LAPS®

LAPS is a patented method to achieve an irreversible stun in poultry. Low atmospheric pressure is attained by using computer controlled slow decompression, which allows the body of the bird to adjust to changes in pressure and thus lose consciousness. LAPS sets a new paradigm for controlled atmospheric stunning without gaseous addition or electrical shock. The benefits of LAPS are not only humane, but also improve the economics of stunning and meat quality. LAPS has received a No-Objection letter from the USDA and CFIA and has the Seal of Approval for Humane Equipment by the American Humane Association.

The exact timings vary a little between birds and also between temperature settings (a family of decompression curves that are applied automatically at different ambient temperatures due to changes in air density), so only averages and time ranges can be given. The LAPS cycle lasts 280 seconds for chickens. During the first 40 seconds, we see few behavioural responses (some birds show mandibulation), then they begin to become ataxic (beginning to lose balance and posture) and may show headshaking. Between 50-70 seconds the birds lose posture (this is a behavioural indictor of loss of consciousness and is corroborated with changes in brain state). A few seconds after loss of posture the birds begin to show convulsions (wing flapping - these are involuntary reflex responses and normal), and by around 140 seconds on average the birds are motionless (in a non-recovery state).

EFSA is a European agency funded by the European Union that operates independently of the European legislative and executive institutions (Commission, Council, Parliament) and EU Member States. It was set up in 2002 following a series of food crises in the late 1990s to be a source of scientific advice and communication on risks associated with the food chain. The agency was legally established by the EU under the General Food Law - Regulation 178/2002. The General Food Law created a European food safety system in which responsibility for risk assessment (science) and for risk management (policy) are kept separate. EFSA is responsible for the former area, and also has a duty to communicate its scientific findings to the public.

Pain can be detected in birds by changes in patterns of behaviour, demeanour, as well as specific pain behaviours e.g.; guarding behaviour of an injured limb; looking at or pecking a painful area; escape behaviours. Several studies on LAPS have included detailed second by second observation of birds in large groups, as well as in small groups to observe individual bird behaviour. A catalogue of defined behaviours (an ethogram) of poultry was prepared including their known response to a range of stunning methods. The behaviour of birds was recorded by an infrared video camera allowing for detailed analysis using specialist computer software. The time of onset and cessation and/or counts of each behaviour were recorded. Detailed statistical analysis examined the patterns of behavior of each bird in relation to the events of before, during, and after the LAPS cycle. It also allowed comparison of the behaviour of birds during LAPS in the light or the dark and a sham study to examine the effect of the chamber alone on bird behaviour. No birds were observed performing escape behaviour. The range and patterning of behaviour seen was consistent between trials and experiments and was strikingly similar to that seen with stunning with inert gases. A randomised controlled study was conducted to examine the behaviour of birds which had received a suitable dose of analgesic (pain killer). Very similar sequences of behavior were seen in treated and untreated birds and these relate primarily to hypoxia. There were some differences in latencies and counts of specific behaviours of the birds, possibly reflecting a smoother induction of unconscious in analgised birds. Collectively the results did not provide convincing evidence that birds undergoing LAPS are experiencing pain.

EFSA conducted a very detailed review of the evidence and sought additional data and studies which the scientists provided. EFSA found that the scientific data on LAPS exceeded that available for other stunning systems in poultry (e.g. electrical waterbath and controlled atmospheric (gas) stunning). Due to this lack of comparable data, EFSA could not make direct comparisons of LAPS to these systems.

The EFSA expert panel reported that the median welfare hazard score for LAPS was 3.5 whereas gas stunning (with carbon dioxide) scored 7 and electric waterbath stunning was most hazardous with a score of 10. Lower scores equal lower risk of welfare hazard and LAPS received the lowest score. This assessment shows that the LAPS method leads the field in humane slaughter and should be specified for high welfare poultry schemes above other stunning systems.

LAPS and gas stunning with carbon dioxide share the welfare benefits of avoiding the handling of conscious birds, which also provides a better working environment due to lower dust and fewer injuries for the birds and handlers.

