Topics:
Animal Refresher, Meat Science
CO2 Concentration and Time for Chemical Stunning
The concentration of CO₂ and exposure time in case of chemical stunning should be:
- 70% CO₂ for 45 seconds — Correct Answer
- 80% CO₂ for 60 seconds
- 65% CO₂ for 60 seconds
- 50% CO₂ for 30 seconds
Explanation:
Correct Answer: 70% CO₂ for 45 seconds
In chemical (gas) stunning, a mixture of 70% CO₂ and 30% O₂ is used for 45 seconds. This is most suitable for pigs.
How CO₂ Stunning Works
- CO₂ blocks the nerve endings in the brain, rendering the animal unconscious without pain.
- The main function of CO₂ in gas stunning is blocking the nerve endings.
- It does NOT cause hemorrhage or blackening of subcutaneous tissue.
Comparison of Stunning Methods
- Mechanical stunning (captive bolt pistol, percussion stunner): most commonly used in cattle & buffaloes.
- Electrical stunning (Elther apparatus): alternating current of 250 mA & 75 volts for 10 seconds; used in sheep, goat, pigs & poultry.
- Chemical/Gas stunning (CO₂): most suitable for pigs; 70% CO₂ for 45 seconds.
Why Other Options Are Wrong
- 80% CO₂ for 60 sec — too high concentration and too long; not the recommended protocol.
- 65% CO₂ for 60 sec — incorrect concentration and time.
- 50% CO₂ for 30 sec — insufficient concentration and duration for effective stunning.
📚 About this Topic — Animal Refresher
This multiple choice question is from Animal Refresher, Meat Science. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Refresher to strengthen your preparation.
