We evaluated the effect of feeding early-harvested first-cut orchardgrass silage (OGS) instead of imported alfalfa hay (ALH) on dry matter intake (DMI), lactation performance, ruminal fermentation, digestion, and N utilization in dairy cows. Six multiparous Holstein cows were used in a replicated 3×3 Latin square design with three dietary treatments, involved gradually replacing ALH and flaked corn with 2 incremental levels of OGS (0, 50, 100%). We observed that dry matter and fiber digestibility, DMI and fat-corrected milk yield increased with an increasing OGS level in the diet. The rumen total volatile fatty acid concentration was not affected by dietary treatment. The ruminal ammonia-N concentration and the proportion of acetate and butyrate increased, and propionate decreased linearly with the increasing levels of OGS. As a proportion of N intake, the urinary N excretion decreased and the retention of N increased with increasing levels of OGS, with no dietary effect observed on N secretion in milk and fecal N excretion. These results show that OGS can be used as a substitute for ALH and flaked corn and that replacing ALH with OGS can be a good approach to improve milk production and N utilization and reduce concentrate input.

The aim of the present study was to evaluate the dry matter yield (DMY), chemical composition, and ruminal degradability of extremely late maturing guineagrass cultivar ‘Umaku’ with different growing periods in a warm temperate zone, compared with rhodesgrass. The ‘Umaku’ and rhodesgrass cultivar ‘Katambora’ were sown in late July in a farm field (Koshi, Kumamoto, Japan), and were harvested at 60, 75, and 90 days after seeding. The DMY of ‘Umaku’ increased concomitantly with longer growing periods and was always higher than that of ‘Katambora’. Longer growing periods correlated with lower crude protein and higher non-fibrous carbohydrate contents, but the neutral detergent fiber contents of the two grass species did not change. Ruminal degradability at the same growing period was identical in the two grasses, and decreased with longer growing periods. The DMY and ruminal degradability of ‘Umaku’ at 60 days were superior to those of ‘Katambora’ at 90 days. These findings indicate that the guineagrass cultivar ‘Umaku’ cultivated in a temperate zone has high potential as a nutritious feedstuff for cattle.

This study was aimed to elucidate relationships between soil freezing and overwintered growth of galega (Galega orientalis Lam.) in the Nemuro-Kushiro (Konsen) region, Hokkaido, by treatments in which soil freezing was artificially accelerated by uncovered snow, compared with the snow-covered control under single-row seeding (Exp. 1) and broadcast seeding mixed with timothy (Phleum pretense L., Exp. 2). No difference in overwintered growth was observed in 2016 (Exp. 1) due to extremely low yield, when the maximum soil freezing depth increased to more than 30 cm for both treated and control plots. In 2017, when there was a difference of about 10 cm in the soil freezing depth between treated and control plots, growth stagnation of galega was observed from overwintering to the first cut in the freezing treatments in both Exps. For these reasons, it is highly possible that freezing damage is a factor that inhibits the growth of overwintered galega.