2019 Volume 72 Issue 3 Pages 147-153
The objective of this study was to investigate the effect of dietary supplementation with trehalose on oxidative-stress markers in the blood, milk and rumen fluid of dairy cows during the hot or comfortable season. The respective average maximum daytime temperatures in the hot and comfortable seasons were 34.2°C and 18.5°C. Six Holstein dairy cows housed in a freestall barn were divided into two groups, with each group receiving a different dietary treatment (control diet or 1.5% trehalose-supplemented diet) following a 2×2 crossover study in both seasons. In the hot season, food intake increased in trehalose-supplemented cows (P＜0.01); while milk yield and milk components were unchanged by trehalose supplementation in both seasons. In terms of the number of protozoa, the number of Entodinium increased with trehalose supplementation in both seasons (P＜0.05). The values of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in milk increased with trehalose supplementation in both seasons (P＜0.05). Furthermore, the values of DPPH radical scavenging activity in plasma tended to increase with trehalose supplementation in the hot season. Dietary supplementation with trehalose resulted in the improvement of antioxidant activity in milk and blood. These findings suggest that trehalose supplementation might be effective for reducing oxidative stress in dairy cows during the hot season.
