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Presentation anoxia eng

  1. Anoxia Total absence of oxygen as the principle of the N2GF technology For more information:
  2. Index Part 1 Anoxia Part 2 Killing and slaughter within the European framework Directive EU 1099/2009 Part 3 Killing and the slaughter of animals using nitrogen foam Part 4 Research projects Part 5 Conclusions For more information: 2
  3. Part 1 Anoxia For more information: 3
  4. Anoxia, Hypoxia and Hemoglobin • Anoxia is the condition characterized by complete absence (or almost complete absence) of oxygen supply to the brain • Hypoxia is the condition is characterized by insufficient oxygen supply to the brain • Hemoglobin protein in red blood cells which plays a crucial role in the transportation of oxygen and other gasses throughout the body For more information: 4
  5. Five types of Anoxia • Hypoxemic anoxia – high altitude – Hypoxemic anoxia can happen during deep sea diving or at high altitude, when the oxygen pressure outside the body is so low that hemoglobin in the red blood cells is unable to absorb sufficient oxygen. • Anemic anoxia - accident – Anemic anoxia results from a decrease in the amount of hemoglobin in the blood, which reduces the ability to get oxygen to the tissues, caused for instance by blood loss (hemorrhage) • Affinity anoxia – blood failure – Affinity anoxia involves a defect in the chemistry of the blood such that the hemoglobin can not release oxygen • Stagnant anoxia – heart disease – Stagnant anoxia occurs when the blood flow is blocked, although the blood and its oxygen-carrying abilities are normal • Histotoxic anoxia – narcotics and alcohol – Histotoxic anoxia can also be caused by exposure to narcotics, alcohol etc. For more information: 5
  6. The function of hemoglobin Hemoglobin plays a crucial role in the transport of gasses: • Hemoglobin is the iron- containing oxygen-transport metalloprotein in the red blood cells of all vertebrates • Hemoglobin in the blood carries oxygen from the respiratory organs (lungs) to the rest of the body where it releases the oxygen For more information: 6
  7. Never heard about Anoxia? • In a plane you are instructed what to do in case the cabin pressure drops .. • In case you would climb the Mount Everest, you need additional oxygen, unless you are a Sherpa .. • In case you are diving, you are instructed what to do when you dive below 30 meters .. For more information: 7
  8. So, if oxygen isn’t transported to the lungs, what kind of gasses are transported instead? – Oxygen must be present in every breathing gas because it is essential to the human body's metabolic process – As the altitude increases (from > 2,400 meter) atmospheric pressure decreases, oxygen levels drop – At 30 meter below sea-level, the pressure raises to the level of 4x the normal atmosphere, leading to higher CO2 and lower Oxygen levels. – Decrease of the oxygen level in the blood leads to relative increase of the nitrogen concentration inhaled, resulting in Hypoxic Anoxia – In the medical literature, the effects of exposure to high concentrations of nitrogen is described as Nitrogen Asphyxiation For more information: 8
  9. Nitrogen Asphyxiation and its effects • Nitrogen asphyxiation is a medical condition in which a person dies from hypoxemic anoxia because the nitrogen concentration in his body is too high • When such asphyxiation begins, it only takes several breaths until it affects the body’s oxygen supply: 1 minute of nitrogen exposure may cause a person to fall unconscious and die in less than 10 minutes • Until nitrogen exposure reaches a dangerous level, most persons don’t feel stress or pain. Dying from high level nitrogen happens without warning or immediately noticeable effects, unlike when a person dies from carbon monoxide or carbon dioxide asphyxiation (they typically will become dizzy and feel pain before dying). For more information: 9
  10. Example: Nitrogen asphyxiation and diving • Underwater, a diver must deal with two major issues: pressure and temperature. Pressure affects the amount of nitrogen and oxygen gases that dissolve in the blood and tissues • Atmospheric air is a mixture of 21% oxygen and 78% nitrogen. When a person inhales air, the body does nothing with the nitrogen: it only consumes the oxygen and replaces some of it with carbon dioxide • When a diver descends under the water, the pressure on his body increases, so more nitrogen and oxygen dissolve in his blood. Most of the oxygen gets consumed by his tissues, but the nitrogen remains dissolved • When a diver reaches depths of about 30 m or more, he experiences a feeling of euphoria called nitrogen narcosis: the nitrogen partial pressure reaches high levels, causing the replacement of oxygen by nitrogen in the blood • Nitrogen narcosis can impair the divers judgment, make him feel relaxed or even sleepy • Narcosis comes on suddenly and without warning and when its not detected by a buddy diver, it leads to drowning of the diver For more information: 10
