| Literature DB >> 35203199 |
Jan Hultgren1, Katrin J Schiffer1, Jakub Babol2, Charlotte Berg1.
Abstract
Transporting cattle from farm to slaughterhouse is often stressful for the animal, which can impair the meat quality. With the gunshot method, the animal is stunned with a rifle shot while together with familiar herd members in their home environment, exsanguinated and transported to a nearby slaughterhouse. Aiming to assess the consequences for animal welfare and food safety, 20 Hereford steers aged 18-54 months were shot with .22 Magnum ammunition from an elevated position and distance of 6-12 m. Each time, only one out of four to seven animals in a 16 × 10 m corral was shot. Dressing was done on farm. Based on the animals' behaviour and blood concentrations of cortisol, glucose and lactate, stress levels before shooting were low. Eleven animals were deeply stunned, the consciousness of seven others was ambiguous, and two were poorly stunned. Two animals were reshot. The bleed-out was satisfactory for all animals, and little or no faecal contamination was found on the carcasses. We conclude that the gunshot method is applicable to large beef steers while maintaining a satisfactory level of animal welfare and food safety, provided that the necessary conditions can be attained.Entities:
Keywords: brain haemorrhage; on-farm slaughter; rifle; slaughter hygiene; steer; stun quality
Year: 2022 PMID: 35203199 PMCID: PMC8868530 DOI: 10.3390/ani12040492
Source DB: PubMed Journal: Animals (Basel) ISSN: 2076-2615 Impact factor: 2.752
Figure 1Cattle in the stun corral before gunshot in Sweden, 2020, seen from the shooter’s position 2.9 m above the ground. Photo courtesy of Anne Larsen.
Figure 2Examples of theoretical shooting distances and impact angles to the forehead at different heights of the rifle and animal during gunshot of cattle in Sweden 2020. The grey triangle represents the animal’s head.
Figure 3The carcass being hoisted from the trailer and taken to the slaughter premises (in the background) after on-farm gunshot and exsanguination in Sweden 2020. The feet were covered with protected plastic bags. Photo courtesy of Anne Larsen.
Figure 4The carcass being placed on a wheeled cradle in the doorway of the on-farm slaughter premises, before removal of hide, head and feet. Photo courtesy of Anne Larsen.
Protocol for the assessment of stun quality, following gunshot, of cattle in Sweden, 2020.
| Sign | Type a | Type b | Type c |
|---|---|---|---|
| Posture | Immediate collapse | Delayed or gradual collapse | Incomplete or transitory collapse |
| Kicking after collapse | No kicking | Uncoordinated or slight kicking | Forceful and coordinated kicking |
| Kicking at hoisting a | No kicking | Uncoordinated or slight kicking | Forceful and coordinated kicking |
| Righting reflex b at hoisting a | No movements | Head lifted briefly once during first 20 s | Body curved or head lifted repeatedly or persistently |
| Movements at skin opening for sticking | No movements | Twitching a little | Forceful kicking, lurching or wriggling |
| Movements at sticking | No movements or slight twitch | Twitching, kicking, or slight head movement | Forceful kicking, lurching or wriggling |
| Tail tension | Relaxed | Unclear or slight movements | Clear repeated movements |
| Ear tension | Completely relaxed | Unclear | Stiff or angled |
| Tongue tension | Relaxed, hanging out of mouth | Not visible (in mouth) | Stiff, twisted or moving |
| Eye direction and movements | Wide open, forward, still | Rotated, showing sclera or nystagmus | Directed towards objects |
| Blinking | No spontaneous blinking | Single blink directly after shooting | Repeated blinking |
| Corneal reflex c | No corneal reflex | Corneal reflex directly after shooting | Corneal reflex at hoisting a |
| Breathing | No breathing | Single breath or sigh | Rhythmic and regular breathing |
| Vocalization | No vocalization | Single sigh | Mooing, panting, moaning or bellowing |
a During hoisting or while hanging hoisted before sticking. b Reflexive movements that correct the orientation of the head or body when it is taken out of its normal upright position. c Reflexive eye blinking upon touching of the cornea.
Figure 5Frontal view of the head showing the different distances measured at dissection following gunshot of cattle in Sweden, 2020. The grey and black dots represent the intended target and an (imaginary) bullet entry point, respectively.
