use for certain animal species (veterinary medicinal substances, feed additives or feed ingredients).
● Several factors may influence the level of carry-over of a substance in a feed mill: the facilities themselves (the equipment of the facilities), the substance itself, the feed matrix and the measures that are taken to control carry-over.
● Feed operators shall in the first place measure their level of carry-over in order to identify and apply the adequate measures, taking into account the statutory standards regarding carry-over.
● Feed operators producing feed for several species must draw up production schedules derived from the HACCP study taking into account the premise-bound carry-over, the
gOOD HYgIENE PRACTICES IN THE FEED SECTOR
characteristics of the substances (depending on adhesive strength, electrostatic properties and the size and density of the particles) and the species for which they are authorized. This may include scheduling exclusions.
● In order to establish this schedule, the company must define for each substance regarded as at-risk further to the HACCP study the number of batches to be produced between a batch containing a given active substance (additive including coccidiostats and histomonostats or veterinary medicinal substances) and a batch for a non-target species or for withdrawal feed or for continuous food-producing animals (dairy cows, laying hens). This number of batches will be defined for each animal species, taking into account the level of carry-over of the plant, the physical characteristics of the substance and the level of risk for animal and public health.
● Where necessary, the equipment must be flushed to avoid carry-over between batches. Flushing must be done using a specified amount of wheat feed or other suitable material, proven to purge the system adequately.
Management of Internal/External Returns
● The production of finished feed must be organized, both on an internal and external level, with an eye to limit possible returns to a minimum.
● External returns (from customers) should be avoided. When occuring, they must be assessed and, if needed, placed in separate adequately segregated storage to prevent contamination of other feed.
● Internal returns, other than flushing or cleaning material, must, whenever possible, be reincorporated into their original batch or “run.”
● Procedural rules must lay down in which feed formulation returns may be incorporated and the maximum percentage of returns in the respective feed type. In no case should a product containing an ingredient subject to restrictions of use be reprocessed into a batch designed for a species for which this material is prohibited.
More elements regarding prerequisite programs in the feed sector can be found in the standards listed in Table .3, in particular as regards transport, storage, etc.
Hazard Analysis and Monitoring Plans
The prerequisite programs shall be completed by a hazard analysis specific to the situation of the individual company. The Codex Code of Practice for Animal Feeding specifies that, where applicable, HACCP principles should be followed. HACCP in its full extent requires expertise and resources that are not always available, in particular to small operators, especially small farms.
A number of publications provide guidance on how to perform HACCP. The Codex guidelines remain the internationally accepted reference (ftp://ftp.fao.org/codex/Publications/ Booklets/Hygiene/FoodHygiene_2003e.pdf). Although there are currently no such Codex guidelines for feed, the approach for food is applicable to feed, while taking into account the specificities of the feed sector as specified above, i.e.:
● The number of operators, in particular the number of operators whose core business is not feed but food or non-feed/food industry (e.g. biofuels); some of these operators do not even know that their by-products are used in the feed sector and some even refuse to be regarded as feed operators for image purposes;
TABLE .3 Type, Origin and Scope of Feed Safety Management Documents
Name area Type of tool
SFSF x x x x USA USA Certifiable scheme
EFMC x x EU EU Code
GMP+ International x x x x x NL Global Certifiable scheme
QS x x x x x DE DE Certifiable scheme
FEMAS x x UK Global Certifiable scheme
UFAS x x UK UK Certifiable scheme
OQUALIM x x FR FR Certifiable scheme
OVOCOM x x x x x BE BE Certifiable scheme
EFISC x EU EU Certifiable scheme
GTP x EU Global Certifiable scheme
FAMI-QS x EU Global Certifiable scheme
Feed & Food Safety x x x x BR BR Certifiable scheme
GLOBAL G.A.P. x x Global Global Certifiable scheme
FM: Feed material; FA: Feed additives; PR: Premixes; CF: Compound feed; TR: Trade
● The type of risk addressed, i.e. first the combination of human health, animal health/ welfare, and, in certain cases, animal performance;
● The specificity of the human health risk assessment involving the biological interference of the animal;
● The number of animal species involved, with different sensitivity to hazards; ● The number of feed ingredients.
