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S. L. Woodgate
EFPRA

The feed ban instituted within the EU for animal proteins produced and used in the EU (or exported out of the EU), has now been in operation for over seven years. The ban was enacted to achieve one specific objective; to prevent ruminant species consuming ruminant proteins. However, while BSE epidemics in all EU countries have now been bought under control and the number of new cases of BSE have fallen by over 40% per year over the last 10 years, the feed ban remains.

What can be done now to lift the feed ban? The question normally posed regarding “what are the criteria needed to be able to lift the feed ban?” is answered by reference to the need for ‘control’ tools. In one sense, several of the control tools indicated by the regulators are already in existence. Primarily, document controls are already used in the process chain from animal to slaughter to the production of C3 by-products their processing and the dispatch of processed products. Secondly, the marking of Category 1 and 2 by-products and the products derived from them has recently been approved after a rigorous and practical series of validation tests.

In essence this leaves the third and final question about control tools. Is there yet a validated test to identify the species of origin of a PAP? In itself, this is an interesting question, as it does not fully explore the scope and intent of the feed ban, but rather poses two further questions.  Firstly, if the feed ban is actually only a ban of ruminant proteins in feedstuff, what level of ruminant protein is acceptable as a contamination level in feed, in order to result in the continuation of BSE eradication programme? Secondly, what would be an acceptable level of cross contamination of ruminant protein in non-ruminant PAP’s destined for use in mono-gastric feeds?

The former question has been resolved, in one sense, by the ability of microscopy to detect 0.1% terrestrial proteins in animal feeds. Thereafter other detection technologies would be expected to be validated to at least this level. The latter question has not yet been resolved satisfactorily by the regulators and is now the main focus of EFPRA in their attempt to achieve the re-entry of certain PAP’s into mono-gastric animal feed.

To provide a scientific and independent platform for a risk based assessment by EU regulators, EFPRA commissioned a report from DNV in 2006 1. In summary, the risk assessment considered a number of scenarios in relation to two possible areas of cross contamination. Firstly, ruminant contamination of non-ruminant PAP. Secondly, the possibility of the non-ruminant PAP being used in ruminant feed. The results indicated very low levels of risk - in terms of the chance of increased cases of BSE in the European cattle herd - and also produced a lower “risk” than seen in an existing EFSA opinion2.  As a result, EFPRA therefore propose that a level of 1% contamination of non-ruminant PAP with ruminant PAP is acceptable as a practical threshold level, which does not increase the risk of additional TSE within ruminants.

With regard to this proposal, EFPRA and colleagues at CCL have conducted some preliminary evaluations, in two phases. Phase 1, screening of reference and commercial PAP’s for presence of species. Phase 2, spiking of control (non-ruminant PAP) with various levels of ruminant PAP. The detection methods studied included 3 PCR methods and a lateral flow immuno-stick method (Reveal MBM-feed). The results from phase 1, with reference PAP samples, using mainly PCR techniques, are described by Magry et al 3.
From a practical industry standpoint the conclusion drawn from these results is that current PCR techniques - for detecting a PAP of one species contaminated by PAP of another - are not fit for purpose.

In respect to phase 2, it appears that the Reveal (Ruminant MBM-feed) shows promise and could be used to screen non-ruminant PAP’s for the presence of ruminant PAP at a levels of 1% or higher ( Magry et al4). The results of the tests are summarised in Figure 1.  [Green indicates correct result, Red indicates not detected]

Fig 1 Summary results from Spiking tests: Ruminant PAP in non-ruminant PAP

EFPRA consider that incorporation of this test within a control tool programme, would enhance a risk based-control tool approach to allow the use of non-ruminant PAP in non-ruminant animal feeds.
There remains one area of concern, ie the ban on intra-species recycling, which the species identity tests are so far unable to resolve.

However and most importantly, this problem may be overcome by an EFPRA 5 proposal for terrestrial non-ruminant PAP to be approved for use in aquatic species feeds (Aqua-Feeds).  This proposal considers all of the above mentioned and available control tools incorporated into a holistic risk based approach through dedicated channels.

How do these ideas and proposals fit into the SAFEED- PAP project? It is important to recognise of course that there are no real conflicts, as controls for both feed and PAP are necessary. However, from a practical industry perspective it would be helpful to consider the aspects of PAP cross contamination with a higher level of priority than it currently receives. For the rendering process industry, PAP is the real means of utilisation that requires control. What is more, release of certain non-ruminant PAP’s from the feed ban,    will in principle, allow export of these PAP’s to 3rd countries. EFPRA therefore consider that PAP specific control tools are essential for harmonious international trade. Furthermore EFPRA propose that significant effort is expended to ensure international validation of any successfully validated EU PAP species methods. 

References:
1.  DNV (2006)  Report for EFPRA 22514037 final (04-08-2006)
2.  EFSA (2003)  Q-2003-099
3.  Margry et al (2007)  Poster at SAFEED-PAP conference Namur, November 2007
4.  Margry et al (2007)  CCL report RAP-1001353
5.  EFPRA (2007)  EF-07-085