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1.
Stunning of poultry is still not solved satisfactorily. This concerns the requirements of animal welfare, meat quality and working conditions in the lairage, stunning and debleeding area. In an investigation of combined CO2-/O2-stunning in a new gas stunning system stress reactions of the animals during the induction phase and stunning effectivity were recorded in 7,000 chicken and 3.825 turkeys. During the induction phase (here: chicken 41 sek./turkeys 25-65 sec.) the animals first staid calm and then showed beak-opening as a consequence of the breathing stimulating effect of CO2. As a further sign of the aversiveness against CO2 the animals showed head shaking and wing flapping. The used settings of gas concentrations and stunning time in the system investigated lead to a very deep stunning resp. Killing of the animals. Therefore the debleeding cut could be performed late (chicken 44-55 sec., turkeys 54-90 sec.) after leaving the system without animals regaining consciousness. The stunning of turkeys with a mixture of CO2 and oxygen is an improvement according to animal welfare requirements because unnecessary pain and suffering, happening very often with electrical stunning, can be avoided. As far as animal welfare in chicken stunning is concerned it must be evaluated if gas stunning means an improvement because stress during the till now relatively long induction phase must be put into relation with comparably lower stress caused by hanging upside down and a fast and safe working electrical stunning unit.  相似文献   

2.
Ever since the middle of the nineteen-eighties electrical stunning of cattle is used in industrial slaughter plants in New Zealand. Today electrical stun boxes operate in export slaughter plants throughout New Zealand. The reversible stun is utilised on the vast majority of slaughtered cattle. The electrical stunning (head only) immediately followed by bleeding is an alternative to ritual slaughter without prior stunning. Throughout the world's islamic community this alternative is widely accepted as Halal.  相似文献   

3.
Slaughter plants have been undergoing radical transformations in recent years due to the need to increase efficiency and incorporate new technologies for the improvement of the infrastructure, animal welfare, and product quality. The aim of this study was to assess the cattle welfare status during the unloading, lairage, stunning, bleeding and quantify bruising incidence at a commercial slaughter plant in the northwest of Mexico. We monitored 8,118 cattle during the unloading, lairage, stunning, bleeding, and carcass bruise incidence. Our results showed that in the unloading stage, 2% of the cattle vocalized, 5% were prodded with an electric goad, and 4% either slipped or fell. In the lairage stage, 12% of the animals vocalized, 80% prodded with an electric goad, and 8% of the animals slipped or fell. In the stunning stage, 10% of the animals vocalized, 67% prodded with an electric goad, and 15% of the animals slipped or fell. Ninety-five percent of the animals were stunned with a single shot, and 51% of the animals were effectively desensitized. Ninety-two percent of the carcasses had some type of bruise. Although the slaughter plant had adequate infrastructure and stringent operational standards, in all of the stages except unloading handling had an impact on the welfare of the animals being slaughtered.  相似文献   

4.
Twelve adult cattle were electrically stunned head-only (400 V, 2.5 A, 50 Hz) behind the ears for four seconds. Within ten seconds of stun initiation, the carotid arteries, jugular veins, trachea and oesophagus were severed. Twenty seconds after the stun initiation, ten animals received an electro-immobilization current (80 V peak, 14.3 Hz, 5 ms square wave, 300 mA) nose to anus for periods ranging from 30-37 seconds. Electroencephalographic (EEG) traces were recorded before and after the stun up until electroimmobilization and at cessation of electro-immobilization by means of implanted electrodes, and animal movement was recorded on videotape. Before the stun, the EEG trace was within a window of sensibility (10-40 microV amplitude). During the stun, the amplitude increased and sometimes exceeded 500 microV. At the end of electro-immobilization, EEG amplitude was less than 10 microV, indicating insensibility. This amplitude was reached in the two non-immobilized animals 57 seconds and 63 seconds after stun initiation. During stunning, the forelegs and hindlegs usually tucked under the animals. Various degrees of foreleg extension then occurred. From about ten seconds post-stun, paddling movements occurred, at which time the EEG trace showed large-amplitude waves characteristic of a stunned animal. During immobilization, the animals stiffened and breathing stopped. After immobilization weak muscle spasms occurred that did not interfere with dressing operations. Non-immobilized animals moved excessively, inhibiting dressing. It is concluded that adult cattle rendered insensible by stunning do not recover sensibility during the stun/throat-cut/immobilization operation and therefore this procedure is humane.  相似文献   

