| This study evaluated the effects of Lactobacillus plantarum,Lactobacillus buchneri or Enterococcus faecalis added alone or in combination as inoculants on the quality of whole corn silage by the laboratory methods,microbiological techniques,chemical composition analysis and in vitro two-stage digestion.Chemical composition,microbiological counts and aerobic stability were studied.In Expt.1,the effects of different doses of LactobaciUus buchneri added at 1×105 cfug-1FM(L1), 1×106cfug-1FM(L2),1×107cfug-1FM(L3) to whole corn silage on the fermentation and aerobic stability of the silage were evaluated on the first day(S1),48 h(S2) and 96 h(S3) after harvest.The results showed that longer delay periods after harvest led to increase the fungal populations,higher pH,L. buchneri inhibited yeasts and molds in the silage,improved aerobic stability of the silage effectively. The concentrations of lactic acid,acetic acid or ammonia-N were unaffected by different doses of L.buchneri.The silage had greater concentrations of lactic acid and lower concentrations of NH3-N on S1 than that on S2 or S3.The concentrations of water soluble carbohydrates(WSC),NDE ADE EE,CP and DMD of the silage(65 d after ensiling) were unaffected by L.buchneri.The silage treated with the enzyme had greater concentrations of WSC(P＜0.05) than that of the other treatments on S2.Increasing doses of L.buchneri improved aerobic stabilityof silage(320 d after ensiling) significantly on S1 or S3. The silage(180 d after ensiling) treated with L2 was more stable aerobically than L1 or L3 on S2. Longer delay periods before ensiling tended to reduce silage quality.L.buchneri suppressed fungi such as yeasts and molds in the silage,improved aerobic stability of the silage effectively.In Expt.2,the effects of Lactobacillus plantarum,Lactobacillus buchneri or Enterococcus faecalis added alone on the quality and the microbiological counts of whole corn silage ensiled after sterilazion were evaluated.The microbiological counts were as follows:the peak growth of E.faecalis, L.plantarum and L.buchneri occured on the sixth,seventh and half of day,ninth day respectively with the microbiological counts of 8.78 log(cfu g-1FM),9.26 log(cfu g-1 FM) and 9.18 log(cfu g-1 FM).The microbiological counts of E.faecalis,L plantarum and L.buchneri were significantly different(25-60 d of ensiling) with the rank as follows:Enterococcus faecalis＞L,plantarum＞L.buchneri.The pH values of the E.faecalis,L.plantarum,L.buchneri treated silage were significantly different with the rank as follows:L.plantarum＞E.faecalis＞L.buchneri after 4.5 d of ensiling,L.buchneri＞L. plantarum＞E.faecalis during 6-25 d of ensiling,E.faecalis＞L.buchneri＞L.plantarum during 30-60 d of ensiling.The concentrations of NH3-N of the silage treated with E.faecalis,L.plantarum,L. buchneri were significantly different on 30 or 60 d of ensiling:the L.buchneri-treated silage had the highest concentration of NH3-N,and the L.plantarum-treated silage had a higher NH3-N concentration than that of the E.faecalis-treated silage.In Expt.3,the effects of different combinations of two lactic acid bacteria on the quality and the microbiological counts of whole corn silage were determined.The results showed that the highest counts of lactic acid bacteria occurred during 7.5-9 d of ensiling.The counts of lactic acid bacteria were significantly different during 9-60 d of ensiling with the rank as follows:L.buchneri+L,plantarum＜E. faecalis+L,buchner＜L.plantarum+E,faecalis.The pH values of the silage were significantly different during 4.5-60 d of ensiling with the lowest pH value observed for the silage treated with L. buchneri+L,plantarum,and the pH value was lower in the silage treated with E.faecalis+L,buchner than that in the silage treated with L.plantarum+E,faecalis.The silage treated with L.buchneri+L. plantarum had the highest concentration of lactic acid(P＜0.05) on 30 or 60 d of ensiling,and the silage treated with E.faecalis+L,plantarum had a significantly higher concentrationt of lactic acid than the silage treated with L.plantarum +L.buchneri on 30 d of ensiling,and the silage treated with E. faecalis+L,buchneri had a significantly higher concentrationt of lactic acid than the silage treated with E.faecalis+ L.plantarum on 60 d of ensiling.The silage treated with L.plantarum+E.faecalis contained more acetic acid than the silage treated with E.faecalis+L,buchneriand,but less than that treated with L.plantarum+L.buchneri on 30 d of ensiling(P＜0.05).The silage treated with L. plantarum+L.buchneri contained more acetic acid than that treated with E.faecalis+L,buchneri,but less than that treated with L.plantarum+ E.faecalis significantly on 60 d of ensiling(P＜0.05).The concentrations of NH3-N and WSC of the silage were significantly different with the rank as follows:L. buchneri+L.plantarum＞E.faecalis+L,buchneri＞L.plantarum+E.faecalis.The NDF content of the silage treated with L.buchneri+L.plantarum was lower than that treated with E.faecalis+L. buchneri or L.plantarum+E.faecalis.In conclusion,the results indicated that the combination of L. buchneri+L.plantarum was preferred over the other combinations for whole corn silage.
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