Abstract:
A study was conducted in Adola Reedde district of Guji zone, to asses and identify the major
grass species, evaluate their chemical composition, in vitro digestibility, and estimate the
biomass yield of the major grass species. A total of 60 key informants taken from the sample
kebeles of three agro- ecologies were interviewed to asses and identify common grasses in
their vernacular name. Sample collection was done in the mid of September for three
consecutive days. A total of 6 rural kebeles were stratified into highland (dega), mid altitude
(woina dega) and lowland (kola) agro-ecologies based on the availability, potential and
accessibility of local grass species and the specific sampling areas in the kebeles were
identified based on slopes of kebeles. The relative feed value (RFV) and dry matter
digestibility (DMD) were calculated using NDF and ADF contents. Spearman’s rank
correlation was used to examine relationships between laboratory results and farmers
perception on grass quality. A total of 15 common grass species were identified and ranked by
farmers according to the species’ preferences to cattle. Cynodon dactylon (L.) Pers),
Cenchrus ciliaris, Sporobolus pyramidalis P. Beauv, Heteropogon contortus (L.) Roem &
Schult and Chrysopogon aucheri were the top five species identified by farmers. The chemical
composition of the grasses significantly (P<0.001) varied between agro-ecology and species.
The CP values range from 5.65% for lowland to 11.3% for highland agro-ecology. Cynodon
dactylon (L.)Pers has the highest while Heteropogon contortus (L.)Roem & Schult exhibited
the lowest CP content. An overall mean value of NDF, ADF and ADL were 66.2%, 45.18%,
and 11.23%, respectively, and IVDMD, ME, and RFV were 44.65%, 6.69%, and 60.97%,
respectively. Total DM yield and DM of individual grass species were significantly (P<0.001)
higher in highland than in the low land agro-ecology. Dry matter yield across agro-ecology
ranged from 92.47±0.04 g m-2-119.41±0.07g m-2 for highland and lowland agro-ecology,
respectively. The effect of intra location transect position was not significantly different
(P>0.05) for DM yield. Generally, the potential of the herbaceous species to be used as feed to
ruminant livestock, particularly in semi-arid areas is decreasing and it is aggravated by
climate change/variability and global warming. Therefore, rangeland improvement has to be
made for conservation of key forage species by use of holistic planned grazing, enclosure, and
balancing the number of livestock so as to enhance the potential of grassland and dry matter
yield of herbaceous species.
