Contents of macro- and microelements in blood serum and breast muscle of broiler chickens subjected to different variants of pre-slaughter handling

During pre-slaughter handling, poultry is exposed to a variety of co-acting stimuli: sudden displacement, vehicle movement, speeding up, vibrations, jolts, noise, lack of feed and water, restriction of natural behaviours, disturbance of flock hierarchy, restriction of living space, exposure to pain, and change of transport microclimate (Duncan, 1989; Broom, 1990; Mitchell and Kettlewell, 1998). The accumulation of such a great number of stress factors in such a short period of time results in diminished immunity of birds as well as in physiological and morphological changes in their bodies. Those effects are primarily manifested by changes in the blood composition, changes in the structure of muscle tissue, body weight losses and increasing death rate as well as by damage to bird carcasses and deterioration of their meat quality (Kettlewell, 1989; Weeks and Nicol, 2000; Warriss et al., 2005; Večerek et al., 2006; Wojcik, 2007). A high number of stress stimuli acting in the preslaughter handling disturb an organism’s homeostasis. This, in turn, leads to a loss of macroand microelements, deficiency of which in meat may affect its quality (Mowat, 1994; Podgorski et al., 2001; Truchlinski et al., 2007). Available literature provides no data on any trial of monitoring changes in contents of macroand microelements simultaneously in blood and meat of poultry subjected to the action of various stress-bearing factors. Hence, the study was undertaken to determine the contents of Ca, Mg, Na, K, P, and Fe in blood serum and breast muscles of broiler chickens subjected