  11. Part 2 Killing and slaughter within the European framework Directive EU 1099/2009 For more information: 11
  12. Killing and slaughtering animals According to Directive EU 1099/2009 • Directive EU 1099/2009 is valid for all situations where animals are killed or slaughtered: – slaughtering of animals at the slaughter house – mass culling during outbreak situations – Killing of sick and crippled animals on the farm • Basic principle: manually killing of animals is not allowed as primary killing method • Only 4 general types of killing techniques are allowed For more information: 12
  13. General types of killing techniques (1) 1. Mechanical methods – Penetrative captive bolt device – Non-penetrative captive bolt device – Firearm with free projectile – Maceration – Cervical dislocation – Percussive blow to the head 2. Electrical methods – Head-only electrical stunning – Head-to-Body electrical stunning – Electrical waterbath For more information: 13
  14. General types of killing techniques (2) 3. Gas methods (hypoxia, hypoxemic anoxia, anoxia) – Carbon dioxide at high concentration – Carbon dioxide in two phases – Carbon dioxide associated with inert gases – Inert gases – Carbon monoxide (pure source) – Carbon monoxide associated with other gases 4. Other methods – Lethal injection (T61) For more information: 14
  15. Category 3: Gas methods A. Hypoxia – CO2 A. Hypoxemic Anoxia – CO2 + Argon A. Anoxia – Nitrogen For more information: 15
  16. A: Hypoxia • Most common gas method: Carbon dioxide • CO2 in high concentration • minimum concentration for poultry: > 40% • Minimum concentration for pigs: > 80% • Applied in various situations • Containers • Pits • Tunnels • Sealed-off buildings • Various forms • Compressed gas in Bottles • Liquid gas in bulk tanks • Dry ice For more information: 16
  17. Hypoxia and the effects on animals • Animals are placed in a room (container/pit/tunnel or in a sealed off building) that is flooded with CO2 that is heavier than air and cold (the temperature of solid CO2 -dry ice- is -78C) • With the raise of the CO2 level, the oxygen level in the room is deprived • The animals notice that they are dying • The animal is slowly but steadily confronted with lack of oxygen the animals react before being unconscious by head shaking (heavy breathing) and convulsions (lack of control over their nerve system) • Some animals react to the raising level of CO2 by withholding their breath as long as possible or try to climb to the highest point in the room • The animals die by the effects of hypoxia For more information: 17
  18. B: Hypoxemic Anoxia • Most common gas combination: Carbon dioxide + Argon • Mixture of different gasses • minimum concentration for poultry: < 40% CO2 • Minimum concentration for stunning pigs: > 30% CO2 within 7 minutes max • Minimum concentration for stunning poultry: > 30% CO2 within 3 minutes max • Applied in various situations • Containers • Pits • Tunnels • Sealed-off buildings • Various forms • Compressed gas mixtures in Bottles • Liquid gas mixtures in bulk tanks For more information: 18
  19. Hypoxemic Anoxia and the effects on animals • Animals are placed in a room (container/pit/tunnel or in a sealed of building) that is flooded with a mixture of CO2 + Argon • In some cases, additional oxygen is added in the first minute to stimulate the animals to maintain their breathing • The animals notice that they are dying • Like with pure CO2, the animal is slowly but steadily confronted with lack of oxygen. The animals react before being unconscious by head shaking (heavy breathing) and convulsions (lack of control over their nerve system) • Because of the gas mixture and the lower concentration of CO2, the lungs are filled with a high concentration of Argon • The animals die by the effects of hypoxic anoxia For more information: 19
  20. C. Anoxia • Techniques based on the exposure concentration of more than 95% nitrogen – Applied in gas chambers floated with high concentrations of nitrogen – Applied in high expansion foam: the N2GF Method For more information: 20
  21. Anoxia and the effects on animals • Animals are placed in a room (container/pit/tunnel or in a sealed of building) that is flooded with gas foam, containing a concentration of >95% Nitrogen • The reaction of the animal to being submerged in foam is minimal • The total absence of oxygen stays unnoticed • The animals do not notice that they are dying • Unlike hypoxia and hypoxic anoxia, the animals don’t react by head shaking or perform convulsions prior to their unconsciousness • After the animals are unconscious, their body reacts with convulsions caused by the lack of control in the nerve system • The animal dies after being submerged in the foam for 1,5 to 2 minutes For more information: 21
