Looks like we've got opposed journal articles, because the posts below disagree with the references above. The bold and italics is mine. The German study is dated now, the studies below are much more up-to-date. Anyone have any tie breaking information?
--------------------------------
Vet Rec. 1988 Apr 2;122(14):325-9.
Cortical function in cattle during slaughter: conventional captive
bolt stunning followed by exsanguination compared with shechita
slaughter.
Daly CC, Kallweit E, Ellendorf F.
Institute of Food Research, Bristol Laboratory, Langford.
Brain function was examined in adult cattle after conventional
captive bolt stunning or shechita slaughter, using eight animals in
each treatment. The times to loss of evoked responses (visual and
somatosensory) and spontaneous activity in the electro-corticogram were
used to determine the onset of brain failure. Captive bolt stunning
followed by sticking one minute later resulted in immediate and
irreversible loss of evoked responses after the stun. Spontaneous
cortical activity was lost before sticking in three animals, and in an
average of 10 seconds after sticking in the remaining five animals. The
duration of brain function after shechita was very variable, and
particularly contrasted with captive bolt stunning with respect to the
effects on evoked responses. These were lost between 20 and 126 seconds
(means of 77 seconds for somatosensory and 55 seconds for visual evoked
responses) and spontaneous activity was lost between 19 and 113 seconds
(mean 75 seconds) after slaughter.
-------------------------------------------------
Journal of Applied Animal Welfare Science
2000, Vol. 3, No. 3, Pages 215-230
(doi:10.1207/S15327604JAWS0303_3)
Penetrating Captive Bolt Stunning and Exsanguination of Cattle in Abattoirs
Neville Gregory
South Australian Research and Development Institute, Flaxley, South Australia, Australia
Frank Shaw
Food Science Australia, Brisbane, Queensland, Australia
Abattoirs
commonly use penetrating captive bolt pistols to stun cattle. Humane
slaughter requires that an animal immediately becomes unconscious and
does not regain consciousness. In this review we consider the concepts
of concussion, unconsciousness, and return to consciousness. We
conclude that an animal effectively stunned with a penetrating captive
bolt pistol, as indicated by the presence of certain signs and the
absence of others, has little possibility of brain function returning.
Appropriate monitoring at all stages between stunning and sticking
would ensure immediate detection and restunning on those few occasions
when brain function was returning. When a captive bolt irreversibly
stuns animals, sticking has no role in terms of animal welfare; its
only function is to relieve the carcass of blood. With effective
initial stunning and subsequent monitoring, specifying a stun-to-stick
interval appears unnecessary. Abattoir surveys have indicated that it
is possible to approximate, or even actually obtain, 100% successful
stunning from a single shot. Furthermore, low prevalence of recovery
follows. Thus, penetrating captive bolt stunning can form part of a
process for the humane slaughter of cattle. This article outlines an
approach to implementing standard operating procedures for checking the
effectiveness of captive bolt stunning.
Looks like we've got opposed journal articles, because the posts below disagree with the references above. The bold and italics is mine. The German study is dated now, the studies below are much more up-to-date. Anyone have any tie breaking information?
Vet Rec. 1988 Apr 2;122(14):325-9.
Cortical function in cattle during slaughter: conventional captive
bolt stunning followed by exsanguination compared with shechita
slaughter.
Daly CC, Kallweit E, Ellendorf F.
Institute of Food Research, Bristol Laboratory, Langford.
Brain function was examined in adult cattle after conventional
captive bolt stunning or shechita slaughter, using eight animals in
each treatment. The times to loss of evoked responses (visual and
somatosensory) and spontaneous activity in the electro-corticogram were
used to determine the onset of brain failure. Captive bolt stunning
followed by sticking one minute later resulted in immediate and
irreversible loss of evoked responses after the stun. Spontaneous
cortical activity was lost before sticking in three animals, and in an
average of 10 seconds after sticking in the remaining five animals. The
duration of brain function after shechita was very variable, and
particularly contrasted with captive bolt stunning with respect to the
effects on evoked responses. These were lost between 20 and 126 seconds
(means of 77 seconds for somatosensory and 55 seconds for visual evoked
responses) and spontaneous activity was lost between 19 and 113 seconds
(mean 75 seconds) after slaughter.
-------------------------------------------------
Journal of Applied Animal Welfare Science
2000, Vol. 3, No. 3, Pages 215-230
(doi:10.1207/S15327604JAWS0303_3)
Penetrating Captive Bolt Stunning and Exsanguination of Cattle in Abattoirs
Neville Gregory
South Australian Research and Development Institute, Flaxley, South Australia, Australia
Frank Shaw
Food Science Australia, Brisbane, Queensland, Australia
Abattoirs
commonly use penetrating captive bolt pistols to stun cattle. Humane
slaughter requires that an animal immediately becomes unconscious and
does not regain consciousness. In this review we consider the concepts
of concussion, unconsciousness, and return to consciousness. We
conclude that an animal effectively stunned with a penetrating captive
bolt pistol, as indicated by the presence of certain signs and the
absence of others, has little possibility of brain function returning.
Appropriate monitoring at all stages between stunning and sticking
would ensure immediate detection and restunning on those few occasions
when brain function was returning. When a captive bolt irreversibly
stuns animals, sticking has no role in terms of animal welfare; its
only function is to relieve the carcass of blood. With effective
initial stunning and subsequent monitoring, specifying a stun-to-stick
interval appears unnecessary. Abattoir surveys have indicated that it
is possible to approximate, or even actually obtain, 100% successful
stunning from a single shot. Furthermore, low prevalence of recovery
follows. Thus, penetrating captive bolt stunning can form part of a
process for the humane slaughter of cattle. This article outlines an
approach to implementing standard operating procedures for checking the
effectiveness of captive bolt stunning.
-----------------------------------