Evaluation of milk glutathione peroxidase and superoxide dismutase levels in subclinical mastitis in Damascus goats

Abstract

The aim of this study was to evaluate milk glutathione peroxidase (GPx) and superoxide dismutase (SOD) levels in Damascus goats with subclinical mastitis. According to the somatic cell counts (SCCs), 193 Damascus goats included in the study were divided into healthy (n = 75; SCC <1000 × 103 cell/mL) and mastitis (n = 118; SCC ≥1000 × 103 cell/mL) groups. It was determined that GPx levels were 271.76 ± 3.16 U/L and 300.47 ± 9.04 U/L and SOD levels were 2.57 ± 0.09 U/mL and 2.23 ± 0.07 U/mL in the healthy and mastitis group, respectively. Our findings show that the GPx (P < 0.001) and SOD (P < 0.05) levels were different between the groups. Weak correlations were also found between somatic cell counts and GPx levels (Spearman's R = 0.296, P < 0.001) and SOD levels (Spearman's R = -0.163, P = 0.024). The model showed that GPX (P = 0.003) and SOD (P = 0.004) levels were different according to the SCCs in healthy and mastitic milk samples, respectively. However, individual differences like age, parity, and number of offspring had no effect on milk GPx and SOD levels (P > 0.05). In summary, a significant increase in GPx and decrease in SOD levels, respectively, were determined in goat milk samples with subclinical mastitis, and these changing trends were correlated with milk SCCs. However, age, parity, and number of offspring were not associated with these changing patterns.