Read the entire report: Doden van wrakke beesten op het bedrijf
Sick and/or injured farm animals pose a problem because it is forbidden to transport both categories of animals live to the slaughterhouse. This means they must be killed on site. All healthy animals that are injured through an accident can still be approved for human consumption by a vet. In order to limit unnecessary suffering the farmer is lawfully permitted to use a penetrating captive bolt for euthanasia of pigs, cattle, sheep and goats. However, this is an aesthetically displeasing method to most farmers. Alternative methods have been investigated from the point of view of a humane death.
Dutch ministry for agriculture, nature management and food safety (LNV) has commissioned this review of the available options to farmers for on-farm euthanasia of cattle, pigs, sheep and goats without the intervention of a veterinarian.
In this report a number of euthanasia methods for sick and/or injured animals are discussed and evaluated. The euthanasia methods included are physical and electrical methods, (mix of) gas, lethal substances and new (experimental) methods. These methods are evaluated in relation to: animal welfare, effectiveness, efficiency, aesthetic consideration of the operator (farmer), skills required, risks and restrictions.
The penetrating captive bolt in combination with exsanguination or insertion of a pithing rod (c. 15cm) into the cavity is the most effective and efficient of the physical methods used on pigs, cattle, sheep and goats. Pithing is not allowed for animals entering the human consumption chain and therefore only acceptable for animals that are to be destroyed. In addition, emotional stress can pose a difficult restraint on those performing the act. This can be due to physical contact with the animal and the force of impact on the skull of the animal. This method can be difficult to execute with active and larger animals and animals should be adequately restrained. It is not recommended for young animals and can be ineffective in adult pigs.
Electrocution is the major electrical method applicable. It is a humane, effective and efficient method. Disadvantages include violent tonic muscle cramps which are aesthetically displeasing. A recent development for on-farm electrocution has been the introduction of the SPEE mobile unit.
Use of CO2 is the most suitable gaseous method. This method results in rapid unconsciousness, is analgesic and anesthetic. The gas is inexpensive and dosage is exact. Furthermore, it is non- flammable, non-explosive, and poses minimal hazard to personnel when used with properly designed equipment. However, there are problems with the CO2-method which are: that CO2 is heavier than air, incomplete filling of a chamber may permit animals to climb or raise their heads above the higher concentrations and avoid exposure, high concentrations of CO2 are distressful to the animals due to irritation of the mucous membranes and eyes. Use with cattle and small ruminants would seem possible but as yet to be verified.
Injection of lethal solvents is the most reliable method of performing euthanasia. However this method is not suitable for on-farm application. This method requires supervision by a veterinary surgeon and in practice often results in an unnecessary delay leading to a prolongation of the suffering of the sick or injured animal.
Use of water or CO2 enriched foam is a relatively new method with potential. At present research in America involves large groups of poultry and one study involving piglets. Further research will have to be performed on larger and differing types of animals in variable types of containers. The foam method scores impressively well on animal welfare, effectiveness, efficiency, aesthetic acceptance, skill requirements and safety of operation.
Live weight up to 25 kg: Captive bolt accompanied by exsanguination (or insertion of a pithing rod for those animal to be destroyed) is the preferred method, an adequate restraining method and the emotional stress of the operator present problems for popularity of this method. Research into a safe and user friendly electrocution method is recommended.
Live weight above 25 kg: Euthanasia with a captive bolt in combination with exsanguination (or a pithing rod for those animals to be destroyed) is the preferred method. Under correct restraining
conditions and with due consideration of user safety, electrocution is also acceptable. Carbon dioxide and foam are potential alternatives for on-farm usage.
Generally speaking, use of the captive bolt method combined with exsanguination (or for destruction animals insertion of a pithing rod with plug to prevent spilling of cranial tissues) or gunshot (under permit) are the only practical methods without intervention of a veterinarian. Electrocution is effective but is a difficult and potentially dangerous method to perform on larger (dairy and beef cattle) species. Special attention should be given to the euthanasia of calves and bulls. The captive bolt method and use of barbiturates (veterinary assistance) are acceptable methods for both calves and bulls. Euthanasia of bulls can be difficult due to their size and the thickness of their skull.
Sheep and goats:
Use of a captive bolt (or gunshot) or concussion accompanied by exsanguination (or insertion of a pithing rod for animals to be destroyed) are the approved methods for on-farm euthanasia of sick or injured sheep and goats.
Treatment of injured or sick animals is strongly influenced by legislature and economics.
Use of a captive bolt accompanied by exsanguination (or insertion of a pithing rod for animals to be destroyed), electrocution and carbon dioxide are accepted methods for on-farm euthanasia without intervention of a veterinarian.
Use of barbiturates always requires veterinary assistance.
Although nitrogen and argon are effective methods there are more welfare friendly methods. Use of foam is potentially welfare friendlier. However, there is little information available concerning the use of foam for the euthanasia of pigs, cattle and small ruminants.
A rapid response is essential to animal welfare when choosing an acceptable method of euthanasia. The choice to involve a veterinarian is also important and has consequences for animal welfare. The extra fees involved greatly influence the choice of the farmer together with any personal aversion towards killing animals. However, euthanasia methods performed by a veterinarian are welfare friendly and more aesthetically acceptable to the farmer. It is suggested to investigate the possibilities for financial compensation for additional costs of on-farm euthanasia with veterinary assistance. This to help those farmers with aesthetical problems regarding the performance of certain methods of euthanasia and to reduce animal suffering.
Further research and development of a practical, effective, efficient and safe method for on-farm euthanasia is essential.
- Further development of a plug or cap (preferably made of biodegradable material) for pithing ofcattle.
- Further research into the effective combinations of CO2 and O2 is required for pigs (25 tot 115 kg).
- Further research should be performed into foam as an alternative to CO2 for pigs. Present resultsindicate that foam is potentially less discomforting to the animal than the CO2-method.
- Research and development of a CO2 method for usage by all species on-farm.
- Additional attention should be given to operational safety when using the CO2-method in confinedspaces alongside measurement and control of mixtures of CO2/O2 and a correct level of humidity.
- Research and development of a safe, handy, effective and efficient on-farm euthanasia methodSimilar to the SPEE mobile unit recently developed in Canada.
- Improvement of equipment for restraining animals when using a captive bolt.
- Research and development of a method of collection and disposal of blood.
- Research and development of a handy and safe method for foam euthanasia on-farm. Possiblyusing a flexible on-farm system with PVC (disposable?) sheeting for use on individual animals ofall size.
- Investigation of the possibilities for financial compensation of farmers for veterinary assistancewith on-farm euthanasia of sick or injured animals.