Teaching Workshop: Bovine Spongiform Encephalopathy (BSE)
Air-Injection Stunning

Air-injection Stunning Prohibited

• January 12, 2004
  • FSIS published an interim final rule with request for comments. (69 FR 1885, January 12, 2004)
  • Amends FSIS regulations to prohibit air-injection stunning of cattle.

Air-injection Stunning

• Captive bolt stunners that deliberately inject compressed air into the cranium at the end of the penetration cycle shall not be used to stun cattle." (313.15 (b) (2) (ii))

Harvard Study

• Harvard Center for Risk Analysis conducted a risk assessment for BSE:
  • FSIS commissioned the study and released the results on November 30, 2001.
  • Among other things, the risk assessment compared standard captive bolt stunning and captive bolt stunning with air-injection.
  • Found that air-injection stunners can fail on occasion and result in an increase of CNS tissue disseminated into the circulatory system of cattle, thereby increasing the probability of BSE agent transfer.

Air-injection Stunning and BSE

• Other studies have shown that:
  • Air-injection stunning can force visible pieces of brain and other Central Nervous System (CNS) tissue-known as macro-emboli-into the circulatory system and organs of stunned cattle.
  • Most of the infectivity in cattle that have BSE is found in the CNS tissue (brain and spinal cord).

European Commission Opinion

• In early 2002, the European Commission's Scientific Steering Committee concluded that air-injection stunning was the method which had the highest risk of disseminating CNS tissues to other tissues and organs.

Air-Injection Stunning

• Changes in regulations:
  • Previous regulation 9 CFR 310.13 specifically listed air-injection captive bolt stunning as an approved method.
    • Amended to prohibit its use in cattle.
  • Regulation 313.15 (b) (2) (ii)
    • New paragraph added to prohibit air-injection stunners.

Stunning Devices Used in the U.S.

• Two types of captive bolt stunners:
  • Penetrative
  • Non-penetrative
• Most cattle slaughter plants in U.S. use penetrative captive bolt stun guns (without air-injection).
• FSIS does know that very few, if any, plants in the U.S. use air-injection stunning.

Stunning Methods

• FSIS inspection personnel verify that slaughter plants are using approved stunning devices.

Imported Beef

• Imported products must meet all safety standards for products produced in the U.S.
  • Therefore, foreign establishments that use air-injection stunning for cattle are prohibited from importing beef products into the U.S.

The Future

• There are relatively few studies on stunning techniques and CNS tissue.
• If further studies indicate that other stunning techniques introduce CNS tissues into the circulatory system of cattle, FSIS will consider prohibiting their use as well.