Effects of Grazing in a Sown Pasture with Forestland on the Health of Japanese Black Cows as Evaluated by Multiple Indicators.

The objective of the present study was to evaluate the effects of extensive grazingin a sown pasture with forestland on the health of beef cows by measuring multiple indicators. Ten Japanese Black beef cows were used in this experiment. Five of the ten cows were grazed for two months on a 1.8 ha field. The remaining cows were fed under confinement conditions. Behavioral assessments showed that grazing increased sternum lying with rumination of the cows. The grazing cows did not show any abnormal behaviors. There was a tendency for the numbers of red blood cells and lymphocytes to be lower in grazing cows than in confined cows, whereas the number of neutrophils in grazing cows was significantly higher than that in confined cows. In addition, grazing cows had a higher total antioxidant capacity and glutathione peroxidase activity than confined cows. These results suggest that extensive grazing in a sown pasture with forestland increases natural behaviors, decreases circulating red blood cells and lymphocytes and enhances neutrophil circulation, antioxidant enzyme activity, and antioxidant capacity.