Volume 5: Animal Health, 1989-96
2. The ruminant feed ban, 1989-96
The chronological account
Developments in 1993 - testing of ruminant feeds is proposed

Developments in 1993 - testing of ruminant feeds is proposed

The first BABs born in 1990 are reported

2.201 Meanwhile, on 3 February 1993 Mr Lowson provided Mr Soames with an update on BABs, of which there were now approximately 1,200. This included 73 suspected cases born during 1990. Mr Lowson reported that two suspects born in September and October 1990 were likely to prove positive, with horizontal transmission suspected for one of them. He continued:

Although the evidence of the effect of the feed ban is very strong in the age pattern of confirmed cases, and still enables us to look forward to a downturn in the number of newly-reported cases this year, it is becoming apparent that the disease will continue to be confirmed in animals born well after the ban. There are a number of possible explanations for this. The most likely, certainly in the majority of cases so far reported, is as we have already made clear publicly, that they were fed on ruminant protein after the July 1988 ban, either because of material carried over after that date, or the use of feed intended for other species, which could have quite legally have contained ruminant protein, and indeed until September 1990 the 'specified offals'. But it is also possible that other elements such as maternal or horizontal transmission have occurred to a limited extent but were undetectable whilst the influence of the feed source was so overwhelming. As the feed source is removed in younger age groups these alternative routes of transmission will become apparent. ¹

2.202 On 22 February 1993 Mr Meldrum wrote to Sir Richard Southwood, following his request for an update on BSE. Mr Meldrum explained that Mr Wilesmith would provide a full background soon, but in the meantime noted:

We are confident that progress is being made, albeit with a clear time lag in full effectiveness of the ruminant feed ban. Feed containing meat and bone meal was clearly available on farm for several months after the ban, largely due to carry-over of material produced beforehand, but also because it took longer than we would have liked to clear the supply chain. ²

Consideration of the inclusion of porcine material and tallow in ruminant feed

2.203 On 25 February 1993 Mr Lowson forwarded a submission to Mr Soames, seeking guidance on 'some relatively minor issues'. He recommended that since in practice operators were not incorporating porcine material into ruminant rations, no legislation should be implemented to make it illegal, as this could attract unwelcome negative publicity. Instead, MAFF should make it clear to the industry that they would reconsider the situation if things changed in practice (see paragraphs 2.157-2.163 concerning the deliberations on this advice). ³

2.204 The submission also proposed an amendment to the ruminant feed ban, to allow bovine tallow, which contained minute traces of protein, and dicalcium bone phosphate to be incorporated in ruminant rations. ⁴ This was in accordance with SEAC's view that incorporation of non-SBO tallow in ruminant rations did not present a problem. Mr Lowson commented that since this change reflected what was already believed to be the position, 'it is unlikely to provoke much controversy'. ⁵

2.205 The proposals were discussed during a meeting on 23 March 1993 attended by Mr Soames, Mr Capstick, Mr Lowson, Mr Taylor and Mr Maslin. Mr Soames agreed with the recommendation against banning the inclusion of porcine material in ruminant rations. However, he said that both he and the Minister had reservations about allowing material containing minimal quantities of ruminant protein to be fed to ruminants. Despite assurances from Mr Lowson and Mr Maslin that the proposed materials for exclusion from the ban were currently only included in error, Mr Soames said he would prefer to consider the matter at the Ministers' meeting the next day. ⁶ At that meeting, it was agreed that the amendment should not be made (see vol. 11: Scientists after Southwood). ⁷

Mr Bradley suggests the ELISA test should be employed in the field

2.206 On 26 March 1993 Mr Bradley suggested to Mr K Taylor that even though the ELISA test had yet to be validated in a blind trial, it would 'be useful to employ this test to ruminant rations in the field now'. He explained:

If it shows positive results it is well we know about them and deal with the problem. If it shows negative results the data can be used to reassure the EC and importing countries that our feed ban is now effective (even if it was not completely so after July 1988 for an indeterminate period). This would be valuable supporting evidence to enable us to recommence trading in cattle for breeding. ⁸

2.207 Mr Bradley also suggested that it was theoretically possible that the test, if sensitive enough, could detect the inclusion of tallow in compound rations. He thought, 'If this validation has not been undertaken it might be as well to do it'. Mr Bradley concluded:

Of course the presence of ruminant protein in ruminant rations does not equate with presence or absence of infection but it would be reassuring to know that it is now completely excluded from all ruminant rations. ⁹

