Alternatives to Carbon Dioxide in Two Phases for the Improvement of Broiler Chickens’ Welfare during Stunning
Abstract
:Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Experimental Design and Facilities
2.2. Gas Concentration Assessment
2.3. Brain Activity Assessment
2.4. Behavioural Assessment
2.5. Data Pre-Processing and Statistical Analyses
3. Results
3.1. Gas Concentration Assessment
3.2. Brain Activity Assessment
3.3. Behavioural Assessment
3.3.1. Behavioural Assessment of Loss of Posture and Motionlessness
3.3.2. Behavioural Assessment before Loss of Posture
3.3.3. Behavioural Assessment after Loss of Posture
3.3.4. Relationships between EEG and Behaviour
4. Discussion
4.1. Gas Mixture Concentration and Stability Assessment
4.2. Brain Activity Assessment
4.3. Behavioural Assessment
4.3.1. Behavioural Assessment of Loss of Posture and Motionlessness
4.3.2. Behavioural Assessment before Loss of Posture
4.3.3. Behavioural Assessment after Loss of Posture
4.4. Relationship between Brain Activity and Behavioural Assessment
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Item | Day 1 | Day 2 | Day 3 | Day 4 | Day 5 | |||
---|---|---|---|---|---|---|---|---|
Session | 1500 to 1900 h | 800 to 1200 h | 1500 to 1900 h | 800 to 1200 h | 1500 to 1900 h | 800 to 1200 h | 1500 to 1900 h | 800 to 1200 h |
Treatment | AIR | 40C90C | 40C60N | 40C60N | 20C80N | 20C80N | 40C90C | 40C90C |
cycles, n | 25 | 10 | 10 | 11 | 9 | 9 | 8 | 8 |
Total birds, n | 100 | 30 | 35 | 44 | 36 | 36 | 32 | 30 |
Birds/cycle | 4 | 3 | 3–4 * | 4 | 4 | 4 | 4 | 3–4 ** |
Brain activity assessment, n | 0 | 0 | 5 | 11 | 9 | 9 | 8 | 8 |
Behavioural assessment, n | 100 | 30 | 30 | 33 | 27 | 27 | 24 | 22 |
Cycles, n | 25 | 10 | 10 | 11 | 9 | 9 | 8 | 8 |
Behaviour | Description | Adapted from |
---|---|---|
Loss of posture | Cessation of standing, with the head resting against either the floor or wall of the gas stunning system. | [10,26] |
Motionlessness | Limp carcass, with the bird being completely still including the cessation of visible breathing movements. | [27] |
Sitting | Legs underneath the body and wings relaxed against body. | [28] |
Standing | On their feet with the body fully or partly lifted off of the ground. | [24] |
Walking | Moving forward at a regular pace. | [29] |
Ataxia | Uncoordinated walking with exaggerated lateral movement or fluttering when standing to maintain posture. | [10] |
Deep inhalation | Wide open-mouth breathing with neck extension. | [10] |
Gasping | Opening and closing mouth without neck extension and with reduced frequency compared to physiological breathing. | [10] |
Head shaking | Rapid side-to-side movement of the head, which occurs whilst the bird is standing, walking, or sitting. | [10] |
Jumping | Any vertical movement from a plantar stance, resulting in both feet leaving contact with the floor. | [10] |
Leg paddling | Leg movements in the air or towards the ground depending on the body position of the bird. It can also be determined by an alternating upwards and downwards movement of the body if bird is lying sternal. | [28] |
Wing flapping | Bouts of fast, short flapping, rapid movement of the wings. | [10,30] |
High-pitch vocalisations | Single or repeated short and loud shrieking (screaming). | [4] |
Treatments | |||||
---|---|---|---|---|---|
Analysis | Outcome | 40C90C | 40C60N | 20C80N | p-Value |
Spectral | Loss of consciousness, s * | NA | 25.7 ± 7.0 | 20.7 ± 6.6 | 0.144 |
Spectral | Death, s ** | NA | 65.8 ± 14.1 b | 122 ± 53.2 a | 0.048 |
Visual | Death, s *** | NA | 69.8 ± 11.9 | 66.3 ± 8.1 | 0.456 |
Treatment | |||||
---|---|---|---|---|---|
Behaviour | 40C90C | 40C60N | 20C80N | SE | p-Value |
Loss of posture | 59.2 (26.0–156.5] a | 19.8 (14.0–30.8] b | 22.3 (15.8–37.0] b | 2.7 | <0.001 |
