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Fact sheet: Badgers and Bovine TB (bTB)
Bovine TB (bTB) is an infectious and contagious
disease of cattle caused by the bacterium Mycobacterium bovis (M.
bovis). Although the main reservoir and natural host of M. bovis
is cattle, human beings and a wide range of mammals, including
badgers and deer, are susceptible to the bacterium. In the 1930s,
approximately 2000 people a year in the UK died from the disease,
contracted either through infected milk or close contact with
infected cows (1). The subsequent pasteurisation of milk and
compulsory slaughter of infected cattle greatly reduced the
incidences (1).
bTB is rarely fatal in cattle, with signs of
infection usually only appearing in advanced cases, but it does
lead to reduced milk yields, making it a particular concern for
dairy farmers (2).
According to the Government, the number of
cases is increasing in England and Wales, with 27,598 infected
cattle slaughtered in 2007 (3). However, junior Defra minister
Joan Ruddock has said that 91 per cent of cattle herds were free
of it in 2008 (30). This compares to approximately 90,000 dairy
cows culled annually due to mastitis (infection of the udder),
31,000 due to lameness and 125,000 due to infertility
(4).
Bovine TB and Badgers
There are less than 300,000 badgers in Britain.
Protected by laws to prevent badger baiting, licences can be
granted by the Government for ‘disease control’ and ‘research’
reasons. As of June 2007, there were around 10.3 million cattle in
the UK (38). bTB cases have risen sharply since the 1980s and
around one in six herds in Western England and Wales were put
under restriction in 2007 (27).
Cattle farmers have long
blamed badgers for the spread of bTB and
since the mid-1970s tens of thousands of
badgers have been killed in an attempt
to control the disease. However, post mortem
examinations revealed that more than 80 per cent of those badgers
were disease free and in some infected areas no badgers were
infected (5). A Defra survey from 2002 to 2004 found that six out
of seven badgers killed on roads in areas of high infection were
free of the disease (6).
In 1998, the Independent Scientific Group on
bTB (ISG) was formed after a report by Sir John Krebs (Oxford
University) claimed there may be a case for badger ‘culling.’ The
ISG’s investigation included the Randomised Badger Culling Trial (RBCT),
costing £34 million and taking 12,000 badgers’ lives (24). The
report was published in 2007 (25) and ISG chairman, Professor John
Bourne (Animal Health, University of Bristol), reported that
“badger culling cannot meaningfully contribute to the control of
bTB in Britain.”
The report also found that ‘culling’ would
increase the spread of the disease as surviving badgers would
wander outside of their normal range after their social group had
been destroyed. TB infections in cattle increased by 27 per cent
after the cull in areas where badgers were the main suspects (27).
Even the Government’s Agriculture Committee
believe cattle movements and husbandry play a much greater role in
the spread of the disease than infected wildlife (7, 8). The ISG
also identified herd size and cattle movements as having
“particular relevance” and that cattle-to-cattle transmission was
the “main cause of disease spread to new areas”. Average herd size
has more than doubled to 107 since bTB was at its lowest in the
1970s and the ISG recognised that infections increased with larger
herds (25).
Bourne’s categorical findings were
challenged by the Government’s Chief Scientific Advisor, Sir David
King, who rushed out his own report within months, urging a
‘cull’. The King report was smaller, had fewer experts – and only
met for a single day (41). Bourne and Nature, the leading science
journal, heavily criticised the King report as “hastily written”,
“superficial”, riddled with “small mistakes” and appeared to have
been “written to please the farmers” (26). The result is that it
gave the Government an excuse to instigate a cull to appease
farmers should they want to.
Lords Krebs, who founded the original
badger cull trials, was also highly critical of the King report.
He has stated that improved cattle testing and keeping badgers and
cattle separate would cost less than a ‘cull’ are “as likely to
work”. He also expressed concern that a badger cull across the UK
could kill at least 170,000 animals – more than half the UK
population (41).
Any badger ‘cull’ will be an animal welfare
disaster. Snaring and gassing are incredibly cruel but the main
method is likely to be live cage traps and night shooting. With
shooting, many badgers will simply be injured while traps cause
huge distress. Both methods will leave cubs to starve to death in
the setts, as the ISG acknowledges (25).
Until recently, Northern Ireland had the worst
bTB incidence anywhere in Europe but has virtually halved it since
2002 through cattle controls and without killing badgers. It now
has fewer cases per 1,000 cattle than either Wales or England
(28). The Republic of Ireland has virtually eliminated badgers in
most cattle farming areas yet the number of herds infected is
still twice as high as in Britain (28).