  22. The three slaughter principles compared • Hypoxia and Hypoxic anoxia methods: – Large quantities of gas are needed to reach the gas level needed to slaughter/kill the animals – During the process of filling the room with gas, the animals notice that the oxygen level slowly but steadily deprives – Animals react prior to reaching the state of unconsciousness and their reaction on the presence of CO2 (or a combination of CO2 and Argon) • Anoxia methods: – Only a fraction of nitrogen (compared to CO2/combination of CO2+Argon) is needed to create an atmosphere of >95% nitrogen – The animals don’t notice that they are in the process being killed or slaughtered – The animals are killed without any additional stress or pain caused by the slaughter process For more information: 22
  23. Part 3 Killing and slaughtering animals using nitrogen foam For more information: 23
  24. Directive EU 1099/2009 on slaughter by Anoxia The European Union described Anoxia as an accepted gas method (category 3) for the slaughter of poultry and pigs: • ANNEX I - LIST OF STUNNING METHODS AND RELATED SPECIFICATIONS (as referred to in Article 4) CHAPTER I - Methods – table 3 – under 4: • Name: Inert Gas • Description: Direct or progressive exposure of conscious animals to a inert gas mixture such as Argon or Nitrogen leading to anoxia. The method may be used in pits, bags, tunnels, containers or in buildings previously sealed • Conditions of use: Pigs and poultry – slaughter - depopulation and other situations For more information: 24
  25. Animals and nitrogen foam? • Animals hardly show any stress reaction when they are submerged into the foam: – Touching the foam does not hurt – Nitrogen is odorless and tasteless – Foam is colorless • As soon as the head of the animal submerges, it is exposed to a mixture of > 95% nitrogen and <5% oxygen • The first 20 – 25 seconds after being submerged, the animals still don’t notice the absence of oxygen – They maintain their normal breading – They don’t show any muscle contractions • After 20 to 25 seconds, the animals renders unconscious, resulting in the start of the muscle contractions • After 1 to 1,5 minutes, the high concentration of nitrogen in the blood produces heart failure and mortality. For more information: 25
  26. Description nitrogen foam equipment The standard equipment is attached to the wall and consists of: 1. A nitrogen gas cylinder, including hoses and a regulator 2. A pressure vessel for water and soap mix, including water hoses 3. A foam nozzle in which nitrogen and the water/soap solution are mixed 4. Measuring and control equipment to monitor the gas concentration and temperature 5. A standard barrel or container that is filled with the nitrogen gas foam. For more information: 26
  27. Components Foam nozzle Water and foaming agent Nitrogen High expansion foam For more information: 27
  28. Benefits for farmers • The nitrogen gas foam method is easy to integrate into procedures on the farm, and given the absence of unnecessary pain and suffering, it is the most humane killing method available • Both the initial investment and operating costs are very low • Stunning and killing of animals (pigs and poultry) by anoxia is accepted according to the EU directive EU 1099/2009 • The direct involvement of the operator performing the killing of the animals and the effect on him are minimized: low risk of error or failure - minor psychological stress - low physical load • The method is safe. The operator needs only to assure that his nose and mouth are not in direct contact with the gas foam. For more information: 28
  29. Simplified description of the standard procedure to kill animals with nitrogen gas foam The operator starts the procedure to produce the nitrogen foam: • controls water and soap in the pressure vessel - checks gas reserves in the nitrogen bottle - starts the foam production - places the cadaver barrel below the foam nozzle - controls temperature and nitrogen concentration in the foam • makes his rounds through the stables and selects weak and sick animals • removes these animals from the stable and transports them to the cadaver barrel • allows the animals one-by-one carefully through the top layer of the nitrogen foam into the barrel at intervals of 2 minutes • After all sick and weak animals are killed, the the cadaver barrel is closed. The nitrogen foam dissolves completely in the course of time and the concentration of nitrogen in the barrel easily disappears into the atmosphere. For more information: 29
