Effect of lairage duration on some blood constituents and beef quality in bulls after long journey

With the aim to contribute to the determination of an adequate resting time for cattle after long transportation, the effects of different lairage times on some haematic parameters and meat quality of bulls subjected to long commercial journeys were investigated. Thirty-nine Limousine bulls supplied by one farm located near to Saragoza (Spain) were examined after 5 consignments at the final destination, following a journey of 2,550 km to the “San Giorgio” abattoir (Palermo, Italy). Transport time was of 53.6±10.9h; lairage duration for bulls of the 1st, 3rd and 5th consignments was of 31h on average (“Short Lairage” group), whereas, for those of the 2nd and 4th consignments, was of 59 and 57h, respectively (“Long Lairage” group). As regards the blood cell counts, data showed a significant effect (P<0.001) of the lairage duration on leukocyte and platelet counts. No significant effect was observed for erythrocyte count, haemoglobin and hematocrit in relation to the lairage duration, although the repeated measure analysis of variance showed that, irrespective of lairage duration, the hematocrit increased significantly between unloading and slaughter. Haematological parameters showed a significant (P<0.05) effect of the lairage time only on CK and Cortisol. CK enzyme showed an increase in the “Short Lairage” group (33.2% vs. 14.3%) whereas, Cortisol showed a decrease in the “Long Lairage” group (36.3% vs. 3.8%). The different lairage duration did not significantly (P>0.05) affect the incidence of slight and severe carcass bruises. As regards meat quality, lairage duration significantly influenced the pHu which was higher (P<0.01) in the muscle of the “Long Lairage” group, the luminosity at 24h post mortem which was significantly higher (P<0.05) in animals of the “Short Lairage” group, and the red and yellow indices which were higher in the “Long Lairage” group. The “Short Lairage” group showed a lower (P<0.01) value of cooking loss and higher (P<0.01) value of tenderness. Data show that pre-slaughter lairage duration after a long transport may influence the blood parameters as well as meat quality. On the whole, the increase in lairage duration over 36h does not determine any benefit for the animal’s well-being whereas it can cause a reduction in beef quality. For very long transports, it would be better to have an adequate organisation of the facilities in order to diminish the pre-slaughter lairage duration.