2.208 Mr Taylor passed the minute to Dr Matthews for comment, who agreed with Mr Bradley. He informed Mr Taylor that he had discussed the issue with the VIS about three months previously and that development had been halted by the Worcester VIC's relocation. Dr Matthews further advised that the test still needed to be subjected to quality control validation, and that difficulty was being experienced in obtaining raw material for the purpose. Finally, no testing for cross-reaction with fishmeal had been done. Nevertheless Dr Matthews concluded that 'as it stands the test can identify and differentiate ovine and bovine protein in meat and bone meal and compound feed'. ¹⁰

2.209 Mr Taylor responded to Mr Bradley on 6 April 1993:

I agree that application of the test in the field is desirable, but am not sure that we are yet in a position to do so. Development work was halted during the relocation of Worcester VIC, and the test still needs to be subjected to quality control validation. I understand that there is some difficulty in obtaining equivalent raw material to that used when developing the test. Also, more importantly, no testing has yet been done to see if the test cross reacts with fishmeal, and I believe this must be done before the test can be used in the field.

I am grateful to you for reminding me of the importance of the subject, and am asking Danny to continue liaison with the VIS to ensure that the necessary validation is carried out as quickly as possible. ¹¹

2.210 On 19 April 1993, in response to a request by Dr Matthews for an update, Mr B Preece, SVO, advised that a quality control regime was being established. However, difficulties with the provision of quality assurance samples were being experienced, and alternative methods were being investigated. ¹²

Further consideration of BABs by SEAC

2.211 Mr Wilesmith and Dr Matthews prepared a paper summarising the investigations into BABs for SEAC's meeting of 22 April 1993. As at 2 April 1993, there were 1,791 confirmed BABs. Of those, 1,683 were born before 31 December 1988, with the remaining 108 born between 1 January 1989 and 31 October 1989. The two cases born in 1990 would be confirmed shortly, but there was no conclusive evidence of their likely source of infection. The paper repeated the view that there was still no evidence to suggest anything other than infected feed was sufficient to maintain the epidemic. It continued:

The full extent of what could be termed the 'carry-over' effect of feedstuffs manufactured before the statutory prohibition of ruminant derived protein in ruminant rations, which could have survived in the supply system, and were fed to cattle, has still yet to be realised quantitatively. In reality, this is probably impossible, but would appear to be longer than the 3 to 4 months shelf-life of commercial cattle feedstuffs. ¹³

2.212 During their meeting, Mr Bradley updated SEAC on the progress of the BSE epidemic. He pointed out the 'welcome signs of reduction in the age specific incidence of the younger age groups and in the report rate of cases compared to previous years'. He also noted the 'less welcome' BABs, but said there was no evidence of maternal transmission. SEAC supported a proposed case control study on BABs to establish what, if any, factors other than feed were involved. They also noted that, until the overall number of new cases began to decline, it was only possible to say that the trends 'looked promising but that we could not yet be confident the epidemic was beaten'. ¹⁴

Mr Taylor and Mr Bradley press for the ELISA test

2.213 Further to his correspondence with Mr Bradley in April 1993 (see paragraphs 2.206-2.209), Mr K Taylor minuted Dr Dawson on 20 July 1993. He pointed out that whilst BABs born in the months immediately following the introduction of the RFB could be explained by feed carry-over, 'it becomes far more difficult to point the finger at feed once we get into 1989, and we currently have 390 or so 1989-born cases'. He explained that a case control study was under way and said:

While retrospective testing of feed consumed in 1988 or later is obviously impossible, we are likely to come under increasing pressure to test feed currently in circulation. The industry is keen to make use of such a test, and as Ray [Bradley] has pointed out it could provide useful reassurance to potential trading partners. It may also be important in epidemiological terms if we find that the study concludes that the ban has not been wholly effective. ¹⁵

2.214 Mr Taylor's understanding was that the test had been developed at Worcester and Luddington due to their existing expertise in species testing of meats, and was not an area requiring major research and development funding. He asked:

How near are we to having a test that can be used on field rather than test samples? Can it be made available to local authorities on a commercial basis? Has it been tested on fishmeal or tallow? If there are problems with its development, it is possible to identify the difficulties and means by which they may be resolved sooner rather than later? I fear that we will be vulnerable to criticism if we are not able to test feed intended for ruminant animals fairly soon. ¹⁶