5.
Many small slaughter facilities use head-only electrical stunning to render swine unconscious and insensible to pain before slaughter. Head-only electrical stunning is a reversible procedure that is optimally effective for approximately 15 s after stun completion. In many small North American slaughter plants, the authors have observed hoist speeds that are too slow to achieve a short enough stun-to-bleed interval to maintain insensibility through exsanguination. Unlike many European plants, there is no separate high-speed hoist for pigs and exsanguination on the floor is not condoned. As a result, a 2-stage stunning method was proposed where head-only stunning for 3 s was immediately followed by application of the same stunning wand to the cardiac region of the animal for 3 s while lying in lateral recumbancy. A paired-comparison study was conducted on 89 pigs in a small slaughter facility to compare the head-only method applied for 6 s with the head/heart method. The objective was to evaluate signs of return to sensibility, stun-to-bleed time, blood lactate concentration, muscle pH, drip loss, and fresh meat color to validate the head/heart electrical stunning method for small slaughter plants. Incidence of corneal reflex was not different (P > 0.05) between head/heart (93.8%) and head only (85%) stunning. Nose twitching was more common (P < 0.05) in head only (26.5%) than head/heart (5%) stunning. Head/heart stunning eliminated rhythmic breathing, natural blinking, eye tracking to moving objects, and righting reflex, which were all observed in head-only stunned pigs. Eye tracking to moving objects was observed in 40.8% of head-only stunned pigs. Blood lactate was not different (P > 0.05) between stunning methods (head only: 8.8 ± 0.7 mmol/L, head/heart: 7.8 ± 0.7 mmol/L). Stun-to-bleed time did not differ (P > 0.05; head only: 32 ± 1 s, head/heart: 33 ± 1 s). Mean time to loss of heartbeat with the head-only method was 121 ± 5 s. No heartbeat was observed with the head/heart method. Longissimus thoracis pH, color, and drip loss were not different (P > 0.05) between stunning methods. This study determined that the head/heart electrical stunning method reduces the incidence of signs of return to sensibility without significant effects on meat quality, plant operation speed, or blood lactate concentration. In addition, the head/heart method requires no capital investment for plants that are currently using the head-only method.  相似文献   

6.
78 rabbits of mixed breed and about 3 kg live weight were stunned before slaughter with a commercial spring operated captive bolt apparatus designed for rabbits and water fowl. The following reaction patterns were observed: 1.) Immediate onset of tonic spasm, followed by weak to heavy clonic spasms and/or subsequent relaxation; irreversible loss of corneal reflex and cessation of respiration: effective and irreversible stun tantamount to killing 2.) Same reaction as before except that respiration restarted after 1/2 to 2 min: effective but only temporary stun 3.) Similar reaction as before, but respiration maintained: insufficient stun 4.) Immediate onset of weak tonic spasm; respiration and corneal reflex maintained: insufficient stun. According to this classification 56 rabbits (72%) were killed outright and 18 (23%) temporarily stunned while in 4 (5%) the stun was ineffective. The captive bolt apparatus proved thus to be principally suited for the stunning resp. killing of slaughter rabbits. The best stunning results were obtained with shots into the parietal bone near the sagittal line but not hitting the bone sutures. To achieve this the apparatus has to be placed slightly paramedian on the front as close to the ears as possible. Insufficient stunning results could be blamed on deviating shooting positions. To avoid misses a good fixation of the animal including its head is necessary. Correct application provided the use of penetrating concussion stunners should be preferred to applying a blow to the neck for stunning rabbits.  相似文献   

