Both spontaneous vaginal delivery and elective caesarean section influence neonatal redox status in dogs

BACKGROUND: The influence of birth mode on redox balance is unknown in dogs. We aimed to compare antioxidant activity and oxidative stress of puppies born by elective c-section or vaginal delivery. METHODS: Twenty-one bitches were elected for spontaneous vaginal delivery (n = 10) and elective cesarean section (n = 11) groups, considering only the first and last puppies born. Neonatal oxygen saturation, lactatemia, superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and total antioxidant capacity; marker of oxidative stress (thiobarbituric acid reactive substances [TBARS]) and protein oxidation were analysed at birth, 1 h, 12 h, 24 h and 72 h. RESULTS: C-section newborns had lower oximetry at birth and 1 h. Lactatemia was higher in the last vaginal delivery puppies and higher at birth, and 1 h. Regardless of birth mode, last puppies had hyperlactatemia at birth. Vaginal delivery puppies had higher TBARS, while protein oxidation was higher in c-section, mostly in last puppies. C-section puppies had higher GPx activity, whereas GSH concentration decreased overtime. Surgically born puppies had lowering SOD between 12 h and 72 h. CONCLUSIONS: Vaginal delivery enhances lipid peroxidation, counteracted mostly by GPx. Conversely, c-section triggers protein oxidation, acutely scavenged by SOD and GSH, thus puppies are less exposed to the negative consequences of oxidative stress.