Sunday, February 29, 2004

Mr Speaker stifles the bovine TB inquisition

From The Sunday Telegraph (Christopher Booker)

I reported last week that the Tory MP Owen Paterson, a front-bench agriculture spokesman, was planning on Tuesday to break the record for the largest number of written questions on a single subject ever tabled to ministers on one day. The purpose of his 300 serious and carefully crafted questions was to obtain information crucial to a better understanding of the crisis that now threatens our cattle industry as a result of the epidemic of bovine TB in Britain's soaring badger population.

Following my report, which was widely picked up by the media, including the BBC Today programme, a serious row broke out behind the scenes when Mr Paterson was told that, on a ruling by the Speaker, Michael Martin, his 300 questions were not acceptable. On Wednesday, in clear breach of parliamentary convention, the questions did not appear on the Commons order paper.

This decision by the Speaker had serious constitutional implications. In recent years, it has become increasingly difficult for MPs to call ministers to account or to get straight answers to questions. Oral questions can be so easily side-stepped that they have become a farce, and debates likewise, since these are now time-limited and ministers merely have to flannel until time runs out.

Written questions, to which ministers and civil servants are obliged to give considered answers under the rules of the House, have become almost the only remaining means whereby MPs can get the information they need to monitor the Government's performance.

After tense negotiations involving the Tory Chief Whip, a compromise was eventually arrived at whereby Mr Paterson was permitted to table his 300 questions on TB over four days. He may not thus establish any records. But his campaign to tease out the data necessary to assess the scale of the crisis facing Britain's countryside is back on track.

Tuesday, February 24, 2004

Parliamentary Questions

24 Feb 2004: Column 331W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what the natural predators of the badger are, other than man; and what effect they exert on the United Kingdom badger population. [153961]

Mr. Bradshaw: Adult badgers have no natural predators, other than man in Britain. It is not unusual, however, for badger cubs to be killed by dogs, foxes and sometimes by adult badgers1.

24 Feb 2004: Column 332W

The impact of non-human induced mortality on the national badger population has not been quantified.

1 The Handbook of British Mammals (1991). Third Edition. Edited by G. B. Corbet and S. Harris. Blackwell Scientific Publications, Oxford.

24 Feb 2004: Column 332W

Andrew George: To ask the Secretary of State for Environment, Food and Rural Affairs how many badgers have been culled in each of the (a) proactive and (b) inactive cull areas in each of the selected trial zones in each year since the trials commenced. [155081]

Mr. Bradshaw: The Randomised Badger Culling Trial compares 30 areas of 100 km 2 , grouped into 10 triplets. One of the following three "treatments" is allocated to each trial area:

'Proactive' culling where badgers are trapped and culled at the outset of the trial and at intervals afterwards.
'Reactive' culling where badgers are trapped and culled from social groups associated with farms which have a confirmed incident of bovine TB during the course of the trial.
'Survey only' areas where no trapping or culling takes place. Setts are surveyed regularly to check for signs of unlawful removal of badgers. These areas act as a scientific control against which the impact of the two culling strategies can be measured.

Culling in the reactive areas of the trial has been suspended.

Details of the badgers culled in the proactive and reactive treatment areas are given in the following table:

Badgers taken
to 12 Jan
2004
Triplet Proactive (P) May 1998
to Jan
1999 May 1999 toJan 2000 May 2000 toJan 2001 May 2002 to Jan 2003 May 2003 to Jan 2004 Total
or Reactive (R) P R P R P R P R P R P R
A 55 0 0 34 149 47 52 36 256 117
B 238 0 85 73 74 34 49 84 172 110 618 301
C 246 0 111 178 126 115 132 101 615 394
D 293 0 368 122 661 122
E (1)744 0 96 62 258 126 1,098 188
F 451 0 248 145 103 290 802 435
G 428 0 205 172 144 84 777 256
H 162 0 231 16 71 143 464 159
I 219 0 175 94 394 94
J 441 0 187 0 628 0
Sub total 238 386 73 1,970 246 2,057 641 1,662 1,106 6,313 2,066
Total (P and R) 238 459 2,216 2,698 2,768 8,379

(1) Combined total for initial and follow-up cull completed in the same culling year
Note:
No data for May 2001-January 2002 when trial suspended due to FMD

24 Feb 2004: Column 332W

Andrew George: To ask the Secretary of State for Environment, Food and Rural Affairs what targets have been set for the bovine TB testing of herds in the last five years for which figures are available; how many have been completed; and how long it will take to clear the backlog of required tests. [155082]

Mr. Bradshaw: The State Veterinary Service has two targets relating to TB testing of cattle herds:

(a) 95 per cent. of herds to be tested within one month of the due date, and
(b) 100 per cent. of herds to be tested within three months of the due date.