Time intervals between different events during stunning of cattle with the gunshot method in Sweden, 2020.
| Time Interval |
| Mean | Minimum | Median | Maximum |
|---|---|---|---|---|---|
| Entry a to start of recording, min | 18 b | 46.2 | 20.7 | 43.0 | 89.3 |
| Entry a to shot, min | 18 b | 55.5 | 22.5 | 57.0 | 90.6 |
| Start of recording to shot, min | 20 | 9.76 | 1.32 | 5.72 | 33.9 |
| Shot to sticking, min | 20 | 1.68 | 0.82 | 1.66 | 2.70 |
| Shot to exit c, min | 20 | 0.55 | 0.28 | 0.44 | 1.23 |
| Entry a to exit c, min | 18 b | 56.0 | 23.7 | 57.4 | 91.4 |
a When the animals entered the corral. b The time of entry to the corral was not recorded for animals #1 and #2. c When the remaining animals left the corral.
Frequency of different animal behaviours a in the stun corral at gunshot of cattle in Sweden 2020; n = 20.
| Behaviour | Mean | Min. | Median | Max. |
|---|---|---|---|---|
| Walking b | 3.46 | 0.4 | 2.25 | 9.8 |
| Listening | 2.50 | 0 | 1.70 | 6.8 |
| Sniffing with head raised | 0.398 | 0 | 0.171 | 2 |
| Exploring | 2.12 | 0 | 1.51 | 10 |
| Other behaviour c or inactive | 2.41 | 0.5 | 2.45 | 7 |
| Any of the recorded behaviours | 10.9 | 3.43 | 8.73 | 27.4 |
a Number of times the behaviour was seen divided by number of animals in corral from start of recording to exit from corral. b Taking one or several steps forward or backward, after standing still. c Running, turning around, butting, vocalising, flehmen, defecating or urinating.
Measures of head dimensions and bullet tracks recorded at head dissection after gunshot of cattle in Sweden, 2020; n = 20.
| Measure a | Mean | Minimum | Median | Maximum |
|---|---|---|---|---|
| Crown to muzzle (a), cm | 48.3 | 43.5 | 47.5 | 58.0 |
| Between lateral eye corners (b), cm | 24.7 | 22.0 | 24.3 | 28.0 |
| Between medial eye corners (c), cm | 21.0 | 18.0 | 21.0 | 24.0 |
| Crown to medial eye corner (d), cm | 26.2 | 23.5 | 25.8 | 30.0 |
| Medial eye corner to muzzle (e), cm | 25.8 | 22.0 | 25.8 | 30.0 |
| Vertical deviation b (g), mm | −24 | −80 | −33 | 51 |
| Horizontal deviation c (h), mm | −4 | −35 | −5 | 24 |
| Bullet hole diameter, mm | 7 | 4 | 6 | 14 |
| Bone thickness in bullet hole, mm | 10 | 3 | 4 | 36 |
| Angle of shot to head d, degrees | 81 | 70 | 81 | 92 |
| Penetration depth, cm | 10.0 | 2.8 | 10.3 | 14.5 |
a Letters within parentheses refer to Figure 5. b Vertical distance between the intended target to the actual hit location, caudally (towards the crown). c Horizontal distance between the intended target to the actual bullet entry point, towards the animal’s left side. d Measured at bullet entrance, rostrally to the entry point (towards the muzzle).
Measures relating to carcass dressing and food safety at gunshot of cattle in Sweden, 2020; n = 20 a.
| Measure | Mean | Minimum | Median | Maximum |
|---|---|---|---|---|
| Time for bleeding, min | 8.1 | 5.0 | 7.7 | 11.4 |
| Time from shot to dressing, min | 26.8 | 20.7 | 26.6 | 35.4 |
| Time from shot to bacterial sampling, min | 104 | 82.7 | 100 | 144 |
| Time from dressing to bacterial sampling, min | 77.6 | 56.8 | 73.8 | 110 |
| Warm carcass weight, kg | 315 | 228 | 290 | 505 |
| Dressing percentage, % | 52 | 48 | 52 | 56 |
| Bleeding success b, % | 3.1 | 2.2 | 3.1 | 4.0 |
| Temperature in slaughter premises, °C | 14 | 7 | 14 | 19 |
| Total bacterial count c, logCFU/cm2 | 1.4 | 0 | 1.6 | 2.6 |
a For temperature in slaughter premises, n = 18. b Estimated drawn blood weight divided by estimated live weight. c Total count of aerobic bacteria on carcass surface; no detected bacteria scored as 1 CFU/cm2 (CFU = colony-forming units).
