Determination of the activity of selected antioxidant enzymes during bovine laminitis, induced by oligofructose overload

Abstract

Alimentary oligofructose (OF) overload induces acute laminitis in dairy heifers. We examined the correlation between acute bovine laminitis and antioxidant levels by measuring the activities of malondialdehyde (MDA), catalase (CAT), reduced glutathione (GSH), and superoxide dismutase (SOD) in dairy heifers with acute bovine laminitis. A total of 12 clinically healthy non-pregnant Chinese Holstein heifers, aged between 18-26 months (20.67 ± 3.01 mo), weighing 335-403 kg (379.71 ± 19.87 kg), and with BCS ranging from 2.7 to 3.3 were selected and divided into two groups of six animals: an OF-treated group and a control group. The OF-treated heifers (n = 6) received 17 g/kg BW of oligofructose dissolved in 2 L/100 kg BW of tap water, whereas the control heifers (n = 6) received 2 L/100 kg BW of tap water. Blood samples of OF-treated and the control heifers were collected at –72 h before, as well as 0, 6, 12, 18, 24, 36, 48, 60 and 72 h after OF overload. Malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH), and catalase (CAT) activity levels were measured by authenticated standard methods using blood samples. The mean concentration of superoxide dismutase (SOD) was significantly lower (p < 0.01) in the OF-treated heifers from 24 h to 72 h and significantly lower (p < 0.05) at 18 h compared to the control group. Malondialdehyde (MDA) level was significantly higher (p < 0.01) at 24 h to 72 h and significant increased (p < 0.05) at 12 h to 18 h in OF-treated heifers compared with healthy heifers. There were no significant differences in GSH and CAT activities between the control and treatment groups. Our study showed that inadequate levels of antioxidants (enzymatic and non-enzymatic) may be linked to oxidative stress in sick heifers. OF-treated heifers had decreased SOD and increased MDA in response to acute laminitis. Therefore, SOD, GSH, CAT, and MDA activities may play a dynamic role in the etiopathogenesis of acute laminitis in dairy heifers. However, further detailed research is required to describe these responses and to develop strategies to control acute laminitis.