Volume 5: Animal Health, 1989-96
3. Introduction of the animal SBO ban
Consideration of a statutory animal SBO ban
Contingency planning for an animal SBO ban
Agriculture Select Committee's inquiry into BSE
Pressure from the food industry
Experimental transmission of BSE to a pig: SEAC recommends an animal SBO ban

Contingency planning for an animal SBO ban

3.199 On 5 July 1990 Mr Maclean sent a note to Mr Gummer setting out a series of proposals on BSE. The note was copied to a number of MAFF officials, including Mr Capstick, Mr Meldrum, Mrs Attridge, Mr Lowson and Mr Lawrence. On a possible SBO ban for pigs and poultry, Mr Maclean referred to the experiment involving pigs, which was being undertaken in accordance with the recommendations in the Southwood Report:

As you know, we are now 14 months into our experiment of injecting large quantities of contaminated material into pigs' brains and so far they are all healthy. If, however, an encephalopathy does occur by this route, which an expert said is a billion times more sensitive than oral ingestion, we would have no option but to ban specified offals from pig and poultry feeds also. No-one should imagine that we could do anything else. It would be pie in the sky to believe that we could hold the line on this or somehow distinguish poultry feed from pig feed.

If this eventuality (unlikely though it is) should occur, we must be ready with an immediate offals ban for pigs and poultry and I want us to prepare for that now. We do not need to say anything publicly at this stage, merely to accept the principle of being prepared.

Pets are another issue. If it was proved that the specified offals were responsible for pet encephalopathy there would be an instant and irresistible demand for banning led by the PFMA. When we are in the human food safety business, I am not convinced that we should be involved in taking action over pet food which has no human safety implications. Admittedly the great British public and media would not see it that way but perhaps there is a half-way house - namely labelling. We could announce that pet owners as consumers have a right to know what is in their pet foods and we will insist on adequate labelling throughout Europe.

If we got labelling, we could avoid a banning scenario. ¹

3.200 In summary Mr Maclean set out key action required. This included:

7. Prepare for the possibility that we may in future have to ban offals in pig and poultry feeds. No immediate action required except to agree the principle and be ready to admit that if asked.

8. Prepare for the possibility of a problem with pet foods. Kick this into the EC forum by suggesting contents labelling throughout Europe. No immediate action required except agreement in principle and a willingness to admit this if pressed. ²

3.201 Mr Gummer's Private Secretary replied to Mr Maclean on the same day that 'the Minister feels that he could only take decisions on the proposals after having considered all their implications'. He asked that the Department urgently advise on the implications of the proposals. ³

3.202 On 9 July 1990 Mr Lawrence provided Mr Lowson with a 'hurriedly prepared' draft paper on the use of SBO in rations for pigs and poultry. ⁴ The paper was copied to Mr Meldrum and Mrs Attridge, among others. It specifically addressed the question of 'whether there is a need to take action to restrict or prohibit the use of by-products derived from bovine specified offals in pig and poultry rations and in the preparation in pet foods'. ⁵ The paper set out action the industry had taken and the perceived risk from specified offals to pigs, pets and poultry. It examined this question at some length and concluded:

In summary, there have been a number of developments which, put together, would indicate that the meat and bone meal derived from specified offal is unlikely to contain the BSE agent and if it does it would be at titre levels which would seem unlikely to provide a sufficient dose to create a risk of transmission, even if there was scientific evidence that such a risk existed.

In the circumstances, there would seem to be no justification for taking further measures to deal with specified offals. The scientific evidence does not point to the need for legislative action to proscribe the use of meat and bone meal derived from specified offal in pig and poultry rations and pet food. In practice however, the industry has adopted measures which largely ensures that this material is not fed to these species, even in the absence of any scientific evidence which points to the need to do so.

⁶

3.203 On 9 July 1990 Mr Lowson minuted Mr Andrews in response to Mr Maclean's note of 5 July 1990. He noted that he had agreed to deal with the topics of pithing rods, a ban on offals in pig and poultry feeds, and the implementation of Southwood's suggestion on animal feeds. On the latter two he said:

There is not much that we can do now to prepare for the possibility that offals (presumably specified offals) will need to be banned from pig and poultry feed. We would need to do so if evidence arose that these species could be infected with a spongiform encephalopathy by the feed route (i.e. not simply that pigs were susceptible to infection by artificial means), and if asked we should make it clear that action would not be justified unless this happened.