In July 2008,
Environment Secretary Hilary Benn announced that licences would
not be issued for killing badgers in England, as he believed that
‘culling’ could make the situation worse. While in Wales, the
intention to kill badgers was announced in April 2008, with the
intended areas not being identified until the autumn. The move in
Wales was denounced by Viva! and groups as diverse as The National
Trust and The Badger Trust, as a blatant move to appease farmers.
Wales’ chief vet, Dr Christianne Glossop, has admitted that
badgers could be wiped out in certain parts of Wales and the
‘cull’ could last into the 2030s (36).
This rush to slaughter ignores new, non-lethal
solutions. An injectable badger vaccine is expected by 2010 and an
oral version by 2014 while a cattle vaccine is expected in 2015
(30).
Cattle Movements and testing
In 1990, there were 173 recorded outbreaks
of TB in cattle but by 2007, they had increased to 2,229
with 27,598 cattle slaughtered (3). This followed the
rapid re-stocking of farms after the 2001 foot and mouth disease (FMD)
epidemic. Under EU regulations cattle
must be routinely tested for bTB, with infected animals
slaughtered and movement restrictions placed on the farms. During
the 2001 FMD outbreak, most TB testing was suspended and, in
breach of EU regulations, Defra failed to impose movement
restrictions on those herds not tested (10).
Despite several highly-contagious diseases in
UK cattle, over 14 million movements take place every year as
farmers buy and sell stock (11). Just as TB cases are increasing,
so are the number of movements, with 619,107 more cattle moved in
2006 than 2005 (40). Cattle movements more than quadrupled between
1999 and 2006 and involved around 110
million animals (39). Movements dropped in 2007 but only
because of FMD restrictions.
Movement of cattle in the periods
between routine herd TB tests has long been recognised as a cause
of new infections, even in relatively disease-free areas.
The ISG report also made
clear that present methods of control - surveillance, testing and
slaughter - are not working. The truth is, tests are highly
inaccurate, missing around one third of all infected animals,
leaving them to re-infect other cattle (35). It went on to say
that better farming practices and not ‘culling’ were likely to
reverse the increase in bTB
(25). Even former
Defra Minister, Ben Bradshaw, highlighted the near irrelevance of
badger slaughter by admitting that 80 per cent of bTB outbreaks
are caused by cattle (11).
Farmers are compensated
for every animal that is slaughtered because of bTB - up to £1,924
for dairy cows and up to £3,755 for beef cattle (32).
Cattle Husbandry
The demand for
badgers to be killed has diverted attention away from the many
serious health problems faced by intensively-reared cattle -
pneumonia, E. coli, coccidiosis (a fatal diarrhoea),
salmonella and mastitis. They are all increasing and it is
attributed to ‘poor nutrition’, ‘poor management’ and ‘poor
welfare’ by the Government’s Animal Health Report, 1997 (12).
Similar considerations must apply to the spread of bTB.
Disease does not solely result from contact
with a pathogen but also from an animal’s inability to deal with
that pathogen. Stress reduces the body’s ability to fight disease
and intensive farming produces animals who are physically and
mentally stressed – none more so than the modern dairy cow.
High stocking densities
increase stress, as do high milk yields and both have increased
dramatically over the last 30 years. Milk has gone up from an
average of 3,700 litres annually to 8-10,000 in the modern,
high-yield Holstein (16). Forced to give birth to a calf every
year in order to keep this enormous milk supply going,
dairy cows spend seven months out of every year
simultaneously pregnant and producing large quantities of milk.
This crushing double
burden results in a quarter of the national dairy herd being
killed every year – physically exhausted at only four to five
years old when they could naturally live to be at least 20 (17).
On top of this immense physical stress, dairy cows also suffer the
repeated emotional trauma of having their newborn calves torn away
from them within 48 hours of birth. An unbearable anguish that
would take its toll on any mother.
Although dairy cows graze outdoors from April
to October, for the remaining six months of the year they are
confined in indoor cubicles (18). The overcrowded, unsanitary
conditions and high humidity lead to high levels of lameness and
mastitis. It is also an ideal environment for transmission of bTB.
The Irish bTB study confirms this (15).
Cows who once grazed mainly on grass are now
also fed concentrated, high-protein feeds such as soya and maize
to increase their milk yields, typically forming 30-50 per cent of
their diet. This seems to affect their health as grain-fed cattle
can have 100 times more E. coli 0157:H7 in their
gut, for example (19). This, combined with a fall in the
nutritional quality of animal feed, appears to have reduced their
ability to fight disease. The lack of genetic diversity in modern
farmed animals also plays a part (12). Also grazing has its
problems as the common practice of slurry spreading can represent
a potential source of bTB (15, 22).
The Vegan Solution
If, like us, you are outraged by this
scapegoating of badgers as a cover for cruel, incompetent and
unsustainable farming practises, there is one blindingly obvious
solution – reject milk and other dairy products and switch to a
vegan diet.
