Interrelationships between somatic cell count, lactation stage, lactation number, antioxidant enzymes and lipid peroxidation in dromedary (Camelus dromedaries) and bovine milk

In the present study, the relationship between milk SCC, differential leukocytes, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSHPx) activities and malondialdehyde (MDA) level, as well as the influence of lactation stage and lactation number in dromedary and cow milk were compared. A high positive correlation of SOD activity (P<0.01) with SCC and PMN in camel milk was observed. However, CAT and GSHPx activities increased with PMN in cow milk. It has been suggested that SOD may be useful to protect the mammary tissue during camel mastitis. A high correlation between MDA content, SCC and PMN for both species indicated the possibility of using MDA values to determine quality of cow and camel milk. Activities of CAT, GSHPx and SOD were found significantly lowered in late lactation. The data indicated that lipid peroxidation was significantly (P< 0.05) higher during early lactation for both species. There is no significant effect of lactation number (age) of the cows on the oxidative stress markers, however a significant increase of GSHPx activity with lactation number in camel milk was noted, this is reflected a potential antioxidant status in multiparous camels. Overall, it is concluded that the oxidative stress in cow and camel was high in early lactation.