The European Rapid Alert System for Food and Feed (RASFF) is a central information platform for the national authorities of all EU Member States on current risks in the food and feed sector. We have been RASFF contact point for feed (Vienna) since 2002 and national contact point for food (Salzburg) since 2007.
The individual notifications on food and feed can be accessed in anonymous form on the publicly accessible RASFF portal of the European Commission. The aim is to provide information on the most important and current risks in the feed sector in the EU area.
Recommendations for the control of Salmonella in feed production.
After Salmonella Agona was frequently found in imported soybean meal in 2011/2012, the feed industry decided in cooperation with us to draw up recommendations for self-monitoring of Salmonella contamination in feed. The working group was composed of representatives of the compound feed industry, oil mills, feed wholesalers and AGES. The aim was to develop practicable guidelines to enable self-monitoring and a coordinated approach within the industry in the event of salmonella occurrence. At the same time, however, a better awareness with regard to hygiene and a proactive approach to problem solving are to be promoted. Four risk levels were developed for the three defined types of operations: oil mills, wholesale trade and compound feed production, suggesting different approaches:
- Level 1: routine operations
- Stage 2: sporadic occurrence of salmonella in feedstuffs
- Level 3: frequent detection of Salmonella in feedstuffs
- Level 4: human illness proven to be linked to a contaminated feed.
The measures recommended for each level can be found in detail in the recommendations for the control of Salmonella in feed production (see downloads at the bottom of the page).
Salmonella in dust
Protein-containing straight feedstuffs such as soybean, rapeseed or sunflower extraction meal are considered a significant source of contamination for compound feed and in compound feed operations. In this context, salmonellae often occur in feed at very low concentrations. However, low bacterial levels make analytical detection of positive samples difficult. Dust particles, on the other hand, represent an excellent medium for Salmonella due to their large surface area and can be detected here more readily than in (mixed) feed.
Against this background, the SINS project was designed to provide an overview of the contamination rate in Austrian feed businesses (individual or compound feed). For this purpose, 3699 dust samples were taken and examined along the entire production process in 39 feed plants. In addition, an overview of the hygiene status with regard to salmonella was drawn up - based on a period of one year.
Salmonella were detected significantly more frequently in the area of raw material storage, especially in protein-containing straight feeds (extraction meal), as well as around the elevators and in the area around thermal treatment, than after thermal treatment.
During the observation period, Salmonella was detected more frequently in dust samples than in straight feeds. However, the results obtained in the dust samples showed a clear correlation with the serotypes detected in the feeds.
In addition, oilseed crops were found to be a significant contributor to the introduction of Salmonella into the compound feedlot. Salmonella introduced into a feed mill can become persistent and (re)contaminate subsequent batches of compound feed, depending on the serovar and local conditions at the facility.
The seasonal fluctuations in the occurrence of Salmonella were particularly striking. Here, an increased occurrence was particularly evident in the cold season. Especially in the pelleting process, the ratio of outside temperature to pelleting temperature - with regard to possible condensation - seems to be the decisive factor.
Further information on this project can be found here.
Decontamination with organic acids
Salmonella in feed can cause enormous economic damage in the affected compound feed businesses and farms. The decontamination of salmonella in feed as well as the reuse of these decontaminated feeds is permitted under feed law.
With the introduction of a new additive functional group "(n)" for hygiene improvement, a legal basis was created at EU level via Regulation (EU) 2015/2294. Hygiene improvers are substances or microorganisms that have a beneficial effect on the hygienic properties of feed by reducing specific microbiological contamination.
The use of formaldehyde to decontaminate feed is no longer permitted.
Decontamination of feed can be done either by physical or chemical means. Physical decontamination can be done either by heat or also by irradiation (mostly dog toys).
Chemical decontamination is done by mixing organic acids and their salts or mixtures thereof into the contaminated feed. However, the effect advertised by the acid producers is often not achieved in practice with the recommended exposure times and admixture rates for the acid preparations. Examples of organic acids for decontamination are: Formic acid, lactic acid, propionic acid and benzoic acid and their salts. In most cases, mixed preparations are offered.
