title: Assessment of Pediococcus acidilactici as a Potential Silage Inoculant.
abstract: Eighteen Pediococcus strains were screened for their potential as silage inoculants. Pediococcus acidilactici G24 was found to be the most suitable, exhibiting a short lag phase on both glucose and fructose, a rapid rate of acid production, a high sugar-to-lactate conversion efficiency, no detectable breakdown of proteins or lactic acid, and the ability to grow within a broad range of pH and temperature. When tested in laboratory silos using grass with a water-soluble carbohydrate content of 24 g/kg of aqueous extract, P. acidilactici G24 stimulated the natural Lactobacillus plantarum population and accelerated the rates of lactic acid production and pH decrease. After 6 days of fermentation, the inoculated silage exhibited a 12% decrease in ammonia nitrogen and an 11% increase in crude protein levels compared with uninoculated controls. The use of an L. plantarum inoculant at a rate of 10 bacteria per g of grass in conjunction with P. acidilactici G24 produced no additional beneficial effect. Inoculation of grass with a water-soluble carbohydrate level of 8 g/kg of aqueous extract with P. acidilactici G24 led to no acceleration in the rate of L. plantarum growth or pH decrease. However, after 7 days of fermentation the inoculated silage had a 14% lower ammonia nitrogen protein content than did uninoculated controls. The results suggest that P. acidilactici G24 may be useful as a silage inoculant for crops with a sufficiently high water-soluble carbohydrate level.
authors.affiliation: School of Biological Sciences, Dublin City University, Glasnevin, Dublin 9, and Teagasc, Grange Research Centre, Dunsany, County Meath, Ireland.
authors.forename: A
authors.initials: A
authors.lastname: Fitzsimons
authors.forename: F
authors.initials: F
authors.lastname: Duffner
authors.forename: D
authors.initials: D
authors.lastname: Curtin
authors.forename: G
authors.initials: G
authors.lastname: Brophy
authors.forename: P
authors.initials: P
authors.lastname: O'kiely
authors.forename: M
authors.initials: M
authors.lastname: O'connell