Abstract:
This study was conducted with the objective of evaluating the physiochemical and
fermentation characteristics, feed value and microbial quality of green maize stover
(GMS) and alfalfa mixed silage. To meet the objective GMS and Alfalfa crops were
cultivated and harvested in Arba Minch Agriculture Research Center. The maize grown
was harvested at two the third of milk stage, while the alfalfa was harvested at about
50% of blooming stage. Then the harvested biomasses (GMS and Alfalfa) were chopped
and wilted separately, and mixed proportionally in four levels of treatments (T) and five
levels of replications. The treatments were: T1 (100% GMS), T2 (40% GMS + 60%
Alfalfa), T3 (60% GMS + 40% Alfalfa) and T4 (80% GMS + 20% Alfalfa). After taking
fresh samples for laboratory analysis, all the proportionally mixed treatments were
ensiled anaerobically in a 4.5 kg capacity PVC tube micro silo for 60 days. The
experiment was conducted by completely randomized design with a 4 × 2 (4 levels of
treatments and 2 ensiling days) factorial arrangement. The results for cultivated GMS
and Alfalfa forage during harvesting had 44,778 and 11,815 Kg/ha fresh biomass yield
and 14,611 and 3,140 Kg/ha total dry matter yield respectively. The ensiled GMS and
alfalfa mixed silage after 60 days of fermentation had a positive effect (P <0.05) on
sensory evaluation, physiochemical characteristics, feeding value and microbial count
with increasing the proportion of alfalfa from 20% to 60% in the mixture. The sensory
evaluation revealed that light olive green color, pleasant smell, fairly firm texture and
scattered mold spot in T1 and T4, whereas olive yellow color, almost pleasant smell and
soft texture for T2 and T3 and medium with scattered mold spot in T2 and T3
respectively. The results obtained for T2 after fermentation was showed (P <0.05) better
effect on Ash (11.79), CP (24.78), EE (7.95), DDM (64.46), DMI (2.93), RFV (145.5) and
TDN (64.1) by decreasing GMS from 100% to 40% within the mixture. The results
obtained for pH at 0 day were 5.14, 5.96, 5.76 and 5.49 for fresh sample, T1, T2, T3 and
T4 respectively. The results obtained for pH at 60 days were 3.71, 4.09, 4.01 and 3.85 for
T1, T2, T3 and T4 respectively. The results for microbial count revealed that at day 0
lowest values of TVC (5.79) and Enterobacteriacea (6.79) were recorded for T2 and
Yeast and Mold counts (5.89) for T3 log cfu/g respectively. At 60 day, the highest count
for TVC (6.05) were in T2, Yeast and Mold (4.31) for T1, and Both Enterobacteriacea
and Yeast and mold counts were not detected for T2. It was concluded that, increasing
the proportion of alfalfa at least 60% in the ensiling of GMS mixture had a significant (P
<0.05) effect in chemical composition, physiochemical characteristics, feed digestibility
and microbial count on fermentation quality and for nutrient preservation. Therefore, it
should be better to ensile 40% of green maize stover with 60% of alfalfa to improve feed
value and protein content of the fermented forage feed for animals.