Southwood asked that Ministers should address, as part of the adjustment of the framework of the agricultural policy of the EC, the general problem of changing the 'novel pathway for pathogens' represented by inadequately sterilised animal products used in animal feed. Work on this in the Community is already under way in two areas - in discussion of the Community's proposal to lay down harmonised standards for the disposal of animal waste, and in work by the Scientific Veterinary Committee on the treatments necessary to neutralise the BSE agent. ⁷

3.204 Mr Lowson told the Inquiry that his response was cleared with his veterinary colleagues and endorsed by Mr Andrews, and suggested that:

. . . it would be transmission by the feed route, not [just] experimental inoculation, that would justify the imposition of a ban (in practice of course, when such experimental transmission by experimental inoculation was confirmed, the advice from SEAC was that this alone provided sufficient justification for action); and

It was not necessary or appropriate to do any work at that time on measures to implement a ban either generally or in connection with meat staining and sterilisation regulations. This was because, firstly we could not reasonably have attempted to predict what action, if any, would be recommended by the Government's scientific advisors in the event of transmission occurring. Secondly, not much work would be needed to put the necessary legislation in place so it was not necessary to prepare until these uncertainties were resolved (a supposition that was borne out in practice). ⁸

3.205 On 10 July 1990 Mr Andrews put a submission to the Minister advising on each of the points set out in Mr Maclean's minute of 5 July 1990. In relation to the ban on offal in pig and poultry feed he attached the note as provided by Mr Lowson. Mr Andrews commented on Mr Lowson's views:

I agree with the comment. But if we wanted to move on this, how would we resist pressure on the ovine offals? This morning's discussion underlined the problems that could build up for the rendering industry.

⁹

Agriculture Select Committee's inquiry into BSE

3.206 On 10 July 1990 the House of Commons Agriculture Select Committee's Fifth Report on BSE was published. The report covered a range of BSE issues, including the incorporation of SBO in pet food and non-ruminant rations. The Committee noted the Minister's resistance to making the PFMA's voluntary ban on the inclusion of SBO in pet food statutory, and stated that 'in this instance, which is not one of pure science but political judgement, we take the opposite view.' The Committee thought that 'with a disease as distressing as BSE, people are entitled to expect that the food they feed their pets should be protected by the same basic legislative safeguards as their own food, particularly in view of the uncertainties surrounding the newly identified feline encephalopathies'. It therefore recommended that the PFMA's voluntary ban on SBO in pet food be made statutory. ¹⁰

3.207 On the proposal for a statutory ban on feeding cattle offal to pigs and poultry, the Committee stated that it was a view with which it had some sympathy. It noted that MAFF had resisted a statutory ban due to a lack of scientific evidence, and then commented on UKASTA's voluntary ban:

We understand the reasons for this measure which are, first, to maintain public confidence and, secondly, to insure against the remote possibility that BSE is transmissible to other species; and we trust that, in judging how long to keep it in force, the industry will be guided by the latest scientific evidence. ¹¹

3.208 Whilst the Committee felt that it did not take enough evidence to reach firm conclusions of its own, it advised that the Government should establish an expert committee to examine animal feeds and advise on the need for industry regulation. ¹² This led to the establishment of the Lamming Committee in 1991 (see Chapter 2).

Pressure from the food industry

3.209 On 3 August 1990 Mr Lowson minuted Mr Maslin and Dr MacOwan about discussions with the Food and Drink Federation (FDF). FDF representatives had met Mr Capstick, Mrs Attridge, Mr Lowson and Dr Metters on the previous day to discuss their concerns about BSE and the commercial damage they were suffering. Mr Lowson's minute stated:

They pressed hardest on the question of excluding specified bovine offals from feed for non-ruminant animals. Individual consumers, and major purchasers (notably education authorities) were looking for products which derived from animals that had been fed on material which contained nothing unfit for human consumption. We went through all the usual arguments and Mr Capstick made it very clear that unless new scientific evidence became available (and [SEAC] was likely to review the evidence in this area) the Government would not impose any kind of ban. In the light of this the FDF side asked whether they could have some guidance notes that they could use with their customers. Dr Metters was not keen on this because [SEAC] have not formally looked at the evidence or expressed any formal opinion. But I do not see why we should not act in the same way here as we have done in the case of milk, namely providing material which sets out the justification for the line that we have taken, on which those interested can draw, without going as far as providing an authoritative on the record statement about the safety of the products concerned endorsed by the Department of Health. ¹³

