Changes in Water Soluble Carbohydrates Content of Timothy (<i>Phleum pretense</i> L.) in Pastures of TMR Centers over 4 Years

Abstract

Timothy ( <i> Phleum pretense </i> L.) pastures of 3 Total mixed ration (TMR) centers in Hokkaido were selected, the first cutting grasses were continuously collected from the same pastures on different harvest days over 4 years (2011-2014), and changes in the water soluble carbohydrates (WSC) content were analyzed to investigate the relationship with weather conditions. The harvest days in the 4-year period were June 17-22, June 24-26, June 27-30, and July 2-5, and grasses on these dates were designated as the harvest date groups. The weather data during the cutting period in each year were utilized. The WSC content tended to change yearly and it was significantly lower in the 4 groups (67.3 - 82.1 g/kg DM) in 2011 than in the groups (101.5 - 130.3 g/kg DM) in 2013 excluding the June 24-26 group (P < 0.05, P < 0.01). The WSC content tended to increase as the harvest date progressed in 2011-2013 and it significantly increased even though the harvest date was delayed only in 2013 (P < 0.01). It was suggested that differences in the WSC content among the years were related to the weather condition and dry matter yield of the grass.