1p. Minimising heat and other stresses during animal transportation improves animal welfare and has driven EU legislation
Submitting InstitutionsUniversity of Edinburgh,
Unit of AssessmentAgriculture, Veterinary and Food Science
Summary Impact TypePolitical
Research Subject Area(s)
Mathematical Sciences: Applied Mathematics
Engineering: Civil Engineering
Commerce, Management, Tourism and Services: Transportation and Freight Services
Summary of the impact
Impact: Policy / animal welfare / economic. European Directives on
Animal Welfare have been changed to improve animal comfort during
transport. Our research has provided a basis for establishing
comfort/discomfort at an objective, physiological level through response
modelling and the quantitative assessment of the effects of thermal
conditions. The definition of optimum transport environments has
underpinned improved transport vehicle design and operation and formed the
basis of the development of regulations for improved animal welfare.
Significance: ~60 billion animals are transported world-wide each
Beneficiaries: EU policy makers (leading to revised Directives),
UK Government departments (especially Defra), and animals during
Attribution: Prof. Mitchell (SRUC).
Reach: All EU Member States, Canada, and the US.
Globally, it is estimated that over 60 billion animals are transported
annually and the welfare of these animals is an issue of major public and
political concern worldwide. Animal welfare in transit is the subject of
constantly developing legislation, which must be based on sound scientific
evidence that prioritises animal welfare. Prof. Mitchell (Professor of
Physiology and Animal Welfare, employed 1981-onwards) developed a research
programme that focused on these issues. The research, which has been
continuously supported by Defra and a number of industrial partners since
1995, used physiological and behavioural modelling [3.1] to provide
quantitative indices of the stress felt by livestock in transit. The
severity of the stress and the nature of the responses have been used to
define the ideal transport conditions and practices and to identify
acceptable ranges and limits for imposed stressors; in particular heat
stress [3.3]. This involved the development indices of thermal loads
including the development and application of the concept of Apparent
Equivalent Temperature (AET), which allows quantification and modelling of
the physiological effects of temperature and absolute humidity for poultry
in transit. The model has been evaluated and validated under commercial
transportation conditions and this was central to the success of the
project. A key part of the research has been developing new techniques to
measure the stress experienced by animals in transit such as
radio-telemetry which was used to record the physiological response of
animals to a range of transportation conditions and stressors including
temperature [3.2]. Numerous other markers of physiological stress have
been identified and applied which allow for continuous assessment and
point sampling to determine the degree of stress imposed in transit and
the effects upon animal welfare.
Further physiological and welfare outcome modelling has been applied to
the design, development and evaluation of non-mechanically ventilated
livestock transport systems [3.4] under a wide range of weather
conditions. It has also been used to assess the performance of
mechanically ventilated vehicles, provide information for improving them,
and for assessing the welfare conditions encountered by animals being
transported [3.5, 3.6].
References to the research
3.1) Mitchell, M. A. and Kettlewell, P. J. (1998). Physiological stress
and welfare of broiler chickens in transit: Solutions not problems!
Poultry Science. 77 (12): 1803-1814. http://tinyurl.com/nplozps
3.2) Kettlewell, P. J., Mitchell, M. A. and Meeks, I. M. (1997). An
implantable radio-telemetry system for remote monitoring of heart rate and
deep body temperature in poultry. Computers and Electronics in
Agriculture. 17: 161-175. http://dx.doi.org/10.1016/S0168-1699(96)01302-6
3.3) Mitchell, M. A. (2006). Using physiological models to define
environmental control strategies. In Mechanistic Modelling in Pig and
Poultry Production, Eds. R.M. Gous, T.R. Morris, C. Fisher, CABI
International, Wallingford, Oxfordshire, UK, pp 209-228.
3.4) Kettlewell, P. J., Hoxey, R. P., Hampson, C. J., Green, N. R.,
Veale, B. M. and Mitchell, M. A. (2001). Design and operation of a
prototype mechanical ventilation system for livestock transport vehicles.
Journal of Agricultural Engineering Research. 79: 429-439. http://dx.doi.org/10.1006/jaer.2001.0713
3.5) Knezacek, T. D., Olkowski, A. A., Kettlewell, P. J., Mitchell, M. A.
and Classen, H. L. (2010). Temperature Gradients and Physiological
Responses During Winter Broiler Transportation In Saskatchewan. Canadian
Journal of Animal Science. 90: 321-330. http://dx.doi.org/10.4141/CJAS09083
3.6) Villarroel, M., Barreiro, P., Kettlewell, P., Farish, M. and
Mitchell, M. A. 2011. Time derivatives in air temperature and enthalpy as
non-invasive welfare indicators during long distance animal transport.