The following table details the performance figures for the years where figures are available.

2001 2002 2003(2)
Number of herds due to be tested 12,207 19,877 15,524
Completed tests within one month of the due date (percentage) 14.5 47.4 78.7
Completed tests within three months of the due date (percentage) 22.7 65.0 92.7
(2) to end September

The number of tests overdue at the end of December 2003 was 3,623 of which only 163 were more than 12 months overdue (provisional data). This is similar to the number of overdue TB tests recorded before the FMD epidemic.

24 Feb 2004: Column 333W

The number of overdue TB tests has remained more or less stable since April 2003, with no significant trend up or down. It is therefore considered that the clearance of the backlog of TB tests, which accumulated during the FMD epidemic, has been completed.

24 Feb 2004: Column 333W

Andrew George: To ask the Secretary of State for Environment, Food and Rural Affairs what budget was set by her Department for each year for all aspects of bovine TB research, testing, culling, compensation,

24 Feb 2004: Column 334W

fieldwork and other costs for the last five years for which figures are available; and what the actual spending was in each year. [155083]

Mr. Bradshaw: Historical information on the budgets originally set for various elements of the bovine TB programme is not readily available and can be provided only at disproportionate cost. However, a breakdown of the actual spend for the last five financial years is shown in the following table:

Expenditure on bovine TB in Great Britain: 1998–99 to 2002–03 Expenditure in £000
1998–99 1999–2000 2000–01 2001–02 2002–03
Compensation(3) 3,491 5,303 6,632 9,243 31,146
TB testing 7,247 8,329 8,675 3,571 12,398
Randomised Badger Culling Trial (RBCT) and associated research 2,988 4,392 6,630 6,001 6,479
Other research (not including RBCT) 2,541 4,114 5,266 6,112 6,824
Other costs(4) 8,617 9,002 8,996 5,557 17,055
Total (rounded figures) 24,883 31,141 36,199 30,485 73,902
(3) Includes compensation paid for cattle and deer slaughtered as a result of TB control measures.
(4) Includes State Veterinary Service staff costs and diagnosis carried out by the Veterinary Laboratories Agency.
Fieldwork costs are included in the expenditure shown for the RBCT and associated research.

Monday, February 23, 2004

Parliamentary Questions

23 Feb 2004: Column 125W

Mr. Hoyle: To ask the Secretary of State for Environment, Food and Rural Affairs if she will make a statement on the spread of bovine TB in (a)the North West and (b)each county in the North West. [153887]

Mr. Bradshaw: Statistics are collected by areas covered by Animal Health Divisional Offices (AHDOs). Carlisle AHDO covers Cumbria. Preston AHDO covers Lancashire, Greater Manchester and Merseyside.

In Cumbria, there were 3,969 registered herds in 2003, with 1,949 TB herd tests carried out. Provisional data show there were 70 new herd TB incidents in 2003, of which 15 were confirmed (three remain unclassified). In 2002. there were 4,041 registered herds, and 1,504 herd tests carried out. There were 33 new herd incidents, of which 10 were confirmed.

The increase in incidence in Cumbria is giving some concern. TB testing is now being carried out on all farms in an area of South West Cumbria known as the Furness Peninsula, concurrent with a survey of badgers (killed in Road Traffic Accidents) and deer (culled, or found dead, with suspicious lesions) in the same geographical area. It is hoped the data collected will help inform decisions about TB controls in the area.

In the area covered by Preston AHDO, there were 3,160 registered herds in 2003, with 918 herd tests carried out. Provisional data show five TB herd incidents, with one confirmed. In 2002, there were 3,303 registered herds, and 1,126 herd tests. These resulted in nine TB incidents, with none confirmed.

There has been a recent breakdown in a herd in Greater Manchester, but this has not yet been confirmed at post-mortem.

