Rodrigues et al., 2008. Livest. Res. Rural Dev. 20 (1) Article #6

Given the high amounts of apple rejected for commercialization its use as alternative feed for ruminants should be considered. This study was designed to investigate the nutritive value of apple pulp-wheat straw mixtures. Chemical composition, in vitro organic matter digestibility (IVOMD) and gas production profiles of ensiled mixtures containing 85 (M85), 70 (M70), and 50% (M50) of apple pulp were studied at 0, 15, 30 and 45 days. Fermentation quality was assessed by pH, lactic acid, ethanol and acetate. The results showed that non fibre carbohydrates (NFC) decreased along the storage period while DM stabilized after 30 days. It was also shown that pH increased along the storage period and the highest values for ethanol and acetic acid concentrations were observed in the apple pulp mixtures (Apple). Within mixtures, IVOMD decreased along the storage period, being however similar across mixtures after long periods of storage. Gas production analysis indicated that easily fermentable components (VFA) and the less easily fermentable constituents (VFB) decreased along the storage period, but VFB showed no differences between mixtures for the first two storage periods. Results suggest the possibility of reducing ethanol concentration of apple pulp silages through the incorporation of fibrous components; however silage additives to limit fermentation of sugars into ethanol should be used to ensure the course of the conservation process