References
1. Institute for
Animal Health online: http://www.iah.bbsrc.ac.uk/public_info/topics/Mastitis.html
2. University of
Oxford (2005). Press release: Cattle movements the most
significant factor in spread of bovine TB, 26th
May. http://www.admin.ox.ac.uk/po/news/2004-05/may/26.shtml
3. Defra (2008) TB
Incidences in
Great Britain – Cattle.
http://statistics.Defra.gov.uk/esg/statnot/tbpn.pdf
4. Sibley, R.
(2003). Rethink health strategies. Farmers Weekly. February
28th 2003
5. Defra (2003).
Update on Bovine statistics. TB Forum paper TBF 87, points
13-15 www.Defra.gov.uk/animalh/tb
6. Defra (2005)
Road Traffic Accident Survey (RTA), 2002 – 2004.
7. Gilbert et al.
(2005). Cattle movements and bovine tuberculosis in Great Britain.
Nature 435, 491-496; 2005. 26 May 2005.
8. Phillips, C.,
Foster, C., Morris, P. and Teverson, R
(2001). The role of cattle husbandry in the development
of a sustainable policy to control M. bovis infection in cattle.
Report to the Ministry of Agriculture, Fisheries and Food.
10. Wildlife and
Countryside Link Statement on Bovine TB, May 2004.
http://www.badger.org.uk/tb/WCL-statement-2004.pdf
11. Badger Trust (2005)
Bovine TB Strategy. Available from: www.badger.org.uk
12.
Soil Association Policy Paper: Animal
Health – The Prevention of Infectious Livestock Diseases
(2002). Available from: www.soilassociation.org
15.
Griffin, J. M., Hahesy, T., Lynch, K., Salman,
M. D., McCarthy & Hurley, T (1993).
The association of cattle husbandry practices, environmental
factors and farmer characteristics, with the occurrence of chronic
bovine tuberculosis in dairy herds in the Republic of Ireland.
Preventive Veterinary Medicine, 17, 145-160.
16. Farm Animal Welfare
Council (1997) Report on the Welfare of Dairy Cattle.
17. Roebuck (2005) Herd
health and machinery integral to profitability. Farmers
Guardian, May 6.
18. Defra (2002) Dairy
cow welfare throughout the year. Papers presented at DEFRA/ADS
meeting on 6 Nov. 2002. Easton College, Norwich.
19. Couzin J.,
1998, ‘Cattle diet linked to bacterial growth’, Science 281
pp1578-1579.
20.
Udris, G. A. (1983). Trace elements in the
preventive treatment of bovine TB. Vet.
Moscow, 2 17-20.
21. HMSO (1997).
The Report of the Chief Veterinary Officer: Animal Health 1997.
London: The Stationery Office.
22. Hahesy, T.,
Scanlon, M., Carton, O. T., Quinn, P. J. and Lenehan, J. J.
(1992). Cattle manure and the spread of bovine tuberculosis.
Tuberculosis Investigation Unit, University College Dublin.
Selected Papers 1992, 1-6.
24. McCarthy, Michael (2008). The Big Question:
Should badgers be culled to check the spread of bovine
tuberculosis in cattle?. Independent. April 2006.
25. Independent Scientific Group on Cattle TB
(2007). Bovine TB: The Scientific Evidence: A Science Base for a
Sustainable Policy to Control TB in Cattle: An Epidemiological
Investigation into Bovine Tuberculosis
26. In for the cull. Nature – International
Weekly Journal of Science 450. November 2007.
27. Meikle, James (2008).
Background: Badgers and bovine TB.
Guardian. April 2008.
28. Badger Trust Cymru Report (2008). Facing
the senseless slaughter: the fate of Wales’ badgers.
29. Gassing ruled out as a culling option.
Farmer’s Guardian. 6 March 2008.
30. Bovine TB: DEFRA defends dithering
government, Farmers Weekly, 21 March 2008
31.
Badger culls spark tourism boycott
ultimatum, Daily Post, 15 May 2008
32. Defra (2008)
Compensation for Bovine TB, BSE,
Brucellosis and Enzootic Bovine Leukosis
35. Lawson, Trevor (2008)
Badger Trust Press release
36.
Badger cull could be ‘hugely
expensive’, Farmer’s Guardian, 30 May 2008
38. Defra (2007) Agriculture in the UK (2007),
Chapter 3: The Structure of the
Industry
39.
Rural Payment Agency figures
40. Email from Kathryn Wood, Management
Information Team, Rural Payment Agency, 6 June 2008
41.
There are better ways to curb TB, says founder of badger cull
trials, Western Mail, 24 June 2008
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