23 Feb 2004: Column 125W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what the preferred foods of adult badgers are; and on what foods they rely when their preferred foods are in short supply. [153966]

Mr. Bradshaw: Badgers eat both animal and plant material and are considered to be largely opportunistic in their choice of food. Although they feed on a wide range of foodstuffs, earthworms are the most important single item in the diet of British badgers. Because these and other food types are taken according to their availability, the diet of badgers varies both geographically and seasonally 1 .

23 Feb 2004 : Column 126W

1 The Handbook of British Mammals (1991). Third Edition. Edited by GB Corbet and S. Harris. Blackwell Scientific Publications, Oxford.

23 Feb 2004 : Column 126W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs to what diseases, other than tuberculosis, badgers are susceptible. [153978]

Mr. Bradshaw: Rabies and distemper have been found in badgers in other European countries but these diseases have not been detected in UK populations. Badgers are also susceptible to bacterial infections, including leptospirosis and salmonellosis.

23 Feb 2004 : Column 126W

Paul Flynn: To ask the Secretary of State for Environment, Food and Rural Affairs what the total paid in compensation to farmers for bovine tuberculosis was in each of the last five years; and what percentage of the total was paid in excess of the market value of the animals destroyed. [155000]

Mr. Bradshaw: The following table gives the compensation paid to farmers for cattle slaughtered under TB control measures 1998 to 2002.

£ Compensation paid
1998 3,605,242
1999 5,770,983
2000 7,307,797
2001 7,074,125
2002 23,138,512

There is evidence from a National Audit Office study carried out in Wales in 2002 and from other sources that, overall, average compensation payments are significantly higher than average market prices. However, it is difficult to quantify the extent of this disparity.

Thursday, February 12, 2004

Parliamentary Questions

12 Feb 2004: Column 1559W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs (1) what specific characteristics are exhibited by badger groups under population stress; [153964]

(2) what the effects of over-population are on the health of badger populations. [153965]

Mr. Bradshaw: Central Science Laboratory studies suggest that body weight in badgers is density dependent, with lower average weights occurring as group size approaches carrying capacity. The association between body weight and badger density suggests that food is a major factor limiting badger numbers.

The notion that badger populations are “over-populated” is erroneous. Badgers display a sophisticated regulatory mechanism, where fecundity and mortality are in equilibrium to maintain the population at a level which the habitat will support.

There is no information linking the health status of badgers to population density. TB is known to occur in low density badger populations, and studies by Central Science Laboratory have demonstrated that there is no linear relationship between badger density and TB prevalence.

12 Feb 2004: Column 1559W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs whether domestic cats are susceptible to infection by M. bovis bacillus; whether any such infections have been recorded; and whether the infection can be transferred to man. [153919]

Mr. Bradshaw: Like most terrestrial mammals, domestic cats are susceptible to infection by Mycobacterium bovis (M. bovis). Cases have been recorded in Great Britain and other countries but current incidence is very sporadic. TB in cats is not notifiable although it is good practice to contact the State Veterinary Service (SVS) if it is suspected. The SVS will undertake to assist with the identification of M. bovis in any clinical or pathological specimens.

The infection can be transferred to man, therefore, if a confirmed case of M. bovis infection in a cat comes to the attention of the SVS, the Divisional Veterinary Manager will inform the Consultant in Communicable Disease Control (CCDC) of the local health authority. Investigation of the TB status of any human contacts is the responsibility of the CCDC. If TB is reported in a farm cat the SVS will instigate tuberculin check tests of cattle on that farm, and of potential contacts on neighbouring premises.

12 Feb 2004: Column 1559W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what measures are taken by her Department to ensure that guidelines on testing badgers for M. bovis infection before release by animal hospitals are properly observed. [153923]

12 Feb 2004: Column 1560W

Mr. Bradshaw: Animal hospitals treating sick or injured badgers are not legally required to test animals for bovine tuberculosis before they are released from captivity.

