4. Conclusion
The results of the current study indicate that both transportation
for 75 min and handling practices including catching at finishing
pen and driving to the lairage unit can cause a stress in lambs as indicated
by increased level of plasma cortisol, CK and glucose. However,
there were no significant changes in haematological stressparameters, such as PCV, HGB and RBC due to transportation. Overnight
lairage without food intake (in TS-L18 h treatment) produced
an increase in PCV, HGB and RBC, which may be the indication of dehydration.
Pre-slaughter treatment, in which transported lambs were
slaughtered after 30 min resting period, yielded higher plasma glucose
level at exsanguination, which may cause a higher ultimate
meat pH compared with those of other treatments.
Lambs transported for 75 min and then slaughtered after 30 min
resting time (TS-L30 min treatment) had less tender meat (having a
higher Warner Bratzler shear force value), lower meat lightness
value (L*) at 0 h and 1 h after cutting and lower meat water holding
capacity than those of other pre-slaughter treatments, which could
be associated with a higher meat pH at 24 h post mortem in lambs
of TS-L30 min treatment.
As a consequence, results of the current study for meat tenderness,
lightness value and water holding capacity indicate that slaughter
of lambs after 30 min lairage may result in a lower meat quality
compared with slaughter of lambs after overnight lairage or without
transport. Therefore, from the meat quality point of view, slaughter
of lambs after 30 min resting duration is not recommended to the
farmers or abattoirs.