7.
The objectives of this study were (1) to determine the levels of cortisol (C) and catecholamines (adrenaline, A, and noradrenaline, NA) in lambs (n = 45) at different age/slaughter weight [suckling vs light], in farm (T0), after transport (T1), in the slaughterhouse after lairage (T2) and (2) to study the effect of the type of stunning, electrically vsgas, on C, A and NA values, in both groups of slaughter weight. Levels of C and A at T0 and T1 were similar in both groups (suckling and light), but NA was higher in suckling lambs as in T0 (P < 0.05) as in T1 (P < 0.01). Levels of all hormones were higher in suckling lambs at T2 (P < 0.05, P < 0.001 and P < 0.01, for C, A and NA, respectively). In general, the younger group showed higher values of C, A and NA than the light group after stunning, with significant differences on A and C in the electrically stunned lambs (P < 0.001, P < 0.05 respectively) and on A in the gas stunned group (P < 0.01). Only in the light group, levels of A were higher (P < 0.01) in the electrically than in the gas stunned group. In conclusion CO2 could be a good method to stun lambs because stress indexes were similar to levels found in electronarcosis method.  相似文献   

8.
M. Werner  C. Gallo   《Livestock Science》2008,115(1):94-98
The aim of the present study was to determine, in horses destined to slaughter, the effects of transport, lairage and stunning on some blood constituents related to stress. Twenty one horses culled from a race track due to poor athletic performance, transported weekly to a nearby slaughterhouse were used. Each horse was canulated through venipuncture of the right jugular vein with a central venous catheter which remained permanently until after the exsanguination. Through the catheter, blood samples were taken at 6 sampling times: one hour before loading of the horses, immediately after loading, at the end of the journey, immediately after unloading, after lairage, in the stunning box before stunning and during exsanguination. Blood samples were analyzed for the following variables: plasma lactate concentration, plasma creatine phosphokinase activity (CK), plasma glucose concentration, plasma cortisol concentration and packed cell volume (PCV). Time in the stunning box, number of stunning attempts, presence of return to consciousness signs and time between stunning and sticking were also recorded. The results for pre-mortem variables were: mean time in the stunning box 9 min 48 sec, 85.7% of the horses fell at the first stunning attempt, 57.2% of the horses showed signs of returning to consciousness after stunning and the most frequent interval between stunning and sticking was 1.01 to 2 min. Mean values for the blood variables showed a significant rise (P < 0.05) in the concentrations of lactate, glucose and cortisol, as well as CK activity and PCV during transport. The highest values for these blood constituents were seen before stunning and during exsanguination, except for cortisol concentration, which showed the highest values during the transport process.  相似文献   

9.
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.  相似文献   

10.
In this study the effects of barren vs enriched housing conditions of pigs on their behavior during the lairage period (2-h holding period before slaughter), carcass characteristics, postmortem muscle metabolism, and meat quality were studied. The barren housing system was defined by common intensive housing conditions (i.e., with slatted floors and recommended space allowances), whereas the enriched environment incorporated extra space and straw for manipulation. Salivary cortisol concentrations were measured before transport and at the end of the lairage period. During the lairage period the percentage of time spent walking and fighting by the pigs was registered. Carcass characteristics such as weight, meat percentage, and backfat thickness were determined. At 5 min, 45 min, 4 h, and 24 h postmortem, pH, temperature, and lactate concentrations were determined in the longissimus lumborum (LL) and biceps femoris (BF) muscles. Capillarization of the muscle, mean muscle fiber area, and color and drip loss after 2 and 5 d of storage were determined for both muscle types. Pigs from the barren environment had a significantly higher increase in cortisol from farm to slaughter, but no differences in behavior were observed during the lairage period. Carcass characteristics did not differ between pigs from barren and those from enriched housing conditions. Postmortem lactate formation was significantly lower in LL muscles of enriched pigs at 4 and 24 h postmortem. Capillary density and mean muscle fiber area did not differ between the groups of pigs. The percentage of drip loss at 2 and 5 d after storage of LL muscle samples from enriched-housed pigs was significantly lower than that of the barren-housed pigs. Similar tendencies were found for the BF muscle from pigs kept in an enriched environment, but these were not statistically significant. The housing system did not affect meat color. It is concluded that on-farm improvement of animal welfare by environmental enrichment can also lead to beneficial economic effects after slaughter by improving the water-holding capacity of pork.  相似文献   