To minimise the risk of animal hospitals accidentally spreading tuberculosis Defra facilitated development of the voluntary protocol for the rehabilitation and release of badgers. This was drawn up by the RSPCA, National Federation of Badgers Groups and Secret World Wildlife Rescue. The protocol provides comprehensive guidance on the precautions necessary to protect the welfare of badgers and critically, to minimise the risk of transmitting bovine tuberculosis. The protocol is promoted by the organisations above and is available via the internet at: http://www.badger.org.uk/action/badger-rehabilitation-protocol-contents.html

12 Feb 2004: Column 1560W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what assessment has been made of whether infection of M. bovis bacillus between infectious female badgers and their offspring leads to an increase over time in the incidence of infection within a social group. [153924]

Mr. Bradshaw: From research carried out by the Central Science Laboratory, it is believed that the transmission of infection from mothers to cubs may be important in the maintenance of TB infection in badger populations. There is a correlation between the presence of infectious females in a group and the proportion of TB positive cubs. No information is available as to whether this has influenced the incidence of infection within a social group over time.

12 Feb 2004: Column 1560W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs (1) what assessment she has made of the accuracy of the size of the badger population in Great Britain as reported by the National Badger Survey; [153953]

(2) what estimate she has made of the minimum size of the badger population in the United Kingdom necessary to ensure its continued survival; [153958]

(3) what estimate she has made of the optimum size of the badger population in the United Kingdom; [153959]

(4) what estimate she has made of the maximum size of badger population which can be sustained in the United Kingdom; [153960]

(5) what estimate she has made of the change in the badger population in Great Britain since the last National Badger Survey. [153974]

Mr. Bradshaw: In a 19951 report reviewing the status of mammals in the United Kingdom, commissioned by the Joint Nature Conservation Committee, the badger population estimate provided by the 1980s National Badger Survey was given the highest possible rating for accuracy (one on a scale of one to five, where one is the most accurate). As the 1990s National Badger Survey 2 followed the same methodology as the earlier exercise, its results can be afforded a similar high level of confidence.

12 Feb 2004: Column 1561W

I can confirm that the Department has not estimated of any of the following population parameters for badgers in the United Kingdom:

The minimum population size necessary to ensure its continued survival.
The optimum size of the population.
The maximum size of population that can be sustained.

In the report of the 1990s National Badger Survey2, the authors concluded that there was “substantial scope for further badger population expansions” as badger setts were still scarce or absent in many suitable areas (especially in East Anglia and parts of Scotland). However, the authors also said that “in areas with established badger populations, it was unlikely that further significant increases would occur”.

Since there has been no national badger survey since the mid-1990s, we do not know whether the population level has changed in the interim.

As I explained in my reply to the hon. Member's earlier question, 26 January 2004, Official Report, column 1W, my Department has been funding the Winter Mammal Monitoring Project3 which is being carried out by the Mammal Society and the British Trust for Ornithology. This is a pilot study intended to develop a terrestrial monitoring system for British mammals, including badgers. Early findings confirm the pattern of distribution reported in the National Badger Survey, but it is too early to say whether, and by how much, badger numbers have changed since the 1990s.

1 "A review of British mammals: population estimates and conservation status of British mammals other than cetaceans" (1995). Stephen Harris, Pat Morris, Stephanie Wray and Derek Yalden. Published by the Joint Nature Conservancy Council, Peterborough, UK.

This publication is available online at: www.jncc.gov.uk/Publications/review britishmammals/areviewofbritishmammalsall. pdf

2 "Changes in the British badger population, 1988 to 1997" (1997). G. Wilson, S. Harris and G. McLaren. People's Trust for Endangered Species (ISBN 1 85580 018 7)

3 Further details and preliminary results from the Winter Mammal Monitoring Project are available online at: www.bto.org/survey/special/mammal results.htm

12 Feb 2004: Column 1561W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what assessment she has made of the (a) proportion of adult badgers in Great Britain currently infected with M. bovis bacillus and (b) proportion of those that are infective. [153955]

12 Feb 2004: Column 1562W

Mr. Bradshaw: National data, on which such assessments would need to be based, are not available.

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs on what grounds legal protection has been afforded to badgers. [153962]

Mr. Bradshaw: The badger benefits from legal protection introduced to outlaw cruelty towards animals. For example, the Protection of Animals Act 1911, which among other things, made the baiting of animals illegal, and the Wild Mammals (Protection) Act 1996, which made certain specified acts of cruelty illegal.

In addition, there are legal restrictions on the range of methods that can be used to kill or take badgers. This protection was introduced to outlaw inhumane and/or indiscriminate methods of control. The key legislation in this respect is the Wildlife and Countryside Act 1981. Some of these restrictions apply to all animals, while others apply only to animals, like the badger, listed on schedule 6 of the Act.