3.210 Dr Metters received a copy of this minute, and noted in manuscript that the point he had made 'was that we should not attempt to second guess [SEAC], and as [SEAC] had this on their agenda it would be better to wait pending their view'. ¹⁴

Experimental transmission of BSE to a pig: SEAC recommends an animal SBO ban

3.211 On 16 August 1990 Mr Lowson submitted to Mr Gummer a paper, to be put to SEAC at its meeting on 19 September 1990, on the inclusion of SBO in feed for non-ruminants. In his covering minute Mr Lowson noted that Mr Gummer wanted to clear the paper before it was submitted to SEAC, together with papers on slaughterhouse practices and scrapie in sheep. Mr Lowson sought Mr Gummer's approval for the attached animal feed paper, and explained that the other two papers would be put forward in due course. The animal feed paper quoted the Southwood Report's conclusions in relation to pigs, poultry and pets - essentially that no action was called for other than research. It gave details of unsuccessful efforts to transmit kuru to poultry and to pigs, and it described the CVL's experiment to transmit BSE to pigs, which had to date produced no positive results. It set out by way of summary and conclusion:

Although cats have succumbed to a spongiform encephalopathy, and have been infected experimentally with CJD, no major pet species, pig or poultry have been shown to be susceptible to spongiform encephalopathies transmitted by ruminant material, even by intracerebral inoculations, and there is no significant evidence of pigs, poultry or dogs having been infected with any scrapie like disease. Pigs and poultry will have been exposed to the BSE agent over as long a period as cattle have been, without succumbing to the disease, and the total quantity of agent in the specified offal is now likely to be a downward trend. There is wide scope for pet owners to avoid material which they consider unsuitable, in spite of the absence of evidence.

There does not therefore seem to be any current evidence on which to take the view different from the Southwood Working Party's. This position would need to be reassessed if there was evidence that the inclusion of material derived from specified offals in pig and poultry feed or pet food was substantially higher than before the offals ban was introduced, but that is certainly not the case at present.

The Committee is invited to endorse these conclusions. ¹⁵

3.212 The paper was overtaken by the events that we now turn to describe.

3.213 On 20 August 1990 a positive result was recorded in the CVL's experimental efforts to transmit BSE to pigs. One pig had been diagnosed by post-mortem pathology as having developed a spongiform encephalopathy. A confidential pathology report submitted by Mr Wells to Mr Michael Dawson, Research Officer, CVL Virology Department, included the following remark:

The result, albeit confined to one animal in the experimental challenge group is incontrovertible evidence of the transmissibility of BSE to the pig by simultaneous intracerebral, intravenous and intraperitoneal inoculation routes. ¹⁶

3.214 Mr Meldrum told the Inquiry that he decided that the discovery should be kept confidential until SEAC had had an opportunity to review and discuss it. However, he informed Mr Gummer by telephone as soon as the preliminary results were known and they discussed the matter via video link. ¹⁷

3.215 On 23 August 1990 Dr Pickles reported the discovery to Sir Donald Acheson.

The minute noted:

CMO should be aware that a pig inoculated experimentally (ic, iv and ip) with BSE brain suspension has after 15 months developed an illness, now confirmed as a spongiform encephalopathy. This is the first ever description of such a disease in a pig, although it seems there are no previous attempts at experimental inoculation with animal material. The Southwood group had thought pigs would not be susceptible. Most pigs are slaughtered when a few weeks old but there have been no reports of relevant neurological illness in breeding sows or other elderly pigs.

. . .

An urgent meeting is being called of [SEAC] but since key members and the chairman are now overseas at a meeting this may not be until the week beginning the 3^rd September. Points for consideration:

1. In view of the long term exposure of pigs to scrapie without ill effect, does this suggest the species range for BSE is wider than that of scrapie, and if so what are the implications?
2. should the feeding of ruminant protein including BSE and scrapie-Infected offal to pigs now be discontinued?
3. is any action needed to protect humans, eg extending the offal ban to pigs?

. . .

For information, there are now 9 cats with feline spongiform encephalopathy, suggesting this is indeed a new disease and exposure to BSE unlike exposure to scrapie has been hazardous for cats.

Mr Maclean was informed last night and has agreed an early meeting of [SEAC] is required to give advice on which decisions will be made. In the meantime, he does not want to go public. Mr Maclean is expected to advise Mr Gummer. In these circumstances, CMO might like to consider whether [Mr Dorrell] should be informed. ¹⁸

3.216 Sir Donald Acheson informed Mr Dorrell of the diagnosis of the pig on the same day:

While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. An important point to take into account is that it appears that brain material from sheep infected with scrapie has never been experimentally injected into pigs and it may well be that pigs would also be infected by this route.