11.
1. The objective of this work was to investigate the feasibility of head only waterbath stunning as a means of generating immediate and long lasting unconsciousness while preventing wing flapping and avoiding carcass damage. 2. EEG measurements showed that immersion of the heads of the broilers for one second in a waterbath containing water of conductivity 2 x 5 mS/cm and a 50 Hz electric field of 10 V/cm resulted in immediate unconsciousness, and that increasing the electric field strength extended the duration of unconsciousness. 3. The passage of a 25-30 mA alternating current of frequency 2000 Hz through the broilers' bodies suppressed the wing flapping that followed a stun. 4. When the body current and electric field were applied simultaneously, wing flapping was prevented and EEG signals were suppressed for over 30 seconds indicating that the immediate unconsciousness lasted long enough to facilitate humane slaughter.  相似文献   

12.
1. According to the loading density there is a significant increase of the physical burden (strain) during a transport of pigs to the slaughterhouse. Keeping up minimal requirements (kgs pigs/sqm) the stress reaction decreases and the meat quality becomes better. 2. Each transport produces excitement which can be shown in higher respiratory and heart frequencies. The slaughtering of excited animals shows a higher percentage of carcasses with bad meat quality. Waiting times from at least 2 hours up to a maximum of 4 hours shows that the percentage of carcasses with a better meat quality increases. 3. Handling of animals at the slaughterhouse prior to stunning by dividing the number of pigs into small groups of at least 9 animals is very important especially because it reduces the excitement of the pigs prior to stunning. The stunning results are getting better. Mistakes in handling pigs prior to stunning especially in guiding them to the stunning place usually destroy all positive efforts for optimal transparent conditions and keeping up waiting times after transport. 4. The last step ahead to the stunning equipment. No good solution does exist which makes the pigs willingly do this last step and enter the place where the stunning is performed. This results in the CO2 stunning system itself as well as in the automatic electrical stunning equipment using a restrainer. 5. Stunning with CO2.  相似文献   

13.
Eighteen of 23 red deer (Cervus elaphus) at a deer slaughtering premises were successfully stunned with an apparatus modified from that normally used to stun sheep. The five unsuccessful electrical stuns were associated with poor head restraint and poor head contact by the electrodes. The median stunning current was 0.9 A, and in the majority of cases the duration of stunning was less than 1 second. The signs of the electrically induced epileptiform seizures in the deer were dissimilar to those seen in sheep, cattle and pigs, in that the initial tonic phase was less marked, and of shorter duration. A similar shorter and less obvious tonic phase was noted in four deer shot with a captive bolt pistol. Two animals which were electrically stunned, and bled within 10 seconds, showed no signs of recovery while bleeding. The electroencephalograms of four deer stunned with currents of 1.3 A for a duration of either 0.5 or 1.0 seconds were recorded under more controlled conditions. All four animals developed electroencephalograms typical of an epileptiform seizure. The animals exhibited behavioural reactions similar to the other 18 animals in the trial at the deer slaughtering premises and were rendered unconscious for between 54 and 122 seconds. The electroencephalogram activity amplitude was greater than that recorded immediately before stunning and took between 6 and 9 seconds to build up to maximum value. It is concluded that, providing the heads of deer are adequately restrained, head-only electrical stunning can be incorporated into a humane method of slaughter for deer.  相似文献   