The feed safety standards listed in Table .3 may also provide guidance on how to perform HACCP in the feed sector. The new Codex Task Force on animal feed is currently developing specific risk assessment guidance for national governments on feed safety impacts on food safety using the present food HACCP guidance as reference.
A number of tools are available to operators to carry out their hazard analysis and help set monitoring plans and establish critical limits:
● The national statutory standards: national legislation may establish maximum limits for contaminants in feed ingredients and/or compound feed: in the EU, Directive 2002/32/ EC establishes maximum limits for chemical contaminants such as heavy metals, mycotoxins, certain pesticides, dioxins, etc. based on human health, animal health and animal performance as well as on the ALARA (As Low As Reasonably Achievable) principle; likewise, MRLs may be established in national legislation for pesticides and/or veterinary medicinal products in feed ingredients of vegetable or animal origin;
ExAMPLES OF FEED SAFETY INCIDENTS AND WHAT LESSONS CAN BE LEARNED
● The Codex standards: in case of absence of national standards, Codex MRLs for pesticides in unprocessed plant products is the reference for feed business operators
(Codex Pesticides Residues in Food Online Database);
● Results of monitoring programs: certain national authorities are used to publish the outcome of their monitoring programs on certain contaminants. Certain food safety authorities such as EFSA may also publish reports on the occurrence of contaminants in food and feed, e.g. for Salmonella;
● Rapid alert systems, e.g. the RASFF.
From Good Practices to Certified Feed Safety Assurance Schemes
Assessment of suppliers is an essential element for feed safety risk management. Third party certification of compliance with good practices enables reduction of the number of audits while preserving know-how.
A number of bodies having developed codes of good practices established also a third party certification scheme (see Table .3). Such schemes cover either part of the chain or embrace the feed chain as a whole, and may also be integrated in broader schemes covering the whole feed and food chain. Alternatively, they may be also cross-references with downstream assurance schemes run by the livestock industry or retailers such as GlobalGAP. In certain countries such as the UK, Belgium or the Netherlands, certification against the national feed safety assurance scheme is a prerequisite to market access.
Several Feed Safety Assurance Schemes such as GMP+ International, OVOCOM or QS have also established collective monitoring programs. This allows reduction of the need for analytical checks while improving the knowledge on the occurrence of contaminants.
EXAMPLES OF FEED SAFETY INCIDENTS AND
WHAT LESSONS CAN BE LEARNED MPA in Glucose Syrup in 2002
Medroxyprogesterone acetate (MPA) is a synthetic hormone having progestogen activity and is used in human and veterinary medicine. It is no longer permitted for use as growth promoters in the EU.
Fertility problems occurred in three pig farms in the Netherlands on 20 May 2002. Animals were fed with wet feed containing a high concentration of contaminated glucose syrup sourced directly by farmers from a Belgian company, which happened also to be a waste processor. The first step of the investigation carried out by Dutch authorities as regards the origin of the contamination was completed on 20 June 2002 and notified to the EU Commission and other member states through the Rapid Alert System Food and Feed. Further investigations enabled the identification of two other contamination tracks. The whole tracking and tracing operation was completed on 24 July 2002.
The MPA contamination found its origin in Ireland in the illegal mixture of pharmaceutical non-hazardous waste with hazardous waste containing MPA at some point in the waste disposal chain. From September 2000 to June 2002, 1850 kg of MPA was illegally classified as non-hazardous waste and shipped without notification to the Belgian waste processor. This company then mixed up the waste with glucose syrup.
The contaminated syrup was first sold to soft drink producers up until December 2001. Then, the Belgian company supplied its glucose syrup to (1) wet feed companies which resold the product directly to home mixers and to a compound feed manufacturer who mixed up the glucose syrup with molasses, the mixture then being included in compound feed distributed to farmers and (2) a molasses trader who mixed up the glucose syrup with molasses, the mixture being sold to feed manufacturers for inclusion in compound feed. As a consequence, the spread of the contamination involved a large number of feed business operators in the Netherlands and Belgium and almost half of the Dutch livestock farms were subject to temporary blockage.
