Mobile abattoir versus conventional slaughterhouse—Impact on stress parameters and meat quality characteristics in Norwegian lambs

The aim of the present study was to investigate possible differences in certain stress parameters and meat quality characteristics between Norwegian lambs slaughtered at a mobile abattoir (at two different localities) versus lambs slaughtered at a conventional, stationary slaughterhouse. Lambs slaughtered at the conventional slaughterhouse had higher serum cortisol levels than lambs slaughtered at a mobile abattoir (P < 0.001). Also blood glucose values were significantly lower at one of the two mobile slaughter localities compared to the stationary abattoir (P < 0.001). Animals at the conventional slaughterhouse displayed a higher frequency of vocalizations (P < 0.01) and showed more aggressive behaviour than lambs at the mobile slaughterhouse (P < 0.01). It was demonstrated that meat from lambs slaughtered at the mobile slaughterhouse had lower ultimate pH (P < 0.001). Also, meat from one of the mobile slaughter locations was more tender (having a lower Warner Bratzler shear force value, WB), compared to meat from the lambs slaughtered at the conventional abattoir (P < 0.05). Furthermore, some relationships between stress indicators and meat quality were demonstrated. WB was positively correlated to serum cortisol level (r = 0.39, P < 0.05). There was a positive correlation between serum cortisol level and the incidence of aggressive interactions (r = 0.47, P < 0.05). The frequency of aggressive interactions was positively correlated to number of vocalizations (r = 0.73, P < 0.01) and also muscle pH (r = 0.66, P < 0.05). Finally, the frequency of aggressive behaviours was negatively correlated to blood glucose levels (r = 0.46, P < 0.05).