Key statistics for individual animals at gunshot of cattle in Sweden, 2020.
| Animal no. | Shooting Order a | Age, Months | Live Weight, kg | Time to Shot b, min | Shooting Distance, m | Ammunition c | Reshooting | Shot Deviation d, mm | Skull Thickness e, mm | Brain Haemorrhage f | Stun Quality g | Stun-to-Stick Time, s | Blood Lactate, mmol/L | Total Bacterial Count h, logCFU/cm2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 1 | 19 | 480 | - | 8 | Soft | No | 20 | 10 | Moderate | Deep | 121 | 2.4 | 2.56 |
| 2 | 1 | 42 | 646 | - | 8 | Soft | No | 7 | 3 | Severe | Ambiguous | 123 | 3.1 | 1.60 |
| 3 | 1 | 54 | 900 | 76.8 | 10 | Hollow | No | 10 | 3 | Moderate | Deep | 115 | 1.8 | 2.00 |
| 4 | 2 | 42 | 770 | 90.6 | 11 | Hollow | No | 0 | 4 | Moderate | Deep | 117 | 1.7 | 1.40 |
| 5 | 1 | 19 | 460 | 61.1 | 9 | Hollow | No | 15 | 3 | Moderate | Poor | 85 | 3.4 | 2.18 |
| 6 | 2 | 19 | 470 | 55.3 | 9 | Hollow | No | 47 | 3 | Severe | Ambiguous | 96 | 2.1 | 1.60 |
| 7 | 1 | 19 | 560 | 66.8 | 9 | Hollow | No | 40 | 3 | Severe | Deep | 103 | 0.6 | 1.74 |
| 8 | 2 | 30 | 655 | 22.5 | 7 | Hollow | Yes | 58 | 36 | Moderate i | Poor j | 162 | 2.5 | 2.31 |
| 9 | 1 | 32 | 580 | 32.6 | 7 | Hollow | No | 10 | 3 | Severe | Ambiguous | 121 | 0.9 | 1.48 |
| 10 | 2 | 30 | 630 | 30.4 | 8 | Hollow | No | 9 | 3 | Severe | Ambiguous | 86 | 1.0 | 1.88 |
| 11 | 1 | 19 | 540 | 60.7 | 6 | Hollow | No | 15 | 8 | Severe | Deep | 88 | 1.9 | 1.30 |
| 12 | 2 | 32 | 680 | 49.7 | 9 | Hollow | No | 35 | 4 | Moderate | Ambiguous | 101 | 2.7 | 1.88 |
| 13 | 1 | 20 | 530 | 55.1 | 7 | Hollow | No | 25 | 3 | Moderate | Deep | 89 | 2.1 | 0.70 |
| 14 | 2 | 31 | 643 | 65.4 | 7 | Hollow | Yes | 21 | 7 | Severe i | Ambiguous j | 120 | 1.7 | 1.60 |
| 15 | 1 | 20 | 480 | 44.1 | 10 | Soft | No | 38 | 17 | Severe | Deep | 89 | 2.5 | 0 |
| 16 | 2 | 18 | 486 | 61.4 | 9 | Soft | No | 30 | 10 | Severe | Deep | 98 | 2.5 | 0 |
| 17 | 1 | 21 | 490 | 77.9 | 9 | Soft | No | 7 | 27 | Severe | Deep | 57 | 1.3 | 1.40 |
| 18 | 2 | 32 | 690 | 47.2 | 12 | Soft | No | 9 | 32 | Severe | Deep | 102 | 2.3 | 1.54 |
| 19 | 1 | 45 | 790 | 43.2 | 9 | Soft | No | 33 | 4 | Severe | Deep | 89 | 1.5 | 0 |
| 20 | 2 | 21 | 530 | 58.8 | 7 | Soft | No | 36 | 15 | Severe | Ambiguous | 49 | 1.8 | 0.70 |
a Shooting order on the same day. b Time from entry into stun corral to shot. c Soft = jacketed soft-point; hollow = semi-jacketed hollow-point. d Shot deviation from the intended target, which was located 2 cm caudally to the cross-section of two straight lines from the horn base to the contralateral outer eye angle; in reshot animals, measurements of the first shot. e Measured in the bullet entry hole; in reshot animals, measurements of the first shot. f Haemorrhage around the brainstem, classified as slight, moderate or severe. g Classified as ‘deep’, ‘ambiguous’ or ‘poor’ based on vital behavioural, eye-related and respiratory signs. h Total count of aerobic bacteria on carcass surface; no detected bacteria scored as 1 CFU/cm2 (CFU = colony-forming units). i Haemorrhage resulting from both shots. j Stun quality resulting from first shot.
Figure 6Schematic frontal view of the animal’s forehead at gunshot of cattle in Sweden, 2020, with hit locations relative to the intended target (origin) 2 cm caudally to the cross-section (x) of two straight lines from the horn base to the contralateral outer eye angle; using jacketed soft-point (grey) or semi-jacketed hollow-point (black) ammunition; circles represent reshot animals; marker labels are animal numbers.