Oxytocin induced oxidative stress in lactating Bubalis bubalis (Nili Ravi)

BACKGROUND Oxytocin has been reported for a wide range of adverse effects in different species of lactating animals. The present study was aimed to evaluate the adverse effects of oxytocin on biomarkers of oxidative stress in buffaloes. Lactating buffaloes (n = 40) were randomly selected from a commercial dairy farm located in the peri-urban area of district Faisalabad, Pakistan and divided into two equal groups viz. treatment and control groups, each containing 20 buffaloes. Buffaloes in treatment group were injected with oxytocin before each milking (morning and evening) for milk let down; whereas, animals in control group were milked naturally without oxytocin injection. Both the groups were assessed for oxidative stress biomarkers. RESULTS Results showed significantly higher levels (P ≤ 0.05) of TOS, tHcy and ceruloplasmin oxidase activity in lactating buffaloes injected with oxytocin as compared to those of control group. On the other hand, serum levels of TAS, PON1 and arylesterase were significantly lower (P ≤ 0.05) in the buffaloes of treatment group. CONCLUSIONS Oxytocin injection in lactating buffaloes resulted in elevated oxidative stress by increasing the total homocysteine and ceruloplasmin oxidase activity and decreasing enzymatic activities of antioxidant enzymes including paraoxonase-1 and arylesterase; that might render the animals to poor productive and reproductive potential.