14.
Pigs from three farms were deprived of food for up to one hour, 12 hours or 18 hours before being sent for slaughter. In lairage, the animals' behaviour was monitored, and at slaughter a blood sample was collected and analysed for cortisol, lactate and creatine phosphokinase, potential indicators of stress and physical activity. The carcases were assessed for skin damage as an index of fighting, and rigor in the hind leg as an indicator of stress and/or fatigue. Measurements were also made of cold carcase weight, backfat thickness and liver glycogen concentration. General activity was very high on entry to the lairage pen. Drinking and mounting occurred almost immediately. Fighting developed after an exploratory period, and could last up to 60 minutes. There were large differences in the behaviour of pigs from the three farms. Pigs from farm A fought frequently but showed little mounting activity, whereas pigs from farm C were involved in mounting but little fighting. The period of food deprivation had no effect on average skin damage or rigor score, but the frequency of carcases with the highest scores was different The pigs deprived of food for up to an hour had the lowest incidence of severe skin damage and high rigor scores. Boars had a higher incidence of severe skin damage but a lower incidence of carcases with a high rigor score than gilts. Liver glycogen was almost completely depleted in the pigs deprived of food for 12 and 18 hours and was lower in the pigs deprived for up to an hour than in animals fed immediately before slaughter. The period of food deprivation had no effect on the levels of cortisol, creatine phosphokinase or lactate in the blood.  相似文献   

15.
1. Two separate experiments were carried out in this study. In experiment 1, the effectiveness of stunning broilers, as determined from physical responses, with a 6 mm diameter bolt and an air line pressure of 827 kPa, when fired at 90 degrees (perpendicular to the skull) 110 degrees, 120 degrees and 130 degrees (leaning towards beak) was evaluated. 2. In experiment 2, the effects of perpendicular shooting with two bolt diameters (3 and 6 mm) and two air line pressures (620 and 827 kPa) on spontaneous behaviour, electroencephalogram (EEG) and visually evoked potentials (VEPs) were evaluated in broilers. 3. Only the perpendicular shooting was effective in stunning/killing broilers (n= 10) as indicated by the immediate cessation of breathing and loss of neck muscle tension and eye reflexes. Deviations from the perpendicular shooting failed to stun 5 out of 9 broilers. The perpendicular vs non-perpendicular effect was significant. 4. Shooting broilers with a 3 mm bolt at air line pressures of 620 kPa (n=2) or 827 kPa (n=2) failed stun as indicated by the unaltered physical reflexes, EEG and VEPs. Shooting of two broilers with a 6 mm bolt at 620 kPa resulted in effective stunning and a very rapid recovery of consciousness in one bird and death in the other. 5. Captive bolt stunning of broilers with a 6 mm bolt and air line pressure of 827 kPa resulted in an immediate stun leading to death in all 6 broilers tested. In these broilers, a profound EEG suppression and abolition of VEPs occurred immediately after shooting. 6. It is suggested that the appropriate variables for captive bolt stunning of broilers are a minimum of 6 mm bolt diameter driven at an air line pressure of 827 kPa and a penetration depth of 10 mm.  相似文献   