There have also been specific laws to protect badgers. These were introduced as a welfare measure to combat illegal badger baiting, and also as a conservation measure in response to declines in badger numbers in the 1970s and 1980s. The various statues specifically relating to badgers were consolidated under the Protection of Badgers Act 1992.

12 Feb 2004: Column 1562W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what the limiting factors are on the size of the badger population in the United Kingdom in the absence of predation and intervention by man. [153963]

Mr. Bradshaw: The abundance of wild animals is ultimately limited by the availability of key resources. In the United Kingdom, food and suitable sites for setts are likely to be the key constraints on the size of the badger population.

12 Feb 2004: Column 1565W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs

(1) what the criteria are for designating an animal species in the United Kingdom as (a) an endangered and (b) a protected species; [153956]

(2) under what circumstances an animal previously categorised in the United Kingdom as endangered or protected is deregistered or otherwise removed from the list; and what conditions must be met for statutory protection to be removed; [153957]

Mr. Bradshaw: As previously mentioned in the answer given to the hon. Member on 26 January 2004, Official Report, column 1W, the animal species listed on schedule 5 of the Wildlife and Countryside Act 1981 are reviewed every five years. My previous answer details the criteria used for assessing whether species should be added to the schedule for the Fourth Quinquennial Review, which will be consulted upon in 2004. The Quinquennial Review criteria relate only to taxa that is endangered or is likely to become endangered.

Endangered species are also identified through inclusion in Red Data Books, where the threats to survival of species are assessed using internationally recognised criteria.

12 Feb 2004: Column 1566W

Part of the Quinquennial Review process is also used to assess whether the species that have been protected by listing on schedule 5, still merit protection. The criteria used are the same as those given in my previous reply of January 26.

Wednesday, February 11, 2004

Parliamentary Questions

11 Feb 2004: Column 1441W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what assessment has been made of whether there are (a) physiological and (b) neurological differences between rabbits and moles, and badgers, which would affect their response to poisoning by fumigants, in terms of the distress and pain caused. [153926]

Alun Michael: All pesticides used as fumigants are subject to strict regulatory control and must be approved by Ministers before they can be marketed or used in the UK. Those seeking approval for such products are required to provide data to ensure that the product is safe, effective and humane.

No specific assessment is made of physiological or neurological differences between rabbits and moles in response to poisoning by pesticide fumigants. However, the Advisory Committee on Pesticides considered a report in 1996 on humaneness of vertebrate control agents, which resulted in the loss of one pesticide fumigant substance and approval for the remaining pesticide fumigant products to continue. Data on humaneness of pesticide fumigants in relation to the target test species, such as rabbits and moles was considered.

Use of pesticide fumigants against badgers, which are protected species, is not permitted, except in special circumstances, and as such would not have been considered.

Tuesday, February 10, 2004

Parliamentary Questions

10 Feb 2004: Column 1298W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what her best estimate is of the staff time costs in replacing stolen, lost and damaged traps used in the operational Krebs triplets areas. [153925]

Mr. Bradshaw: It is not possible to quantify the staff input into individual components of the Randomised Badger Culling Trial.

10 Feb 2004: Column 1299W

For the average number of field staff employed in operations associated with the culling trial, and total cost of the Wildlife Unit by financial year, I refer the hon. Member to the answer given on 22 January 2004, Official Report, column 1366W.

Friday, February 06, 2004

Parliamentary Questions

6 Feb 2004 : Column 1109W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what the sensitivity of the test used on translocated badgers is in (a)positive response and (b)negative response. [150583]

Mr. Bradshaw: The test, which is generally used, for the detection of TB in translocated badgers is a test for antibodies (the Brock Test). This is generally accepted to have a low sensitivity (the ability to detect diseased animals). However it is difficult to give accurate values for the sensitivity because euthanased animals are not always subject to laboratory culture.

Where a badger translocation is carried out under licence (from Defra or English Nature) each individual badger is tested three times. If any of the three results are positive, the badger is euthanased. Any other badger that has been in contact with the positive testing badger is also euthanased, regardless of the results of its own tests

Where an orphaned or previously injured badger is translocated by an animal centre or similar body they follow a voluntary code of practice (drawn up by the RSPCA, National Federation of Badgers Groups and Secret World Wildlife Rescue). Any animal to be relocated is tested three times and, if it tests positive, is euthanased. This protocol does not advise in the destruction of badgers who have had contact with a test positive badger. It should be emphasised that this voluntary protocol was not devised or approved by Defra.

