Effects of ensiling whole crop maize with bacterial inoculants on the fermentation, aerobic stability, and growth performance of lambs

The aim of this study was to determine effects of ensiling whole crop maize with the bacterial inoculants Bonsilage mais flussig (BMF) and Lalsil Fresh LB (LFLB) on fermentation, aerobic stability and growth of lambs. Whole crop maize (288 DM g/kg) was ensiled with no additive, BMF or LFLB for 60 days in 1.5 l jars and 3 months in 210 l drums. To follow the fermentation dynamics during ensiling, 1.5 l jars were opened on days 0, 4, 10, 21 and 60 of ensiling for sampling and analysed for pH, water-soluble carbohydrates (WSCs), volatile fatty acids (VFAs), lactic acid, ammonia-N, dry matter (DM), organic matter (OM), metabolizable energy (ME), crude protein (CP), ether extract (EE), ADF and NDF. The aerobic stability of silage was determined by opening jars on day 60 and putting silage in an aerobic environment until day 65. After 3 months of ensiling the 210 l drums were opened, sampled and analysed as for the laboratory scale silos. Silages were fed to 24 South African Dorper lambs (n = 8/treatment) weighing 20.6 ± 0.62 kg to determine intake in a 63-day experimental period. Results from the small silos showed that the inoculants decreased (P<0.05) pH, butyric acid and ammonia-N while increasing WSC, lactic acid and acetic acid compared to the control silage. Aerobic stability of the silage was improved with inoculation as indicated by lower (P<0.05) CO2 production when compared with the control silage. Furthermore, the control silage showed a rise in pH and a changed decline in lactic and acetic acid concentrations when exposed to air, as compared to the inoculated silages. Inoculants did not affect DM, pH, OM, CP, ME, EE, ADF and NDF contents of the silage from 210 l drums. However, bacterial inoculants increased (P<0.05) WSC, lactic acid and acetic acid, while reducing butyric acid and ammonia-N compared to the control. Lambs fed the LFLB inoculated silage had higher (P<0.05) intakes of DM, OM and CP, higher final body weights and average daily gains (ADGs) compared to the other treatments. It was concluded that both bacterial inoculants improved fermentation dynamics and aerobic stability of whole crop maize silage, and improved lamb performance occurred when LFLB inoculated whole crop maize silage was fed.