16.
The objective of the present experiment was to study physiological changes elicited in response to stress in the immediate preslaughter period and to link them to pork quality characteristics. Crossbred, halothane-free pigs (n = 192) were processed in eight groups (24 pigs per group) on various days at one of two commercial processing plants operating different stunning systems (electrical and CO2 stunning in Plants A and B, respectively). In each group, half the pigs were exposed to either minimal or high preslaughter stress. Blood samples were taken at exsanguination, and lactate, cortisol, and catecholamines, as well as blood pH and temperature, were assessed and linked to various longissimus muscle quality attributes. Additionally, muscle pH and temperature were measured 30 min postmortem, and muscle glycolytic potential was determined 22 h postmortem. At both processing plants, high preslaughter stress resulted in higher (P < 0.05) blood cortisol and lactate; however, the effects of preslaughter stress on catecholamines and blood pH were believed to be biased by the different stunning methods employed at the plants. High preslaughter stress increased (P < 0.05) blood temperature at Plant A but not at Plant B. At both plants, high stress increased (P < 0.05) 30-min muscle temperature and decreased (P < 0.05) 30-min muscle pH. Ultimate pH was increased (P < 0.05) and muscle glycolytic potential was decreased (P < 0.05) by high preslaughter stress. At both plants, high stress resulted in inferior pork quality attributes (P < 0.05), including reflectance, electrical conductivity, filter paper moisture, drip loss, and L* value. The effect of stress was greater on water-holding capacity than on pork color, with drip losses increased by 56%. Of all stress indicators measured at exsanguination, only blood lactate was strongly correlated with pork quality attributes. Regression analyses revealed that blood lactate and glycolytic potential accounted for 52 and 48% of the variation in drip loss and L* value, respectively. In combination with high preslaughter stress, high glycolytic potentials were related to increased drip losses. We conclude that high preslaughter stress leads to impaired pork quality, with high muscle energy levels aggravating the negative effects of preslaughter stress. Monitoring stress level by blood lactate measurement in combination with strategies to control muscle energy present at slaughter may help to improve meat quality.  相似文献   

17.
The study aimed to reduce cross-contamination between finishers from Salmonella-positive and Salmonella-negative herds during transport, lairage, and slaughter, thereby reducing the prevalence of Salmonella Typhimurium on slaughter carcasses. In Phase 1 of the study, pigs from Salmonella-negative herds were kept in lairage for 2-4 hours either in clean pens (intervention group) or pens contaminated with Salmonella-infected faeces (control group). All pigs were slaughtered on the same slaughterline, and carcass swabs 24 hours after slaughter revealed a low degree of cross-contamination in the pens: there was no difference in Salmonella-positive carcasses between intervention (1.7%) and control groups (0.8%). In Phase 2, control pigs from Salmonella-negative herds were mixed with pigs from Salmonella-positive herds during lairage for 2-4 hours, while the intervention group still consisted of pigs from Salmonella-negative herds. All pigs were slaughtered on the same line: first intervention, then control. Carcass swabs taken 24 hours after slaughter failed to show a reduction in Salmonella-positive carcasses in the intervention group (4.5%) compared with the originally Salmonella-negative pigs in the control group (3.6%). In pigs from Salmonella-positive herds the occurrence of Salmonella was substantially higher at 10.4%. When the results were corrected for 6 carcass samples found positive with S. Heidelberg on the same day, which was attributed to a transient hygiene failure, only 2.2% of the carcasses in the intervention group were Salmonella-positive. We conclude that even though cross-contamination occurs in the abattoir pens, its importance on the slaughter line may be greater. However, the final results of this study should be awaited to conclude whether separate slaughter of pigs from Salmonella-positive and Salmonella-negative herds should be recommended.  相似文献   

18.
A total of 150 Large White cross Landrace pigs (110-120 kg) of both sexes were used to investigate the effects of three different lairage times (0 h, 3 h, 9 h). Blood samples were collected at exanguination and cortisol, glucose, lactate, muscle enzymes and haematological parameters were determined. Post-mortem measurements of muscle pH were taken at 20 min, 2 h and 24 h from Longissimus thoracis and Semimembranosus. Lairage time showed a significant effect on pH24, internal muscle reflectance using the fibre optic probe (FOP24), red blood cells, neutrophils and lymphocytes, glucose and enzymatic activities. Changes in blood profile and meat quality parameters indicated that three hours of lairage in Spanish commercial conditions may reduce the amount of stress exhibited by pigs at slaughter and better meat quality can be obtained. No lairage or an excessively long lairage period without food may compromise animal welfare and meat quality.  相似文献   

