Nijboer J, Van Vuuren A, Ensing E. 2007. Effect of additives on ensiling of willow leaves and twigs. In Ward A, Hunt A, Maslanka M, Eds. Proceedings of the Seventh Conference on Zoo and Wildlife Nutrition, AZA Nutrition Advisory Group, Knoxville, TN.
According to Hoffman, ruminants can be classified as browsers (“concentrate selectors”), intermediate feeders, and grazers. Compared to grazers, browsers have different nutritional requirements to meet their specific digestive physiology needs. In general, browse may contain higher amounts of secondary plant compounds and lower fiber concentrations than many grasses. In Rotterdam Zoo, browse often consists of willow leaves and branches. However, for year-round availability of browse, it needs to be preserved for winter and spring feeding. Browse can be conserved in three ways: freezing at -20°C, natural or artificial drying, or ensiling. Ensiling (production of lactic acid from soluble sugars by anaerobic fermentation) is a new method of preservation of browse forages in temperate regions. It is unknown whether willow leaves and branches contain sufficient epiphytic lactic acid bacteria to obtain a rapid fermentation start. Another problem with willow branches is the low density that can be obtained, which hampers anaerobiosis. Therefore, the effect of different preservation methods on the fermentation quality of willow leaves and branches was studied in two experiments.Nijboer – EFFECT OF ADDITIVES ON ENSILING OF WILLOW LEAVES AND TWIGS.pdf     818 KB