Motionless | 168.8 (89.0–212.7] a | 66.1 (43.0–108.0] b | 70.4 (45.2–88.5] b | 3.5 | <0.001 |
Treatment | ||||||
---|---|---|---|---|---|---|
Item | Behaviour | 40C90C | 40C60N | 20C80N | SE | p-Value |
Proportion, (%) | Head shaking | 76/76 (100%) | 63/63 (100%) | 54/54 (100%) | - | 1.000 |
Deep inhalation | 76/76 (100%) | 63/63 (100%) | 54/54 (100%) | - | 1.000 | |
HPV | 42/76 (55.3%) | 43/63 (68.3%) | 53/54 (98.1%) | - | 0.101 | |
Gasping | 20/76 (26.3%) | 0/63 (0.0%) | 0/54 (0.0%) | - | - | |
Sitting | 75/76 (98.7%) | 58/63 (92.1%) | 50/54 (92.6%) | - | 0.951 | |
Standing | 71/76 (93.4%) | 51/63 (81.0%) | 48/54 (88.9%) | - | 0.848 | |
Walking | 45/76 (59.2%) | 25/63 (39.7%) | 28/54 (51.9%) | - | 0.413 | |
Ataxia | 63/76 (82.9%) | 55/63 (87.3%) | 48/54 (88.8%) | - | 0.297 | |
Wing flapping | 20/76 (26.3%) c | 35/63 (55.5%) b | 43/54 (79.6%) a | - | 0.001 | |
Events/bird, n | Head shaking | 5.4 (1–12) | 4.8 (1–9) | 5.1 (1–9) | 0.3 | 0.069 |
Deep inhalation | 9.4 (2–18) a | 3.9 (1–9) b | 4.8 (0–9) b | 0.4 | <0.001 | |
HPV | 2.9 (0–12) a | 2.0 (0–6) b | 3.3 (0–11) a | 0.4 | 0.001 | |
Gasping | 0.7 (0–10) | 0 (0–0) | 0 (0–0) | 0.2 | - | |
Sitting | 2.1 (1–6) a | 1.3 (0–3) b | 1.6 (0–4) ab | 0.2 | <0.001 | |
Standing | 2.0 (0–7) a | 1.1 (0–3) b | 1.3 (0–4) b | 0.2 | 0.004 | |
Walking | 1.2 (0–7) a | 0.6 (0–3) b | 0.7 (0–3) b | 0.2 | <0.001 | |
Wing flapping | 0.4 (0–4) c | 0.6 (0–2) b | 1.0 (0–3) a | 0.1 | <0.001 | |
Total duration, s | Sitting | 35.9 (3.4–135.1) a | 7.4 (0–19.5) b | 6.9 (0–22.8) b | 2.7 | <0.001 |
Standing | 13.4 (0.0–37.9) a | 7.5 (0.0–22.2) b | 8.5 (0–18.2) b | 1.1 | <0.001 | |
Walking | 2.6 (0.0–11.8) a | 1.5 (0.0–10.5) b | 1.5 (0.0–9.3) b | 0.5 | 0.024 | |
Ataxia | 4.6 (0.0–19.7) a | 2.7 (0.0–7.1) b | 3.6 (0.0–8.2) ab | 0.5 | <0.001 | |
Wing flapping | 0.7 (0.0–6.8) c | 1.1 (0.0–6.2) b | 2.3 (0.0–6.5) a | 0.3 | 0.021 |
Treatment | ||||||
---|---|---|---|---|---|---|
Item | Behaviour | 40C90C | 40C60N | 20C80N | SE | p-Value |
Proportion, n (%) | Gasping | 43/76 (56.6%) a | 14/63 (22.2%) b | 14/54 (25.9%) b | - | 0.009 |
Jumping | 60/76 (7.9%) b | 7/63 (10.5%) b | 14/54 (25.0%) a | - | 0.003 | |
Leg paddling | 75/76 (98.7%) | 63/63 (100%) | 54/54 (100%) | - | 0.998 | |
Wing flapping | 53/76 (69.7%) | 61/63 (96.8%) | 53/54 (98.1%) | - | 0.320 | |
HPV | 65/76 (85.5%) | 53/63 (84.1%) | 53/54 (98.1%) | - | 0.818 | |
Events/bird, n | Gasping | 2.5 (0–16) a | 0.4 (1–3) b | 0.3 (0–3) b | 0.4 | <0.001 |
Jumping | 0.1 (0–2) b | 0.2 (0–3) ab | 0.4 (0–3) a | 0.1 | <0.001 | |
Leg paddling | 3.9 (0–10) b | 4.3 (2–8) ab | 4.6 (0–9) a | 0.3 | 0.041 | |
Wing flapping | 1.5 (0–0) c | 2.4 (0–7) b | 3.1 (0–7) a | 0.3 | <0.001 | |
HPV | 1.8 (0–10) | 1.5 (0–7) | 1.8 (0–4) | 0.3 | 0.297 | |
Total duration, s | Leg paddling | 14.3 (1.5–36.5) b | 18.2 (4.0–39.3) a | 19.0 (2.0–36.9) a | 1.3 | <0.001 |
Wing flapping | 0.7 (0–6.8) c | 1.1 (0–6.2) b | 2.3 (0–6.5) a | 0.3 | <0.001 |
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Rucinque, D.S.; Velarde, A.; Xercavins, A.; Varvaró-Porter, A.; Gibson, T.J.; Michel, V.; Contreras-Jodar, A. Alternatives to Carbon Dioxide in Two Phases for the Improvement of Broiler Chickens’ Welfare during Stunning. Animals 2024, 14, 486. https://doi.org/10.3390/ani14030486
Rucinque DS, Velarde A, Xercavins A, Varvaró-Porter A, Gibson TJ, Michel V, Contreras-Jodar A. Alternatives to Carbon Dioxide in Two Phases for the Improvement of Broiler Chickens’ Welfare during Stunning. Animals. 2024; 14(3):486. https://doi.org/10.3390/ani14030486
Chicago/Turabian StyleRucinque, Daniel Santiago, Antonio Velarde, Aida Xercavins, Aranzazu Varvaró-Porter, Troy John Gibson, Virginie Michel, and Alexandra Contreras-Jodar. 2024. "Alternatives to Carbon Dioxide in Two Phases for the Improvement of Broiler Chickens’ Welfare during Stunning" Animals 14, no. 3: 486. https://doi.org/10.3390/ani14030486