At the moment there is insufficient information on which to base any further action. In particular I do not think that it is necessary for the Medicines Control Agency or the Procurement Directorate to take any action about porcine materials. The next step should be to await the result of discussions at the next meeting of the Tyrrell Committee which will be held early in September. I have discussed the matter with Professor David Tyrrell and he agrees. Mr Maclean has been advised of the situation. ¹⁹

3.217 A meeting of SEAC was called at short notice on 7 September 1990 to consider the implications of the experiment results. A paper, prepared by Mr Meldrum, which considered the preliminary results of the experiment and considered whether as a consequence any changes to animal and health controls should be recommended, was before the Committee. The paper outlined the experiment results and noted that:

The Committee will wish to consider whether the transmission of BSE to one pig under challenging experimental conditions alters our scientific knowledge of the disease to an extent whereby additional animal or public health controls measures should be recommended to Ministers. ²⁰

3.218 On the animal health implications the paper noted:

15. The committee will also wish to consider whether there is a need to make recommendations for further action relative to the animal health implications of BSE. There are a number of options:

Do Nothing

16. The argument would be that the result is not a surprising one, given the weight of challenge and method used. It is a laboratory experiment and is quite different from the position in field conditions. For instance, the oral route of transmission is less efficient than the parenteral route by a factor of 10⁵ (Kimberlin and Walker, 1983). The monitoring of the adult pig herd nationally has not revealed any case suggestive of a scrapie-like sub-acute spongiform encephalopathy. Furthermore, most pigs are slaughtered at under 7 months. Thus, even if transmission were possible through the feed route, the vast majority of animals would be too young to pose any risk.

Legislate to ensure that meat and bonemeal derived from specified offal cannot be used in Pig Rations

17. Many industry and consumer organisations have advocated that the Government should legislate to prevent the use of processed specified bovine offals in pig and poultry rations and, indeed, in pet (dog and cat) food. The Government's response has been to point to the lack of scientific evidence to warrant such a course. Clearly the situation has changed in that, for the first time, a transmissable spongiform encephalopathy has been recorded in a pig. Although the range of scientific and other arguments and counter-arguments do not, perhaps, point to this measure being necessary on strict scientific grounds or at least until more evidence becomes available from transmission studies, it would, in practice, simply add the weight of legislation to an arrangement which is already operating, de facto on a voluntary basis. This is the option that holds most attraction for the Ministry's veterinary advisers and would ensure that bovine offals that are not permitted to be used for human consumption are not used in the food of livestock or poultry either. Such action might defuse a situation in Germany whereby guarantees are now being sought that imported pet food does not contain any bovine material of UK origin.

Ban the use of ruminant-based meat and bonemeal as a Feed Ingredient in Pig Rations

18. This would represent the most radical solution. It would deal not only with concerns about BSE agent being re-cycled to pigs, but also the continuing exposure of pigs to the scrapie agent from sheep. The logic of such a course would, almost inevitably, require that such rations are also banned from use in other livestock - poultry and horses are also in pet food. In the latter case the evidence from the investigations arising from the 10 cats which have succumbed to a spongiform encephalopathy is that we are probably witnessing a new disease in cats. However, it could be argued that pursuing such an option would be over-reaction since there is no evidence of a porcine encephalopathy under natural conditions and it is possible that pigs are not susceptible to BSE by the oral route but only when presented with a massive challenge.

19. The consequences of following this option are very serious indeed. There would be major repercussions for the rendering industry, which would reverberate throughout the agri-food cycle. There is currently no practical or viable alternative use for the 400,000 tonnes of meat and bonemeal which is produced annually. This would mean that it would have to be buried or incinerated after processing. Cost estimates put this at about £70 million using burial and £150 million using incineration. It would mean an increase of something between 1p-2p per pound of meat. But it is unlikely that all this additional cost would be borne by consumers. Even if it were, it would only have a small impact on the retail price index. This, in turn, would put further pressure on the meat market and place the UK industry at a competitive disadvantage even though we have in place far more comprehensive control measures than any other country. There would also be some spin off in Europe making it more difficult to export pig meat as the public would perceive such action as tantamount to an admission that pig meat presented a public health hazard. ²¹