The success of a decontamination must always be proven by a certificate of analysis. To exclude false negative results, it is advisable to carry out the tests using a tenfold preparation. Inadequately performed decontamination of feedstuffs leads to further contamination of other feedstuffs (cross-contamination) and subsequently to infection in the poultry flock and thus to a risk of infection for humans through the consumption of animal foodstuffs (egg and meat). Due to insufficient decontamination efficacy, Salmonella outbreaks have occurred repeatedly in poultry farms in the past.
Decontamination study - DECONTAM
The DECONTAM study was conducted by our Institute of Animal Nutrition and Feed between 1.7.2014 and 30.6.2016. The main objective of the study was to find out at what acid level and contact time reliable decontamination can be achieved in selected test feeds.
The study was conducted with three Salmonella contaminated feeds (soybean extraction meal, ground milk thistle seeds and corn gluten). Furthermore, five acid preparations were used for the study. The recommended dosage of the manufacturers or distributors was between 0.1 - 1 % for the four liquid preparations and 0.3 - 1.3 % for the powder preparation. Three different exposure times (1, 2 and 7 days) and seven concentrations (1 %, 2 %, 3 %, 4 %, 5 % ,6 % and 7 %) were tested with the five acid preparations and the three feeds.
Each test variant was analyzed with a tenfold approach. In the study, successful decontamination is understood to mean that Salmonella is no longer detectable (0/10) in the previously highly contaminated feed (10/10) after acid treatment and with a specific exposure time in a tenfold batch.
At low acid concentrations, as recommended by the manufacturers in the product data sheets, no significant decontamination occurred in any of the three feeds. A reliable effect occurred even with the more effective liquid preparations only with 6% acid addition at 7-day exposure time or 7% acid addition at 1-day exposure time. The powder preparation used did not provide satisfactory decontamination in any of the three test feeds.
The use of acid preparations for the decontamination of Salmonella in compound feeds, but especially for finished feeds, cannot be recommended in compound feed production and for the farm. Due to the high amount of acid required, this may result in feed refusal and severe irritation of the animals' digestive tract. In addition, interactions with other feed components, such as calcium carbonate or other minerals, may occur.
Based on our DECONTAM study results, decontamination of Salmonella with the five acid preparations used can only be recommended for raw materials (straight feed) and only at doses of 7% acid addition with a one-day contact time or 6% acid addition and a seven-day contact time.
Further information on the DECONTAM study can be found here.
Mycotoxins (mold toxins) and grain corn
Grain corn represents an integral feed ration component in livestock feeding, especially in pig finishing operations. Likewise, grain maize is significantly used as wet and dry maize in the starch industry and in citric acid production. In these utilization directions, the remaining protein component is marketed as high-quality feed. For each utilization direction, it is important that the harvested crop is as qualitatively flawless as possible. Cob rot caused by Fusarium fungi poses a quality risk. Its occurrence can be reduced by cultivation measures, in particular the choice of variety, but is highly dependent on the annual weather conditions.
Mycotoxin pre-harvest monitoring of grain corn Mycotoxin levels (mold toxin levels) have an influence on the possible uses of corn and corn products. In order to get a first overview of the quality of the corn harvest before the main harvest, the Austrian Chambers of Agriculture and we carry out mycotoxin pre-harvest monitoring of grain corn. The latest data on mycotoxin monitoring can be found here.
The year 2020 was characterized by high precipitation in September and October. The load of deoxynivalenol (DON) with an annual median of 1097 µg/kg and an annual mean of 1618 µg/kg was therefore higher in this year than in previous years, as expected. In the Illyrian climate region there were isolated hail events in 2020, which can lead to higher loads of Fusarium and thus to an increased occurrence of mycotoxins. Median DON values represented the highest median values in each growing region over the past five years, with the exception of the median value in the Northern Alpine Wetland in 2016 (887 µg/kg). The 2020 DON results represent the second highest values since the monitoring program began, with higher values recorded only in 2014. Based on the levels in the samples from the variety trials, increased caution is warranted with regard to the quality and intended use of the Illyrian corn crop.
Within the DaFNE project "Optimization of a reliable methodology for the evaluation of genetic determinacy and differentiation of susceptibility to cob fusariosis in the maize assortment in Austria" (acronym: KOFUMA, project no. 100792), investigations of the mycotoxin content in the grain maize variety value test were carried out in 2011 - 2014. These were continued as part of the monitoring program for mycotoxins in grain maize. Here you can find all results of the mycotoxin monitoring of the past years.
