Evaluation of preslaughter stress responses during waiting time at lairage in dromedary camels (Camelus dromedarius)

Stress responses were evaluated during waiting time at lairage at the slaughterhouse by analysing some physiological, haematological, biochemical and hormonal parameters in the camel. Sixteen male animals belonging to the municipal slaughterhouse of Casablanca (west of Morocco) were divided into 2 groups according to their waiting periods before slaughter: short period (12hs≤time<16hs, Group I, n=8) and long period (16hs≤time≤20hs, Group II, n=8). In groups I and II, neutrophil/lymphocyte ratio, haemolysis and circulating levels of cortisol, triiodothyronine and thyroxine were measured before waiting (at the end of transport and after unloading) and these were significantly (P<0.05) lower than those observed after the 2 waiting periods. After waiting time, all these parameters and plasma levels of glucose remained significantly (P<0.05) lower in Group II than those analysed in Group I. In the same conditions, rectal temperature, heart rate, respiratory rate and circulating levels of calcium, phosphorus and magnesium, showed no significant variation either between the stages (before and after waiting), or between the 2 waiting periods. In the camel, the waiting period at the slaughterhouse could be an important preslaughter stress factor, capable of altering the animal's physiology and the post-mortem quality of its meat. After transport and unloading, a waiting period of 16h to 20h could be considered less stressful than that of 12h to 16h in the camel. The impact of waiting period on antioxidant status will be evaluated later.