The effects of alternative electrical and mechanical stunning methods on hemorrhaging and meat quality of broiler breast and thigh muscles.

Five trials were conducted to determine the effects of various alternative stunning and restraining methods on the quality of chicken broiler meat. The stunning methods used were electrical whole-body and head-only stunning with different voltages (25 vs 100 V) and frequencies (50 vs 200 Hz), and mechanical captive bolt stunning. Before being stunned, the broilers were restrained either by shackling them by the feet, restraining their heads while they were standing, or placing them in a cone. Convulsions during and after stunning were subjectively scored. At 1 d post-mortem, the pH, color, and the intensity and number of hemorrhages, of breast and thigh muscles were measured. Convulsions were, in order of increasing intensity, observed after whole-body stunning using 50 Hz, whole-body stunning using 200 Hz, head-only stunning, and captive bolt stunning. No differences in ultimate pH were measured. A consistent difference in color was observed between whole-body and head-only stunning. Head-only stunning resulted in darker and more red (P < or = 0.01) breast muscles. Head-only and captive bolt stunning resulted in hemorrhages that were located more distal in the breast muscle than those observed after whole-body stunning. Captive bolt stunning (in a cone) resulted in fewer (P < or = 0.01) hemorrhages in breast and thigh muscles than whole-body stunning (100 V, 50 Hz, shackled), and in a similar level of hemorrhaging as electrical head-only stunning (25 V, 200 Hz, in a cone).

[1]  A. Raj.  An investigation into the batch killing of turkeys in their transport containers using mixtures of gases. , 1994, Research in veterinary science.

[2]  L. Wilkins,et al.  Broken bones in domestic fowls: effect of husbandry system and stunning method in end-of-lay hens. , 1990 .

[3]  E. Lambooij.  Electrical stunning by direct brain stimulation in pigs. , 1994, Meat science.

[4]  G. Eikelenboom,et al.  Concussion stunning of veal calves , 1981 .

[5]  L. Wilkins,et al.  Survival rate and carcase downgrading after the stunning of broilers with carbon dioxide-argon mixtures , 1992, Veterinary Record.

[6]  D. Blackmore,et al.  The effect of different slaughter methods on the post mortem glycolysis of muscle in lambs. , 1982, New Zealand veterinary journal.

[7]  Neville G. Gregory,et al.  Stunning of broilers , 1992 .

[8]  J. Veerkamp,et al.  Hemorrhages in muscles of broiler chickens: the relationships among blood variables at various rearing temperature regimens. , 1996, Poultry science.

[9]  S. Wotton,et al.  Effect of stunning on spontaneous physical activity and evoked activity in the brain. , 1990, British poultry science.

[10]  Sacit F. Bilgili,et al.  Electrical Stunning of Broilers - Basic Concepts and Carcass Quality Implications: A Review , 1992 .

[11]  N. Gregory,et al.  An evaluation of the effectiveness of handheld stunners for stunning chickens , 1990, Veterinary Record.

[12]  D. Carr,et al.  The effect of different methods of electrical stunning of lambs on blood pressure and muscular activity. , 1986, Meat science.

[13]  M. Hunt,et al.  Effects of Stunning Method and Time Interval from Stunning to Exsanguination on Blood Splashing in Pork1 , 1983 .

[14]  N. Gregory,et al.  Effect of electrical and gaseous stunning on the carcase and meat quality of broilers , 1990 .

[15]  L. Wilkins,et al.  Effect of slaughter method on bleeding efficiency in chickens , 1989 .

[16]  S. Lowry,et al.  EFFECTS OF SEX, AGE, PRESLAUGHTER FACTORS AND HOLDING CONDITIONS ON THE QUALITY CHARACTERISTICS AND CHEMICAL COMPOSITION OF TURKEY BREAST MUSCLES , 1982 .