Carbon dioxide systems vary in their design, some tip out birds onto conveyors and some keep the birds in drawers which go through tunnels of gas.  Some systems use deep pits and some use chambers.  Each system has advantages and disadvantages according to their design.

Operational costs for gas stunning systems that use carbon dioxide are higher than LAPS because of the additional transport costs, storage costs, purchase costs, and supply risks of carbon dioxide.

The behavioural and physiological responses of birds to inert gases and LAPS are similar as both produce loss of consciousness due to hypoxia. In 2004, EFSA stated that, “In this regard, the use of hypoxia (less than 2% by volume of oxygen) induced by argon, nitrogen, inert gases or mixtures of these may be the best option from an animal welfare point of view.

The LAPS process is by design a more reproducible and consistent way of achieving gradual hypoxia since decompression produces the same level of hypoxia throughout the chamber at a pre-defined rate.

Because no inert gases are used during LAPS, it has an additional benefit over argon systems of having a lower carbon footprint as the energy involved in gas production and transport and storage are avoided.

In aviation and space medical science the effects of decompression are well understood. Explosive decompression occurs when pressure changes from ambient to near vacuum in less than 1 second. Rapid decompression is when it occurs in less than 10 seconds and slow decompression in more than 10 seconds. Smaller changes in barometric pressure can cause a variety of conditions in man and collectively are called dybarism. The LAPS process is not explosive or rapid decompression, and instead is somewhat equivalent to ascent in an unpressured aircraft. In man, during ascent, we observe loss of cognitive powers and motor skills, which precede an uneventful loss of consciousness. The stealth with which hypoxia can creep up on aircrew is the reason the aircrew have to be specially trained in stimulators to recognise the first signs of hypoxia. Such decompression may cause expansion of gases in closed cavities and this can cause pain in man including toothache, sinus and /or ear pain, and abdominal discomfort due to distension of air in the intestinal tract. Such signs are not seen for 15 minutes and whilst it is difficult to draw analogies between man and birds it appears unlikely they would be seen during the 50 to 80 second period in which birds are conscious in LAPS. There is a further range of conditions which occur with long term exposure to high altitudes such as decompression sickness and mountain sickness, but these require exposure of longer periods so are unlikely to be relevant to LAPS. Studies have been conducted to check if LAPS does cause such dysbaric effects on chickens. These have included pathological studies looking for damage (rupture of internal organs of the alimentary tract such as intestines colon, caecum, etc., as well as air sacs, lungs, joint cavities, and ruptured ear drums). No evidence has been found of ruptured internal organs or ear drums. An analgesic study was also conducted which may have revealed evidence of pain due to expansion of organs without rupture, but there was no convincing evidence that birds are experiencing pain.

Yes, it is legal to use LAPS for poultry in Canada. The CFIA gave LAPS “No Objection” in 2013.

Yes, it is legal to use LAPS in the UK.  Currently, the law allows the use of LAPS on broiler chickens weighing 4kgs or less and for the depopulation of chickens.  Further research is being conducted on broilers weighing more than 4kgs, layer chickens, and turkeys.  These limitations were put in place by EFSA due to the fact that all of the research was conducted on broiler chickens weighing less than 4kgs and not because of limitations of LAPS.  LAPS has successfully been used to irreversibly stun layer chickens, broiler breeder chickens, quail, and turkeys in the USA. http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:OJ.L_.2018.122.01.0011.01.ENG&toc=OJ:L:2018:122:TOC

EU Law allows for the Commission to introduce a novel or revised method to stun or kill animals, such as LAPS, providing that they have a positive opinion from EFSA as to whether the new method provides at least equivalent welfare to existing systems. When the EU Commission receives a positive opinion from EFSA on a novel stunning method, such as LAPS, they can then start a procedure to produce a proposal for a Commission Decision to change Regulation (EC) No. 1099/2009 to include LAPS. This then undergoes a legal process and approvals within the Commission. It is then passed to the Standing Committee on Plants, Animals, Food and Feed (PAFF Committee) for discussion and adoption. The Commission then arranges publication in the official journal and the Regulation is changed on the date of Publication or another date specified in the Decision. Then Member States can put in place procedures for the approval of the use of LAPS in poultry plants taking account of all the provisions of the Regulation and if necessary the advice of their national scientific support committee.