2.215 Mr Michael Prince, Senior Veterinary Investigation Officer (SVIO) at Luddington, advised Dr Dawson on Mr Taylor's queries on 28 July 1993. He said that the test was ready for use on field samples and that samples from Northern Ireland had already been tested satisfactorily. It had been tested satisfactorily on fishmeal, but not specifically on tallow. Fat did not appear to be a problem. Mr Prince explained that the test had given 100 per cent accuracy for 50 MBM samples and 24 compound feed samples, though the latter was not 'blind'. He continued:

We have been awaiting full validation by the QA Unit but since this is dependant on material prepared in this laboratory, I wonder whether there is any virtue in pursuing this. The trials described above are documented at this laboratory and should, I feel, suffice to validate the test. If this were acceptable the test would be ready for immediate use. ¹⁷

2.216 Following an EU Scientific Veterinary Committee meeting on 18 June 1993, Mr Meldrum minuted Mr Bradley on 30 July 1993 with comments on risk assessment of MBM. Amongst other issues, Mr Meldrum reiterated his full support for the 'mandatory zero tolerance adopted in the UK' for incorporation of MBM in ruminant rations. ¹⁸

2.217 Mr Bradley replied on 10 August 1993 and said:

I do not believe anyone will be advocating that a little ruminant derived MBM will be all right but a lot will not, but it is logical to suggest that the more that is fed the greater the risk will be if it was infected. I fully agree with your view of the need for the ruminant feed ban in the UK. However I would add that to be effective it must be enforced. I believe it would be helpful to show that it was effectively enforced by feed testing as advocated in the Lamming Report. ¹⁹

Cross-contamination is suspected and a feed testing programme is pursued

2.218 In a statement to the Inquiry, Dr Matthews explained that:

Evidence to support the hypothesis that cross contamination of feed was a problem did not accumulate rapidly. . . during the course of routine epidemiological investigations by veterinary officers during 1992 and 1993, MAFF became aware of cattle that supposedly had not consumed feed in which it had not knowingly been included. In many instances, where mothers for example were still alive, or where the incidence of disease in the herd was low, and horizontal transmission effectively ruled out, it inevitably led to considerations of risk following low dose exposure. ²⁰

2.219 Mr John Howard of MAFF's Animal Health (Disease Control) Division ²¹ and Mr Robertson discussed the enforcement issue. On 24 August 1993 Mr Howard minuted Mr Robertson, asking, 'Would it be possible to arrange for some voluntary random sampling to test for the presence of ruminant protein in ruminant feedingstuffs?' He said:

I understand that this sampling could contribute to the validation of the testing procedures which we need to have formally accepted. The results of such testing would provide at least an indication of the level of compliance with the ruminant feed ban, and the effectiveness or otherwise of our main control measure. I believe that we are vulnerable at present in having no evidence of this sort and depending upon the results of the random sampling we can propose what further action, if any, should be taken. ²²

2.220 On 16 September 1993 Mr Howard provided a background briefing paper on BSE to Mr Soames for a proposed seminar. The paper was also copied to the new Minister of Agriculture, Mrs Gillian Shephard. ²³ The paper had been 'agreed' by 'all concerned at Tolworth except Mr Taylor', who was due to provide comments on his return from overseas. Under the heading, 'Cases born after feed ban', the paper stated:

Up to 3 September 1993 there have been 4,010 cases confirmed in cattle born after 18 July 1988. The great majority of these cases had access to ruminant protein in their feed. If the ban was not working we would have seen at least 12,000 cases by this time.

Although the ruminant feed ban was introduced in July 1988, it is not surprising that it took a while to become effective as material in the system worked its way through. Ministers knew this was a possibility but did not wish to delay introduction by allowing a longer time for stocks to be used up. Most cases infected via feed after July 1988 were fed material containing meat and bonemeal by accident or by ignorance. The ban on the use of protein derived from specified bovine offals in animal feed introduced in 1990 also has an effect of reinforcing the ruminant feed ban by removing the offals most likely to contain the infective agent from the animal food chain. ²⁴

2.221 The paper then explained:

The trading standards officers of the local authorities have powers to check that unauthorised material is not used in animal feeding stuffs although no test has been available to prove illegal incorporation/sale/feeding of ruminant protein to ruminants. A test has however now been developed to differentiate between ruminant and other proteins in compound rations. [The practical application of this test in field conditions is now being considered.] ²⁵