A product recall for contaminated glucose syrup, molasses and feed was undertaken according to a procedure approved by the EU authorities in Belgium, Germany and the Netherlands, and, to a lesser extent, in other member states. Pig market prices fell in midJuly 2002. The cost of the MPA contamination was estimated between EUR 107 and 132 million.
What did not Work?
● The main shortcoming in this incident was that there was no clear physical separation between the hazardous waste stream and the feed chain.
● Although the Dutch feed/food chain has developed a comprehensive risk managementoriented quality assurance system (GMP+) subject to external audits and imposing the sourcing of feed materials from GMP+-approved suppliers only, the Belgian waste processor, which did not handle a Dutch GMP+ approval, managed to sell its products to GMP+-approved home mixers and a molasses trader.
Lessons to be Learned
● As a matter of principle, the waste management streams should be kept physically separated from the feed chain.
● Any introduction of a new material or modification of the composition of a material or change in the manufacturing process should be subject to a hazard analysis by the supplier.
● Suppliers who are not audited by a third party for their feed safety risk management should make available to their customers the results of their own hazard assessment.
● Audits systems from certified Feed Safety Assurance Schemes should be more efficient in the detection of non-compliances.
Contamination of Bread Meal with Dioxins in Ireland in 2008
The dioxin contamination incident originated in the detection of elevated levels of PCBs in a pork fat sample, and feed analyzed on a pig farm was also positive for PCBs. The contaminated feed was traced back to a company specialized in the processing of bread crumb not used for human consumption. Samples of fats and feed taken in other pig farms that
ExAMPLES OF FEED SAFETY INCIDENTS AND WHAT LESSONS CAN BE LEARNED
were identified as having received similar feed from this company also proved positive. Considering that those 10 farms represented more than 10% of the Irish pig slaughters, the Irish government ordered a full recall of pork and pork products manufactured from all pigs slaughtered in Ireland within the last 3 months before the identification of the contamination. This decision was due to the traceability system in place in the pork chain but was not sufficient to allow for a targeted recall, considering the high degree of commingling of product in secondary processing.
All of the evidence available suggested that the incident occurred as a result of contaminated fuel being used in an oil-fired burner (direct flame drying system) that generated the heat to dry the feed at the bread crumb recovery operation. Laboratory tests showed that the oil used as a fuel in the burner at the plant was contaminated with PCBs.
What did not Work?
● The feed business processing the bread crumb should have identified the risks associated with the direct drying process in its feed safety management system based on HACCP principles.
● The authorities failed to verify that the feed business was complying with the legislation in that the HACCP plan was not fit for purpose, and the inspection of the premises was inadequate. The company was classified as “low risk” by the authorities simply because it was not using animal by-products with no consideration of direct drying as a “highrisk” process.
Lessons to be Learned
● Direct drying should be regarded as a high-risk operation.
● There is a need to ensure that any feed operation is placed under the supervision of the feed safety authorities.
Dioxins in Feed Fats in Germany in 2010/2011
On 21 December 2010 a feed mill located in Niedersachsen detected contamination of compound feed for laying hens with dioxins above the maximum permitted levels as part of its own checks.
The German authorities having been informed by the company started investigations and discovered that a fat processor located in Schleswig-Holstein had purchased several consignments of fatty acids for the purpose of producing fat. This fat processor produced both feed fat and fat for industrial uses in separate lines. However, the processor subcontracted the production of feed fat containing the fatty acids to another fat processor located in Niedersachsen.
The fatty acids had been purchased from a biodiesel plant, from which the material was delivered directly to the fat processor in Niedersachsen, via a Dutch trader that handled both fat for the production of feed and fat for industrial uses. The fat processor in Niedersachsen subsequently used these fatty acids for the production of feed fat that was directly dispatched to several manufacturers of compound feed as feed fats.
The mixed fatty acids were confirmed to be contaminated by dioxins above the EU maximum permitted levels. The likely source of the contamination was the use of contaminated raw materials or technical processing aids for the production of biodiesel, which through the process were concentrated in the fatty acids.
