Periparturient changes in oxidative stress and metabolic parameters in higher-parity Saanen goats with and without...

The periparturient period is a critical phase in dairy goats, during which metabolic and oxidative adaptations may influence maternal physiology and offspring viability. This study evaluated longitudinal changes in oxidative stress biomarkers, liver enzyme activities, and metabolic parameters in higher-parity Saanen goats with and without kid mortality at birth. Pregnant goats were followed prospectively and sampled longitudinally from three weeks before kidding to four weeks postpartum. After parturition, goats were grouped according to kid survival status at birth. Kid mortality at birth was defined as the presence of at least one kid that was stillborn or died during parturition before standing and suckling. Goats with kid mortality at birth were assigned to Group 1 (n = 6), while matched goats without kid mortality at birth were assigned to Group 2 (n = 6). Blood samples were collected at - 21, -14, and - 7 days prepartum, at kidding, and at 24 h, 48 h, 14 days, and 28 days postpartum. Serum total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), superoxide dismutase (SOD), paraoxonase-1 (PON-1), malondialdehyde (MDA), catalase (CAT), liver enzymes, and metabolic indicators were analyzed using repeated-measures mixed models. Goats with kid mortality at birth had higher TOS, OSI and SOD concentrations than controls (P < 0.05), suggesting increased oxidative burden and antioxidant response. Selected metabolic alterations, including changes in total protein and glucose concentrations, were also observed. Several parameters showed significant time effects and group × time interactions. These findings suggest that kid mortality at birth is associated with systemic oxidative imbalance and selected metabolic changes; however, results should be interpreted as preliminary associations rather than evidence of causality or predictive utility.