The nutritional value of pressed potato vine silage

Abstract

Potato (Solanum tuberoswn L.) vines were studied to determine if they could be successfully ensiled and fed to ruminant animals. Russet Burbank potato vine and alfalfa (Medicago sativa L.) silages were fed to goats (Capra hircus) to measure in vivo digestibility and to determine if potato glycoalkaloids were aversive or toxic. No differences in the feeding patterns between control and experimental animals were observed. Alfalfa silage was more digestible than the Russet Burbank potato vine silage due to a higher content of digestible cell wall materials. Digestibility differences between potato clones and harvest dates were found when in vivo digestibility tests were performed. W729R was the most digestible clone studied, especially for the early harvest dates. Most of the clones had vines that were more digestible, in vitro, than alfalfa. Vine glycoalkaloid contents of the experimental clones were similar to the values reported in the literature. There was no apparent correlation between vine glycoalkaloid content and percent digestible dry matter. A positive correlation of 0.38 between digestible dry matter and dry vine yield was found. Potato vine silage, produced after pressing the vines to remove water, was an acceptable feed for ruminant animals. Additional in vivo testing is necessary to determine if toxic effects due to glycoalkaloids or pesticides from long term feeding will be a problem.