Abstract
Fermentation quality of mixed silage comprising roughages (corn silage, Italian ryegrass silage, rice whole crop silage and rice straw) and sweet-potato shochu distillery by-product cake (SDC) was determined. Three kinds of the mixed silage, 1) the above roughage only, 2) 10% SDC replaced roughage and 3) 20% SDC replaced roughage in a DM basis were prepared. Effects of feeding TMR containing mixed silage with SDC, i.e. 0% SDC (NSDCT), 10% SDC (10SDCT) and 20% SDC (20SDCT), on nutrient intake, rumen fermen-tation and nitrogen metabolism of 4 dry cows were elucidated according to 4×3 Youden square design (experiment 1). Effect on milk production of 6 lactating cows was also investigated according to 3×3 Latin square design (experiment 2). The fermentation qualities of the mixed silages with SDC was more than 70 points in V-SCORE, indicating good quality. There were no significant difference in apparent digestibility, TDN intake, rumen fermentation and nitrogen utilization among the treatments when the TMR containing mixed silage with NSDCT, 10SDCT and 20SDCT were fed to dry cows. When the above TMR were fed to lactating cows, dry matter intake was significantly higher in lactating cows fed the 10SDCT (25.2kg/day) or 20SDCT (24.9kg/day) than in those fed the NSDCT (22.1kg/day) (P < 0.05) ; however, milk yield and composition were not different among dietary treatments. It is concluded that ensiling self-supplying roughage with SDC shows good fermentation quality and TMR containing the silage is a beneficial variance as feed for dairy cows.
