Because of the growing body of evidence in the published literature that exposure to carbon dioxide (CO2)
causes more than momentary pain and distress in animals, and the
first-hand experience of witnessing the suffering, and agonal
vocalizations of animals undergoing death by CO2, Little Blue Society (LBS) STRONGLY OPPOSES the use of CO2
in all forms e.g. gas compressed in cylinders, and carbon dioxide gas
generated by other methods such as from dry ice, fire extinguishers, or
chemical means (i.e. antacids) to kill any animals.
After
numerous complaints from the public about the Santa Clara County Vector
Control's approach and methodology in dealing with coyotes and other
so-called “nuisance” wildlife. And learning that they used a metal gas
chamber with industrial strength carbon dioxide gas to suffocate the
animals, in April of 2005, Little Blue Society designed a program and
submitted a proposal to the Vector Control Agency asking them to
transition from carbon dioxide gas to the more humane lethal injection.
After
a year of negotiations with the Agency and with the help of Supervisor
Pete McHugh, the Vector Control Agency transitioned from using CO2 to
the more humane lethal injection to dispatch "nuisance" wildlife.
This change went in to effect January 1, 2006.
OUR reasons for opposing CO2: This
includes compressed carbon dioxide (CO2) gas in cylinders and carbon
dioxide generated by other methods such as from dry ice, fire
extinguishers, or chemical means such as antacids.
1. The AVMA report provides information on CO2
use as a euthanasia agent, but its summary of the available literature
is inadequate. It does not address some key issues raised by the
literature or by differences in common laboratory practice, and its
recommendations are vague at best.
2. The AVMA recommeded concentration and method of CO2 euthanasia does NOT meet it’s own standards for humane euthanasia:
a. euthanasia techniques should result in rapid unconsciousness
b. followed by cardiac or respiratory arrest and ultimate loss of brain function.
In addition, the technique should minimize any stress and anxiety experienced by the animal prior to unconsciousness.
The
1986 and 1993 AVMA reports on euthanasia cautioned against the use of
decapitation because it was found that EEG activity continued for an
average of 13.6 seconds in the decapitated heads. With the AVMA
recommended concentration and method of CO2 euthanasia, the time until
unconsciousness ranged from 10 seconds to 4 minutes in published
studies. Therefore the potential for 13.6 seconds or more of stress or
distress in CO2 euthanasia is high even by the AVMA’s own standards for
euthanasia.
3. CO2 has actually been used as a stimulus in
studies that examine pain responses in animals (Barbaccia et al., 1996;
Thurauf et al., 1991) as has been done in humans.
4. All mammals
have chemical receptors in their lungs (intrapulmonary chemoreceptors,
or IPCs) that are acutely sensitive to carbon dioxide.
In
a seminar presented at the US Department of Agriculture on December 16,
2004, Dr. Mohan Raj, Senior Research Fellow in the Farm Animal Division
of the School of Clinical Veterinary Science at the University of
Bristol in England, described the effects of CO2 on the body. CO2
induces breathlessness – a subjective distress in breathing known as
dyspnea. According to Dr. Raj, dyspnea in both birds and mammals
“activates brain regions associated with pain and induces an emotional
response of panic.”