2.222 It concluded by noting that a case control study of BSE in cases born after 30 October 1988 was underway to assess the risks of feed, maternal and horizontal transmission, with the results expected in 1994. ²⁶

2.223 On 21 September 1993 Mr Colin Maclean of the Meat and Livestock Commission (MLC) met Mr K Taylor, Mr Bradley and Mr Wilesmith to receive an update on BSE. In his note of the meeting, Mr Maclean recorded general BSE statistics and BAB statistics. He said:

Evidence that cumulative exposure is not a problem. It still looks as if each case is caused by one sporadic loading dose. ²⁷

2.224 On 1 October 1993, in the context of discussion on changes to the Bovine Spongiform Encephalopathy Order 1991, Dr Matthews informed Mr K Taylor that he had been reminded 'of the need to seriously discuss where we go with sampling of feed for the presence of ruminant protein'. He said that he had discussed the issue with Mr Wilesmith, who:

. . . appears to be more concerned about potential cross-contamination or accidental inclusion at mills manufacturing multi-species rations than with deliberate contraventions of the order. With respect to the mills we could simply visit to investigate current practices and precautions against cross-contamination, although we may not have powers of entry to do so. ²⁸

2.225 Dr Matthews explained that MAFF was seeking powers so that in the future they could routinely sample feed, without reasonable suspicion that the RFB was being breached, as required by the current Order. He noted however that:

. . . given the likely appearance of many more 1989 and 1990 born BABs, I do feel that we need to address the possibility that they may have been infected via feed, if only to allay public fears that ruminant protein is not in use today. While we had no test for the presence of ruminant protein in 1988 we do have a reasonable excuse for not policing the ban, but cannot avoid a more positive approach now. ²⁹

2.226 He listed a number of options for targeting sampling in the future:

a) random on-farm sampling nation-wide, with the aid of computerised selection;

b) random sampling at all mills, or possibly unannounced sampling at mills;

c) sampling on-farm, targeting herds with high incidence of BABs;

d) sampling on-farm whenever any BAB is reported or slaughtered;

e) sampling on-farm whenever BABs born in 1989 or later are reported or slaughtered;

f) sampling on-farm whenever BABs born in 1990 or later are reported. ³⁰

2.227 Dr Matthews recommended the final option, on the understanding that later born BABs would be indicators of a historical problem with feed if there had been contamination after 18 July 1988. He thought that if such contamination had existed in 1990, it might 'indicate real and continuing problems at specific mills'. ³¹

2.228 Dr Matthews also recommended that whenever a home-bred BAB born in 1990 or later was slaughtered, samples should be collected of any feed likely to contain protein, whether animal or vegetable, to which cattle could gain access. He said that the samples should be held until BSE was confirmed and then submitted for analysis. His 'major reservation' was that farmers would want the results divulged and 'should they have confirmed BABs and protein positive feed we could find ourselves caught up in litigation other than prosecutions for contravention of the BSE Order'. Furthermore, under the Order, sampling at mills or rendering plants would involve establishing intent to supply feed to ruminants. ³²

2.229 SEAC considered a progress report on BABs during its meeting on 7 October 1993. The report noted that of the 4,010 confirmed BABs, 3,392 were born in 1988, 614 in 1989 and 4 in 1990. The risk of feed being the source was high for 1,636 cases, medium for 1,756 and unknown for 618 cases. ³³ The minutes of the meeting record that:

The Committee was disturbed that the feed ban had not been as effective as early as hoped when the industry had given assurances that the material would be used up in 2-3 months. It was recognised that the level of infectivity in meat and bone meal produced just before the ban was still increasing due to recycling of bovine material and it is now obvious that compounders and farmers have taken longer to use up this material than expected. It was agreed that some of the present data were being overinterpreted for example by commenting on fluctuations in incidence in single months. Information on cases in the cohort born in 1990 would be critical. Mr Wilesmith's data on the decline in age-specific incidences in younger age classes, and other information supported downward trend in the epidemic. ³⁴

2.230 On 14 October 1993 Mr Howard advised Mr K Taylor, Dr Matthews and others that current legal advice was that while a regulation or order made under the Animal Health Act 1981 could provide for routine sampling of feedstuffs, it could not be used to extend the powers of entry required. Mr Howard said that he was pursuing the possibility of taking routine samples under section 73 of the Agriculture Act 1970. ³⁵