The Veterinary Laboratories Agency is trying to develop a range of TB tests for badgers with improved accuracy, including a gamma-interferon test.

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs how many herds were placed under TB restriction in December 2002; and how many of those same herds were still under restriction in October 2003. [150571]

Mr. Bradshaw: A total of 725 herds were placed under movement restriction in December 2002. This includes 294 herds placed under movement restriction following disclosure of a new TB incident. The remainder were herds placed under movement restriction because the routine herd test was overdue.

6 Feb 2004: Column 1110W

Ninety six herds placed under restriction in December 2002 were still under restriction on 31October 2003 (66 of those as a result of an ongoing TB incident).

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs how many herds require 60-day testing for tuberculosis; and what the estimated annual cost is for this testing programme in 2003–04. [150587]

Mr. Bradshaw: All herds suffering a TB breakdown are subject to at least one short interval ("60-day") test. A total of 7,275 short-interval tests were carried out from April to December 2003, at an estimated cost (including administration costs) of £3,485k. The forecast cost for 2003–04 is £4,600k.

6 Feb 2004: Column 1110W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs

(1) pursuant to her answer of 8December 2003, Official Report, column 215W, what epidemiological inferences can be drawn from the observed seasonal trends in the incidence of TB in cattle; [150596]

(2) what further research she is planning into seasonal trends in the incidence of TB in cattle. [150712]

Mr. Bradshaw: The absolute number of new TB incidents disclosed every month is closely correlated to the rate of testing. Hence, the majority of incidents are detected in the winter months (October through March), when most herds are tested.

However, if the data are adjusted to take into account the seasonality of TB testing, there does not appear to be a clear seasonal pattern in the rate of new TB incidents disclosed each month (i.e. it is not possible to conclude that the herd incidence of bovine TB in certain months of the year is consistently higher than in other months).

Because of the difficulty in studying seasonality of TB infection, there are few reports investigating this aspect of the disease. However, the results of one such investigation was reported in a paper by Wilesmith et al (1982)1. They examined seasonal variations in the risk of acquiring infection between 1971 and 1976 for a Dorset cattle herd during an extensive TB herd breakdown. The data indicated that the April/May period presented the time of greatest risk. This correlated with possible exposure to re-infection at the start of the grazing season, exposure lasting for a relatively short time. However, re-exposure to infection was not necessarily the same as re-exposure to pasture, since some stock were out-wintered.

The Veterinary Laboratories Agency will continue to monitor epidemiological trends, including seasonality.

1 Wilesmith, J. W, T. W. A. Little, H. V. Thompson and C. Swan. (1982). Bovine tuberculosis in domestic and wild mammals in an area of Dorset. I. Tuberculosis in cattle. Journal of Hygiene, Cambridge 89: 195–210.

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs what percentage of M. bovis was isolated from (a)carcasses and (b)faeces from wildlife species tested in studies carried out by or on behalf of her Department and its predecessor since 1974. [150611]

6 Feb 2004: Column 1111W

Mr. Bradshaw: The information is as follows:

(a)All previous Defra information on M. bovis isolated from wildlife carcases was collated in the following review paper: Delahay, R. J., de Leeuw, A. N. S., Barlow, A. M., Clifton-Hadley, R. S. and Cheeseman, C. L. (2002). "The Status of Mycobacterium bovis Infection in British Wild Mammals: A Review". Veterinary Journal 163, 1–16.

(b)Two projects currently in progress involve sampling both live animals and carcase material from a variety of species. The data from these projects have not been fully analysed at this point so accurate figures are not available. Results from carcase material published in the OIE report on Wildlife disease 2003 showed that the prevalence of M. bovis infection was 2.9 per cent. in wildlife (669 cadavers, 20 positive cultures). The culture positive species were fallow deer, fox and muntjac.

Live sampling (samples including faeces) from over 4,000 small mammals (<30g) have shown that the prevalence of M. bovis is less than 0.3 per cent. The spoligotypes associated with these animals are largely of a type only found in small mammals.

