Cultivation and ensilage of yacon plants (Smallanthus sonchifolius [Poepp. & Endl.] H. Robinson) and the function of yacon silage

Abstract

Yacon (Smallanthus sonchifolius [Poepp. & Endl.] H. Robinson) plant cultivation has extended rapidly throughout Japan since 1985 because of its utility as a tuberous root crop. In this study, strains with high yields of both above‐ground and underground parts were identified to investigate the use of above‐ground parts for animal feed silage. In addition, we measured the anti‐oxidative activity of the silage as a functional characteristic. Data from 5 years of the cultivation of 17 yacon strains suggest that the most suitable strain for planting in the Aso region of Japan is SY217, which has a high yield of both above‐ground parts and tuberous roots. The root tuber parts of yacon are used almost entirely as food; actually, most foliage parts are hardly used, except for some above‐ground parts, which are used as tea. The fermentation qualities of the silage using all above‐ground parts and harvest residue tuberous roots (harvest residues) are high and their dry matter digestibility, investigated using pigs, is 66.7%. Fresh above‐ground parts had very strong anti‐oxidative activity as compared with butylated hydroxyanisole and α‐tocopherol. In addition, that activity is retained during ensiling for 4 weeks. These results suggest that the entire yacon plant can be used effectively as a feedstuff resource with the added bonus of anti‐oxidant activity.

Effect of yacon silage on feed digestibility, blood characteristics and amount of urinary 8‐hydroxydeoxyguanosine in ewes

“…However, a large amount of the foliage parts of yacon are hardly used. Therefore, we suggest that the entire yacon plant is used as a feed resource by ensiling, as discussed in the previously published report (Koike et al 2009).…”

“…In conclusion, it is suggested that YS can be used not only as feed for monogastric animals (Koike et al. 2009), but also as a supplementary feed in ruminants.…”

“…Yacon strains were provided by the National Agricultural Research Center for Western Region. Yacon plants were cultivated as reported previously (Koike et al. 2009).…”

“…1995). In a previous study, we suggested that the entire YS could be useful as a feed resource for monogastric animals (Koike et al. 2009).…”

“…2009). Therefore, the objective of this experiment was to determine the effects of the YS made by the previously published method (Koike et al. 2009) on the blood characteristics and the body weight change of ewes, and the amount of ewes’ urinary 8‐OHdG when the oxidative stress is applied compared with bermudagrass ( Cynodon dactylon ) hay (BH) which is a common roughage in Kumamoto prefecture.…”