The Effects of Lactic Acid Bacterial Inoculants on the Fermentation, Aerobic Stability and In Vitro Organic Matter Digestibility of Sunflower Silages

Abstract

This study was carried out to determine the effects of homofermentative and/or heterofermentative lactic acid bacteria inoculants on the fermentation, aerobic stability and in vitro organic matter digestibility characteristics of sunflower silages.  Sunflower was harvested at the milk stage of maturity. Inoculant 1188 (Pioneer®, USA) was used as homofermentative lactic acid bacteria whereas inoculant 11A44 (Pioneer®, USA) was used as heterofermentative lactic acid bacteria inoculant. Inoculants were applied to the silages at 6.00 log₁₀ cfu/g levels. After treatment, the chopped whole crop sunflower was ensiled in 1.0-litre special anaerobic jars, equipped with a lid enabling gas release only. The jars were stored at 25±2°C under the laboratory conditions. Three jars from each group were sampled for chemical and microbiological analyses 2, 4, 8 and 60 days after ensiling. At the end of the ensiling period, all silages were subjected to an aerobic stability test for 5 days. In addition, in vitro organic matter digestibilities of those silages were determined. The results revealed that homofermentative lactic acid bacteria inoculants increased the characteristics of fermentation but impaired the aerobic stability of the sunflower silages. However, the application of heterofermentative lactic acid bacteria increased the concentration of acetic acid and the aerobic stability of the sunflower silages.