19.
Electroencephalographic (EEG) recordings were made on 34 calves (two days to six weeks old, 30-50 kg) during the slaughter process. The calves, supported in a V-shaped box or polypropylene net, were either head-only electrically stunned (50 Hz, 1.0 A) across the head and allowed to recover, head-only stunned followed by throat cutting or head-only stunned followed by throat cutting and electro-immobilisation. All time intervals were measured from the commencement of the stun. The electro-immobilisation (80 V peak, 14.3 Hz, 5 ms square wave) at 15-26 seconds post-stun was applied through electrodes attached to nose and anus, for periods ranging from 5-60 seconds. The head only stun produced an elevated EEG amplitude of the electroplectic fit which lasted approximately 34 seconds followed by a quiescent period before the EEG amplitude again became elevated above normal. A normal pre-stun pattern was not reached until many minutes had elapsed. Following the stun, the forelegs were usually flexed and then extended, gradually becoming part of the paddling movements commencing as early as eight seconds post-stun. Such movements were taking place while the animal was still stunned. With a head-only stun followed by throat cutting, the electroplectic fit was reduced to about 23 seconds and the amplitude of the EEG fell to about 10 microV after 50-73 seconds and breathing was inhibited for at least 20 seconds after stun commencement. If inadvertently only one carotid was severed, the EEG did not fall as rapidly as when both carotids were cut. The increase in amplitude of the EEG tracings was caused by stunning but the reduced duration of this increase in calves in which the throat was cut, suggests that there is an impairment of recovery of brain function from the moment of cutting and recovery of sensibility is unlikely. In reviewing the criteria of sensibility, we believe that insensibility can be presumed to continue from stun initiation, through the throat cut until the EEG falls below 10/microV provided that there is no resurgence of activity and the EEG amplitude continually falls rapidly enough. By this criteria, calves which are electrically stunned and rapidly exsanguinated remain permanently and irreversibly insensible. The addition of at least 15 seconds electro-immobilisation causes an even more rapid fall in the amplitude of the EEG (<10 microV at 50 seconds) making insensibility more certain as well as abolishing animal movement.  相似文献   

20.
A total of 1,936 pigs were transported through 8 trips (8.4 ± 0.5 hr) from 2 grow-to-finish farms to a commercial slaughter plant, all located in Southern Brazil. On each trip, a sub-sample of each load (36 barrows/load, weighing 118.9 ± 9.8 kg) was randomly allocated into one of the following loading densities during transport: 200 kg/m2 (D200), 235 kg/m2 (D235), and 270 kg/m2 (D270). Behavioral recordings of postures and activities were made during transportation and lairage using video-cameras. At slaughter, blood samples were collected to assess the concentrations of creatine kinase (CK) and lactate. Carcass weights and skin lesion scores were assessed on-line, and meat quality was evaluated in the longissimus thoracis (LT) muscle by assessing pH, color, and drip loss. During transportation, the proportion of animals lying down was higher (P < 0.05) in D200 and D235 groups compared with D270. The proportion of sitting animals during transportation was higher (P < 0.01) in D270 compared with D200. In lairage, D200 and D235 pigs stood more compared with D270 (P = 0.01), while the proportion of lying pigs was higher (P = 0.02) for D270 pigs compared with D200 and D235. The frequency of drinking bouts in lairage was higher (P < 0.05) for D200 group compared with D235 and D270. The levels of CK were lower (P < 0.05) in D200 pigs transported compared with D270. Lesion scores tended to be higher (P = 0.06) in D270 carcasses compared with D200 and D235. A tendency for lower (P = 0.10) pH1 values in the LT muscle of D270 pigs compared with D200 pigs was also found. Based on the results of this study, the application of lower loading densities (≤235 kg/m2) in the truck allows pigs to have sufficient space to rest, travel more comfortably and arrive less fatigued at the slaughter plant.  相似文献   

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