2.231 Mr Howard advised Mrs Davis on the same day that 'we have dropped at least for the time being the proposal for the routine sampling of feedingstuffs under the Animal Health Act 1981'. However, he continued:

I am wondering if we could use provisions already available in section 73 of the Agriculture Act 1970 . . . It appears that local authorities are already visiting feedingstuffs manufacturers premises and taking samples for analysis. As you know the purpose of our sampling would be to test for the presence of ruminant protein in feedingstuffs intended for ruminants which is banned under the BSE legislation. It seems to me that we could do this under section 73(3) of the Agriculture Act. ³⁶

2.232 On 4 November 1993 Mr Robertson responded to Dr Matthews's minute of 1 October 1993 regarding the establishment of a testing regime. He pointed out that 'We now have a reliable test for bovine and ovine material', and said that 'We must try to find a way of using the tests in the short term'. He argued that if MAFF did not have legal powers to take samples, 'we can surely rely on the co-operation of most farmers'. He concluded:

If we are going to worry about the possibility of litigation between farmers who have positive BABs and compounders of what appears to be contaminated feed we will never be able to use the test in farm situations. We may, in any case, be exaggerating the risk of such legal actions. ³⁷

2.233 Mr Howard pursued the legal issues with Mrs Davis again on 10 November 1993. He said:

I would be grateful if you could let me have your views about sampling. The ruminant protein ban is a key measure in our control policy and we are anxious to obtain more information to indicate whether or not animal protein from ruminants is being detected in ruminant feedingstuffs, and if so to what extent. ³⁸

2.234 In a statement to the Inquiry, Mr Meldrum said, 'It was about this time that I was becoming increasingly uncomfortable about the number of BABs that were being confirmed and the possibility that BSE infectivity was present in meat and bone meal intended for feeding to pigs and poultry was finding its way into cattle rations'. ³⁹

2.235 On 17 November 1993 Mr Robertson informed Mr Paul Gayford of the Veterinary Investigation Section that the Animal Health Group was content to take his advice that the ELISA test had been validated. However, this was so provided that he was confident that it could stand up to expert scrutiny in the event of prosecutions for contravention of the RFB. Mr Robertson said that they were awaiting legal advice on their powers to take samples, but hoped that 'we will shortly be in a position to submit material for testing at Luddington VIC, regardless of the advice given to us by the lawyers'. ⁴⁰

2.236 Mr Howard received the legal advice that he was seeking on 17 December 1993. Ms Shasa Behzadi advised that section 76, not section 73(3), of the Agriculture Act 1970 was relevant to routine sampling of feedstuffs. This gave an 'extremely wide' power for a local authority inspector to enter premises and take samples. In her view the provision conferred power to sample feedstuff on a routine basis to test for the presence of ruminant protein. The only qualification was that the powers would have to be exercised in accordance with the detailed provisions contained in section 77 of the Act on the division of samples and analysis by an agricultural analyst. ⁴¹

2.237 Mr Howard conveyed this advice to Mr K Taylor, Mr Eddy, Mr Robertson, Dr Matthews and Mr Bradley on 22 December 1993. He advised that there were no obstacles to carrying out sampling or taking prosecutions, but warned:

What is equally clear though is that the sampling and enforcement would be carried out by local authorities and not MAFF staff. Presumably this would mean that test results would be available in the local authority domain. Bearing in mind the sensitivity of BSE and the fact that the ruminant feed ban is the main plank of our controls, information suggesting that the ban was not working could be very damaging. Unless we could guarantee that test results would not be released to anyone but ourselves, at least in the early stages, it seems to me that we would be embarking on an extremely risky exercise. ⁴²

2.238 Mr Taylor replied on 31 December 1993:

Assuming that the legal advice is correct, and that one Act can be used to obtain evidence which may then be used in a prosecution taken for an offence against a different Act, there seems to be no reason why local authorities should not now be encouraged to collect samples for examination at Luddington VIC, and to take appropriate action if ruminant protein is found to be present where it should not be.

If contraventions are found the information will be damaging, whoever obtains the evidence. But I don't see that it matters much whether we or local authorities do so: we could hardly suppress information even if only we had it. Since the testing will be done at a VIC we will at least know the bad news before anyone else does.

If we wanted to limit the risk of embarrassment and still prove to the world that the law was effective we could, I suggest, simply publicise the fact that routine sampling was about to start. ⁴³