Biosystems Engineering. 110 (3): 253-260. http://dx.doi.org/10.1016/j.biosystemseng.2011.07.011
Details of the impact
The impact of our research has been improved animal welfare through
changes in legislation, new codes of practice and better vehicle design
and operation. Specifically:
Definition of thermal comforts ranges for livestock made available to
the industry to improving transportation practices: The concept of
AET is one of our most important contributions to the field. It has been
adopted in both industry and in regulatory practice, as well as by
breeding companies (e.g. Ross — Aviagen Manual).
Direct inputs to European and UK animal transport legislation (EC
1/2005): The research has enhanced the understanding of the
conditions animals face during transportation and the stress that places
upon them. The definition of optimal or target thermal conditions in
transit and acceptable limits for temperature and absolute humidity is the
foundation of legislation relating the thermal conditions in transit for
poultry, cattle, pigs and sheep (e.g. EC 411/98 and EC 1/2005) and the
on-going review of legislation.
Our work features in European Food Safety Authority (EFSA) Opinions on
which European Transportation Legislation was based (EC411/98 and EC
1/2005). The impact is apparent in the recommendations made concerning
poultry transportation in the EFSA Opinion / Report of 2011 which in turn
forms the basis of the recommendations for future revision of EC 1/2005.
Provision of the basis for the design and operation of mechanical and
improved passive ventilation systems on commercial transport vehicles
(as embodied in legislation): our research demonstrated the efficacy
of mechanical ventilation of animal transport vehicles in reducing thermal
stress and improving animal welfare. This led directly to the development
and evaluation of improved passive and mechanical ventilation systems on
commercial vehicles, which has also been incorporated into current
The earliest modelling studies underpinned the development of the Concept
2000 poultry transporter, which uses mechanical ventilation. The
manufacturers developed fan-ventilated animal transporters for red meat
species using our research and the associated legislative requirements.
Indeed mechanical ventilation is now mandatory for all higher standard
vehicles in Europe taking livestock on long journeys, defined as exceeding
8 hours duration.
More recent work (e.g. for Defra) has directly addressed the long
distance transport of pigs, acceptable thermal envelopes for livestock and
the influence of journey times on the welfare of pigs. The outputs of
these studies have fed directly into Defra policy development and the
revision and amendment of current European legislation.
Economic benefits due to the reduction of mortality during transport
and improved product quality (e.g. in broiler chicken transportation):
The work has improved animal welfare by reducing stress during
transportation and with over 56 billion broiler chickens transported world
wide every year, better vehicle ventilation and control of the on-board
temperature could decrease previously significant economic losses. Animals
that die whilst being transported cannot be sold, and so represent a loss
of profit, but the new transportation systems are estimated to have
reduced the in-transit mortality rates by 50%. An estimate of mortality
under UK transport conditions prior to the introduction of ventilated
systems, was ca 0.1%, which means with production of ca
850 million chickens every year, losses of 850,000 birds was commonplace.
Improvements to transportation are conservatively estimated to have saved
425,000 birds per annum.
Sources to corroborate the impact
5.1) European Food Safety Authority, 2011; EFSA Panel on Animal Health
and Welfare (AHAW); Scientific Opinion concerning the welfare of animals
during transport. EFSA Journal. 9 (1): 1966. [125pp.]. http://dx.doi.org/10.2903/j.efsa.2011.1966
5.2) "The welfare of animals during transport". Scientific Report of the
Scientific Panel on Animal Health and Welfare on a request from the
Commission related to the welfare of animals during transport (Question N°
EFSA-Q-2003-094). Adopted on 30th March 2004. http://tinyurl.com/nlohok3
Defra research reports (contact John.Tayleur@ahvla.gsi.gov.uk) or:
5.3) AW0940 — Epidemiological studies to determine travel times for pigs:
Defra — (2008-2012) http://tinyurl.com/pj9rc8w
5.4) AW0820 — Transcontinental road transport of breeder pigs — effects
of hot climates: Defra — (2006-2009) http://tinyurl.com/oc8djz6
5.5) AW0939 — A review to appraise the evidence for acceptable
temperature envelopes for pigs (2008-2009) http://tinyurl.com/qzcl7np
5.6) The Animal Transport Association http://tinyurl.com/qz8thke
5.7) Heerings (Netherlands) Vehicle Construction http://tinyurl.com/p2nomjh
5.8) Veterinary Consulting Services. David Pritchard (formerly senior
veterinary consultant for animal welfare at Defra) http://tinyurl.com/oqb9amu
5.9) Defra. Welfare in Transport Team http://tinyurl.com/p5vo8y6
5.10) Pennsylvania State University — A quality assurance program for
handlers and transporters of poultry — training manual for certification.
5.11) Livestock transport requirements in Canada. http://tinyurl.com/okkgpsv