الكاتب: Multiple References

Pain inflicted by routine animal husbandry procedures, such as castration, is a major animal welfare concern in beef production (Oltjen & Mitloehner, 2003). Pain is defined as an aversive feeling or sensation associated with actual or potential tissue damage, resulting in physiological, neuroendocrine, and behavioral changes that indicate a ‘stress’ response (Broom, 2000; Anderson & Muir, 2005). Castration of cattle destined for slaughter in the USA is a common practice (Chase et al., 1995). Based on the number of steers weighing >227 kg (500 lbs) reported by the US Department of Agriculture National Agricultural Statistics Service (USDA NASS, 2006), there are approximately 14.9 million bovine castrations performed in the USA annually. The American Veterinary Medical Association (AVMA) considers castration to be one of the most stressful experiences for livestock. Research in developing improved techniques for painless, humane castration is considered a priority (AVMA, 2006).