The European Commission has advised TechnoCatch, LLC that this process should take between 3 months and 6 months.

The physiology of other farm animals such as pigs is different to birds and further research is required to determine if LAPS could be a humane approach. Mammals have a diaphragm and extendable lungs whereas birds have no diaphragm, but have large interconnecting air sacs and their lungs are not expandable. It has been speculated that the response of large mammals (such as farm livestock) may be similar to that of man exposed to ascent to altitude in an unpressurised airplane. This usually results in an uneventful loss of consciousness and death in man. A consortium project (University of Glasgow, University of Edinburgh, Scotland's Rural University College) is currently examining alternatives to CO2 stunning in pigs such as LAPS. This research project is co-funded by DEFRA and the Humane Slaughter Association with TechnoCatch, LLC providing equipment and technical support. LAPS has the potential to improve the welfare in pigs at the time of slaughter and following some proof of principle initial work, studies will examine in detail the behavioral and physiological response of pigs to LAPS.

TechnoCatch, LLC examined the new EFSA Guidance (2013) and its team of advisers designed a multidisciplinary, international research program to fully meet the requirements of the EFSA Guidance. The team was coordinated by Dr David Pritchard, MRCVS, and independent consultant, London, UK; and included Dr Dorothy McKeegan (Scientific Lead), University of Glasgow, UK; Dr Jessica Martin, University of Edinburgh, UK; Professor Malcom Mitchell, Scotland’s Rural University College, UK; Professor Emeritus Yvonne Vizzier Thaxton, Mississippi State University & University of Arkansas, USA, Dr Karen Christensen, Tyson Foods, formerly University of Arkansas, USA; Dr Marien Gerritzen, Wageningen University and Research, NL; Professor Paul Holloway, University of Florida, USA.

7.1.1. McKeegan, D.E.F., Sandercock, D.A., Gerritzen, M.A. 2013. Physiological Responses to Low Atmospheric Pressure Stunning and the Implications for Welfare. Poultry Science, Vol. 92, 858-868.

7.1.2. Vizzier-Thaxton, Y., Christensen, K.D., Schilling, M.W., Buhr, R.J., and Thaxton, J.P. 2010. A new humane method of stunning broilers using low atmospheric pressure. Journal of Applied Poultry Research, Vol. 19, 341 – 348

7.1.3. M. W. Schilling, V. Radhakrishnan, Y. Vizzier-Thaxton, K. Christensen, P. Joseph, J. B. Williams, and T. B. Schmidt (2012)The effects of low atmosphere stunning and deboning time on broiler breast meat quality 2012 Poultry Science 91 :3214–3222 http://dx.doi.org/10.3382/ps.2012-02266

7.1.4. V. Battula, M. W. Schilling, Y. Vizzier-Thaxton, J. M. Behrends, J. B. Williams, and T. B. Schmidt (2008) The Effects of Low-Atmosphere Stunning and Deboning Time on Broiler Breast Meat Quality 2008 Poultry Science 87:1202–1210 doi:10.3382/ps.2007-00454

7.3.1. AVMA Guidelines for the Humane Slaughter of Animals: 2016 Edition https://www.avma.org/KB/Resources/Reference/AnimalWelfare/Documents/Humane-Slaughter-Guidelines.pdf

7.3.2. Meyer R 2015 in Veterinary anesthesia and Analgesia Fifth Edition edited by Lumb and Jones edited by Kurt A. Grimm, Leigh A. Lamont, William J. Tranquilli, Stephen A. Greene, Sheilah A. Robertson, Wiley Pub Ames Iowa Chichester UK

7.3.3  Johnson C L 2014A review of bird welfare during controlled atmosphere and electrical water JAVMA, Vol 245, No. 1, July 1, 2014