  30. Special features • Simplicity: control, cleaning and disinfection • Cost effective: Low initial investment. Operational costs are very low: only water, soap and nitrogen • Stability of the foam: upper layer of foam (at least 40 cm) ensures that the concentration of nitrogen that is located beneath the foam layer remains high, in spite of the convulsions of the animal. The nitrogen can not escape. Even during the time that the animal falls through the upper foam layer, the concentration of nitrogen remains intact • Safety: nitrogen is an atmospheric gas - non toxic - safe to transport - the soap has no adverse effects on humans and the environment • Animal welfare: animal dies within 1.5 to 2 minutes as a consequence of the absence of oxygen For more information: 30
  31. Part 4 Research projects Opinion of leading animal scientists on Hypoxia and anoxia as slaughter technique For more information: 31
  32. Anoxia Scientific research projects Overview resent research projects (from 2006 until today) on Anoxia and slaughter: • Dr. Marien Gerritzen (Anoxia caused by nitrogen foam) • Dr. Dorothy McKeegan (Anoxia caused by nitrogen foam) Overview resent research projects on Hypoxemic anoxia: • Dr. Mohan Raj (Hypoxemic anoxia by a gas mix of CO2 and argon) For more information: 32
  33. Dr. Marien Gerritzen WUR University of Wageningen Summary, page 11: ‘The use of high expansion gas-filled foam containing CO2 or an Anoxic gas such as Nitrogen presents a feasible alternative delivery method of hypercapnic or anoxic killing, because as the foam envelopes the bird, oxygen will be effectively eliminated and or carbon dioxide will be effectively presented and birds will die by hypercapnic-anoxia or by anoxia.’ For the full text of the report, visit For more information: 33
  34. Dr. Dorothy McKeegan University of Glasgow, College of Medical, Veterinary & Life Sciences Presentation: Gasfoam - a humane agent? (Oct ‘11), conclusions, page 10: ‘Collectively, the results show that anoxic foam has the potential to be a reliable and humane method of emergency killing for poultry.’ For the full text of the report, visit For more information: 34
  35. Dr. Mohan Raj Bristol University, Bristol Veterinary school HSUS Report: The Welfare of Birds at slaughter - Conclusions - page 8: Comparing electrocution and hypoxemic anoxia using a mixture of CO2 and Argon: ‘After a comprehensive review of the scientific literature, the Scientific Panel on Animal Health and Welfare, an official advisory body to the European Commission, (EFSA) stated: Since welfare is poor when the shackling line and water bath electrical stunning method is used, and birds are occasionally not stunned before slaughter, the method should be replaced as soon as possible. At present, the inert gas stun/killing method is the best alternative.’ For more information: text of the report, visit For the full 35
  36. The technique behind the N2GF method The N2GF technique is based on the principle of Anoxia: – High expansion foam bubbles are created, using a nozzle – The water/soap mix is composed by 95% water and 5% soap – The foam bubble is filled with >95% nitrogen – The animals are covered with a layer of foam – Form one moment to the other, the animal is confronted with the total absence of oxygen without noticing – The animal stays completely calm and doesn’t show any convulsions until its unconscious. From that moment on, the convulsions start – After being unconscious, the animal dies, caused by Anoxia For more information: 36
  37. scientific research based on applying the nitrogen foam technique • Since January 2013, the research on applying the technique is conducted at the Pig Innovation Center VIC Sterksel, part of WUR Wageningen University in Holland • The research concentrates on how the technique can be applied as general technique on pig and poultry farms • Following the results, the research will be expanded to the possible application on other animal species • Based on the results, special tools will be developed and tested so that the technique can be applied easily within the daily routines on the farm • The introduction will be completed by an online and vocational training module, including certification for the users For more information: 37
  38. Part 5 Conclusions For more information: 38
  39. Conclusions • The gas foam technique is the only universal killing technique, because it is based purely on Anoxia • Killing and slaughtering with gas foam does not create additional stress or pain • The influence of humans is minimalized using gas foam • Gas foam is efficient and (cost) effective and cheap to apply • Gas foam can be applied on single (sick and injured) animals on the farm, as well as to large numbers of animals during outbreaks of diseases For more information: 39