Preslaughter handling of pigs and the effect on heart rate, meat quality, including tenderness, and sarcoplasmic reticulum Ca(2+) transport.

It is known that stress applied to pigs can be of influence on meat quality combined with disturbed regulation of the intracellular Ca(2+) concentration. However, the effect on meat tenderness is not sufficiently known. In an experiment with pigs two kinds of stress (immobilisation by a nose snare (nose) and the use of an electrical goad (goad)) for 5min just before slaughter were used and the results compared with minimum stress pigs (control). To quantify the level of stress, the heart rate during stress application was determined and it was found that the stress effect was highest in the goad pigs and surprisingly decreasing during the use of a nose snare. The meat quality did not differ between nose and control pigs, but was inferior in the goad group. Also, the goad stress significantly reduced the Ca(2+) transport of the sarcoplasmic reticulum. The principal hypothesis, that a disturbed Ca(2+) transport will affect the tenderness by activating the calpain system, could not be verified. Tenderness did not differ between experimental groups using 24 h post-mortem samples, neither was there a difference in tenderness after storing the meat samples for 6 days.