Mycotoxins - Feed law situation
Mycotoxins belong to the group of undesirable substances, whereby the associated legal text (Directive 2002/32/EC) only specifies a limit value for the mycotoxin aflatoxin B1. Other mycotoxins, such as deoxynivalenol (DON), zearalenone (ZEA), but also ochratoxin or fumonisins are regulated in the EU recommendation 2006/576/EC with guide values. Currently, maximum levels are being discussed at the European level instead of guideline values for compound feed. Only for straight feeding stuffs there shall be guideline values in the future. Furthermore, the accepted values for mycotoxins in feedstuffs are to be adjusted downwards.
If a limit value is exceeded, the product concerned must be removed from the feed chain and may not be diluted. Exceeding the guideline value, on the other hand, can be countered by dilution. In addition to dilution with uncontaminated or less contaminated corn, the use of other types of grain (wheat, barley) is also recommended. The following is an excerpt of the guideline values for the mycotoxins deoxynivalenol (DON) and zearalenone (ZEA) according to the above-mentioned EU recommendation:
|DON (µg/kg with 88 %T)
|ZEA (µg/kg with 88 %T)
|Cereal and cereal by-products
|Compound feed for piglets and gilts
|Compound feed for sows and fattening pigs
When using so-called mycotoxin binders, care must be taken to ensure that only products approved for "reducing contamination with mycotoxins" may be used. Details on dosage and conditions of use can be found in the relevant approval regulations.
Other products advertised as mycotoxin binders - contrary to feed law requirements - belong in the majority to the category of technological feed additives and may not be advertised or used for other purposes. In addition, it should be noted that these may not be suitable for binding the desired mycotoxins due to a wide variety of chemical properties.
Ethoxyquin in feed
Ethoxyquin is a chemical compound that has antioxidant properties. That is, it prevents the rancidity of fats and delays the degradation of vitamins such as vitamin A, vitamin E, carotenoids, etc. Ethoxyquin has been used as an antioxidant in animal feed since the 1950s. As a technological additive, it was included in the feed additive register with the identification number E 324 and was permitted with a maximum value of 150 mg/kg complete feed for all animal species, with the exception of dogs (100 mg/kg).
Due to the unclear data on the toxicity of ethoxyquin, its approval as a feed additive was suspended as of June 28, 2017.
Feed containing certain additive preparations of fat-soluble vitamins and related products and ethoxyquin may no longer be used as of Dec. 31, 2018. All other feeds containing the additive ethoxyquin may no longer be used since March 28, 2018.
Feed containing feed materials such as dry algae, fish, other aquatic animals and products derived from them may contain ethoxyquin and were still allowed to be used until June 30, 2020.
According to the new additive regulation, an application for authorization had to be submitted for the additive within seven years and all relevant authorization documents had to be submitted. Due to the unclear data situation regarding the toxicity of ethoxyquin, a safety assessment by the European Food Safety Authority (EFSA) in October 2015 could not confirm the safety of the additive.
For an intermediate of ethoxyquin, ethoxyquinonimine, not enough data could be provided regarding genotoxicity (possible damage to the genetic material). Furthermore, contamination with another intermediate from the manufacturing process (p-phenetidine) is considered a possible mutagen. A mutagen causes a permanent change in the genetic material.
The data situation is also insufficient with regard to the actual hazard potential for humans and the occurrence of intermediates. Ethoxyquin is preferentially deposited in fatty tissue. Excessive consumption of (fatty) fish in which ethoxyquin has accumulated in fatty tissue could pose a potential hazard to humans.
Ethoxyquin is currently being replaced by other antioxidants, such as butylated hydroxyanisole (BHA, E 320) and butylated hydroxytoluene (BHT, E 321). The presence of ethoxyquin in feed is checked and monitored by the competent authorities in the European Union as part of feed controls.
What are antioxidants needed for?
Feed materials such as fish meal and fish oil have a high fatty acid content. These react with oxygen. In combination with higher temperatures, they can ignite or explode. During transport, e.g. on container ships, antioxidants are therefore used to prevent possible explosions.
Ethoxyquin has also been used in other products used in animal feed production that contain fat-soluble vitamins. Until the end of its approval as a plant protection product in 2011, ethoxyquin was also used to protect against skin rot in pears in glasshouses.
Last updated: 10.10.2023