Investigations from the authorities at the level of the two fat producers in SchleswigHolstein and Niedersachsen led to the identification of eight deliveries of potentially contaminated fatty acids representing a volume of 206 t. These 206 t where mixed up with other fat products and sold as feed fats (2256 t) to 25 compound feed manufacturers. The compound feed was then delivered to almost 4500 farms that were subsequently blocked. Most compound feed was already used at the time of the blocking of the farms. Random testing of the samples of compound feed kept by the manufacturers showed levels of contamination below the maximum permitted for compound, which is logical given the low inclusion rates of feed fats in compound feed and the contamination load of the feed fats. Farms were unblocked based on a risk assessment including estimation of the theoretical highest contamination level of compound feed; further analysis was then performed. Only a few farms have shown results on eggs and pig lard above the maximum permitted levels for animal products.
The fat processor in Schleswig-Holstein benefited from a good reputation and was GMP+ and QS certified; feed companies believed that this certificate also covered the activities of the Nierdersachsen plant.
What did not Work?
● The mixed fatty acids were identified in the contract between the biodiesel producers and the Dutch trader as “Mixed fatty acids from cooking oils – not intended for food or feed purposes.” But in the contract between the Dutch trader and the fat processor in SchleswigHolstein, the fatty acids were identified as “Technical mixed fatty acids.” As a matter of principle, there was no legal requirement in the EU prohibiting the use of technical fatty acids in the production of feed providing they meet all feed safety criteria and unless it is explicitly mentioned that these are not to be used for this purpose, which was the case for the contract between the biodiesel plant and the feed fat company from Niedersachsen.
● The fat processor in Niedersachsen was not registered by public authorities as a producer of feed fat, only as a transporter of feed.
Lessons to be Learned
● Traceability procedures when well implemented allow the quick identification of potentially contaminated batches of fatty acids and the farms that received compound feed containing the feed fats produced with the contaminated fatty acids.
● There is a need to secure the identity of the products along the chain and in particular their suitability/non-suitability for feed use.
● Confidence in suppliers should not replace regular checks and audits.
● A proper risk assessment is required at all stages of the chain.
● Traders shall feel responsible for the safety of the products they place on the market.
● Although monitoring by users of feed materials enabled the detection of the contamination in this case, the detection at the level of the supplier is by far the most effective way to detect contaminations at an early stage and prevent their propagation (“top of the pyramid” principle).
Feed safety management is particularly complex in that it involves a larger area in terms of type of risk (human health, animal health and welfare and even livestock performance), type of assessment (direct impact on animal but also transfer/biotransformation from feed to products of animal origin) and the variety of animal species concerned. The involvement of all operators in the chain is essential to ensure cost-effective feed safety management. Contaminations should be identified at the earliest stage possible, taking into account the structure of the feed chain and the rapid turnover at premixes and compound feed mills. To this end, it is essential that operators are made aware that (part of) their product is destined for use in feed. Leaving the responsibility to control feed safety to the last stages of the chain is not only costly but also inefficient. Collaboration among all operators in the chain is therefore essential and the safety management tools developed at different levels of the chain have contributed to a significant improvement in the management of feed safety over the past years.
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AIC (Agricultural Industries Confederation). Universal Feed Assurance Scheme (UFAS) – Feed Materials Assurance Scheme (FEMAS). UK. .
BSI (2011) PAS 222:2011 – Prerequisite programmes for food safety in the manufacture of food and feed for animals.
COCERAL. European Code of Good Trading Practices (GTP). Europe. www.gtpcode.eu.
Codex Alimentarius., 2004 Code of Practice on Good Animal Feeding. .
EFIP., European code on good practice for the industrial manufacturing of safe feed materials (EFISC). Europe. www.efisc.eu.
FAO and IFIF., 2010. Good practices for the feed industry – Implementing the Codex Alimentarius Code of Practice on Good Animal Feeding. FAO Animal Production and Health Manual No. 9. Rome. .
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OQUALIM., Guide de Bonnes Pratiques de la Fabrication des Aliments Composés pour Animaux. France. .
OVOCOM (Consultation Platform for the Animal Feed Chain). Good Manufacturing Practice – GMP. Belgium. www.ovocom.be.
QS. Leitfaden für die Futtermittelwirtschaft. Germany. www.q-s.de/dc_feed_sector.html.
Sindiraçoes – Feed and Food Safety Program. Brazil. www.sindiracoes.org.br/programa-feed-food/o-programa.