6 Feb 2004: Column 1111W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs pursuant to the answer of 8 December 2003, Official Report, columns 21–18W, under what circumstances genetic structures of M. bovis undergo mutation following sequences of transmission, with particular reference to transmission between species; at what rate mutations occur; whether techniques and facilities are available to detect these changes; and whether back-mutation of bacilli from final host species would assist in the determination of the direction of inter-species transmission. [150847]

Mr. Bradshaw: As Mycobacterium bovis is transmitted over time there is evidence that hyper variable regions of its genome change, although most of the genome remains stable. Changes can be identified using molecular biological techniques. Hyper variable regions may change in both intra and interspecies transmission. There is no reason to believe that, except for very rare adaptive changes, the rate of mutation will increase as a strain moves between species.

The rate at which mutations occur depends on the region of the genome. Hence, single nucleotides have an average rate of change of about 10- 9 per nucleotide per generation. However, tandem repeats that show variable numbers (variable numbers of tandem repeats, or VNTRs), show a greater rate of change. Spoligotype changes are intermediate in rate between VNTR and single nucleotide mutations.

We use two main techniques to detect genetic variation in M. bovis. The first of these, spoligotyping, exploits a polymorphic region direct repeat (DR) locus in the genome that is composed of multiple 36bp DR copies interspersed by unique spacers, with strains varying in the presence or absence of spacers. The VNTR method targets 6 alleles (A-F) that vary in the length of internal repeat units, permitting strains to be differentiated on the number of repeats at each target; i.e. 7–5-5–4-3–3-3 would have 7 copies of allele A, 5 of B, etc. High throughput facilities for both of these techniques exist at the Veterinary Laboratories Agency

6 Feb 2004: Column 1112W

(VLA), allowing the molecular typing of about 4,000 to 5,000 strains per year. Our current models of the population structure of M. bovis suggest that the VNTR loci evolve faster than the DR repeat locus. Thus spoligotyping provides a global picture of the population structure and epidemiology of M. bovis in Great Britain, while VNTR typing has proved useful as a fine scale method for detecting local changes in the M. bovis population.

The evolution of the members of the Mycobacterium tuberculosis complex has led to specific host preferences; hence M. tuberculosis appears human restricted, while M. bovis consists of a series of clones with a wider mammalian host range. The process of host adaptation probably involves a number of discreet mutations, which would all need to revert to reverse the host adaptation. Back-mutation i.e. the reversion of mutations, occurs very infrequently. The rate for a specific single nucleotide reversion would be about 10- 9 X 10- 9 ( or 10- 1 8 ) per nucleotide per generation. Indeed, if some of these mutation events were deletions they could not revert without the re introduction of the DNA. These questions are being investigated using laboratory based molecular biological techniques at the VLA.

Monday, February 02, 2004

Parliamentary Questions

2 Feb 2004: Column 620W

Mr. Paterson: To ask the Secretary of State for Environment, Food and Rural Affairs pursuant to her answer of 10 December 2003, Official Report, column 522W, on badgers, whether the reference to the gassing of badgers being considered to be inhumane refers only to the use of hydrogen cyanide gas; and what gases are available for use for the slaughter of subterranean animals which have properties that do not engender distress in those animals. [150568]

Mr. Bradshaw: In his 1980 report, "Badgers, Cattle and Tuberculosis", Lord Zuckerman considered gassing as a method of capture. Having consulted the Government Chemical Defence Establishment at Porton Down, he recorded that:

"the only likely chemical alternatives to cyanide are carbon monoxide and nerve gases. The latter, however, are too dangerous to handle, and the former is, weight for weight, significantly less toxic than cyanide, and therefore likely to prove less effective than cyanide in practice."
He recommended that work be carried out to devise improvements in gassing procedures and this work concentrated on hydrogen cyanide. The Krebs Report points out that the subsequent investigation:

". . . cast doubt on the humaneness of this method of killing because research showed that badgers did not die immediately underground."
The following pesticides are currently approved for the control of subterranean animals:

Cymag, containing sodium cyanide, which generates cyanide gas for rat and rabbit control; and Luxan Talunex, and Phostoxin, both of which contain aluminium phosphide and generate phosphine gas for the control of moles, rats and rabbits.

These pesticides are approved on the basis that they are safe, effective, and do not cause unnecessary pain and suffering to the target animal.