3.219 At the meeting SEAC accepted CVL's conclusion that the experimental result provided 'incontrovertible evidence' of the transmission of BSE to pigs. The points emphasised by SEAC included:

1. the pig had become infected after receiving a massive dose of BSE infected material by a highly efficient route i.e. intracebral, intraperitoneal and intravenous inoculation with brain tissue from cattle affected with BSE. This demonstrated the susceptibility of pigs to spongiform encephalopathies, but, as only one of the pigs had succumbed, did not demonstrate the degree of susceptibility;
2. the clinical symptoms shown by the pig could not have been easily confused with those of any other condition. Therefore, it was unlikely that more than an occasional case had occurred and gone unnoticed in the field and the symptoms were sufficiently distinct for an effective monitoring programme to be put in place; and
3. many questions remained unanswered; for example, would pigs be susceptible to smaller doses, or larger doses given by mouth; would scrapie produce spongiform encephalopathy in pigs under similar conditions; did the tissue of sick or healthy animals contain infectious BSE? ²²

3.220 The minutes of the meeting record that:

It was very difficult to draw conclusions from one experimental result for what may happen in the field. However it would be prudent to exclude specified bovine offals from the pig diet.

Although any relationship between BSE and the findings of a spongiform encephalopathy in cats had yet to be demonstrated, the fact that this had occurred suggested that a cautious view should be taken of those species which might be susceptible. The 'specified offal' of bovines should therefore be excluded from the feed of all species. ²³

3.221 However, the Committee concluded that there were no grounds for extending the ban on the use of ruminant protein to non-ruminants, provided SBO was excluded. ²⁴

3.222 On 14 September 1990 Mr Lowson put a submission to Mr Gummer, which set out the proposed action in light of the experimental transmission of BSE to a pig. ²⁵ He noted that SEAC was due to meet the following week to finalise its advice. He said:

They can be expected in particular to recommend that the specified [bovine] offals excluded from human consumption and protein derived from them, should be banned for use in feeding to animals as well. A separate submission will be coming forward seeking Ministerial approval to an Order which achieves this. The aim will be that it should come into force as soon as the decision is announced. ²⁶

3.223 It continued:

A ban on the use of specified offals in animal feed will no doubt lead to claims for compensation from the Industry, as it will effectively make meat and bone meal derived from them unsaleable . . . It is therefore recommended that when this point is raised we should take a negative line. Nevertheless the ban can be expected to lead to further costs being passed onto slaughtering and livestock industries by renderers and knackers.

. . .

Consultation has so far been restricted to a very limited circle. However as the ban on the use of the specified offals for animal feed will apply throughout Great Britain, and will need to be mirrored in Northern Ireland legislation too, I hope that the Minister will agree to our telling colleagues from the other Agricultural Departments about what is happening. We will also, if the Minister agrees, set up a meeting for interested organisations as soon as the information is released. ²⁷

3.224 SEAC issued formal advice on 20 September 1990, following its meeting on the previous day. The advice stated:

Since this result shows that pigs can get spongiform encephalopathy, even though there is no evidence that they have done so in the field, we believe that pigs should no longer be fed with protein derived from bovine tissues which might contain the BSE agent, i.e. those 'specified' bovine offals that are already excluded from human consumption. It would make sense to extend this prohibition to feed for all species, including household pets, as other species have now developed spongiform encephalopathies. We are aware that many animal feed compounders and pet food manufacturers are already applying such a ban on a voluntary basis. ²⁸

3.225 In a statement to the Inquiry, Dr Tyrrell said:

It was the rapid increase in the BSE epidemic, the occurrence of more cases of FSE and the results of the pig transmission experiment which led SEAC to give the advice we did on the extension of the SBO ban. Before then (September 1990), we were not asked to advise on the extension of the SBO ban.

It was important to consider humans before other animals. It should be remembered that prior to the test results of the pig transmission experiment, pigs and poultry were not known to be susceptible to TSEs. Breeding pigs, in particular, were thought to have received a very high exposure to the same type of contaminated MBM as cattle but without any evidence of the occurrence of TSE. The issue of symptomless hosts was considered very carefully because it could apply to all domestic and farmed animal species. ²⁹

3.226 Mr Meldrum concurred that the result from the pig experiment had also changed the landscape for MAFF:

It was not until . . . August 1990, that the result from the pig persuaded both SEAC and us to change our view and to take out of pig rations any residual infectivity that might have arisen from the SBOs. ³⁰