Экологическая и аналитическая токсикология

Feed Resources Gozamen District, East Gojjam Zone, Amhara Region

Abstract

Gashe A, Zewdu T and Kassa A

The study was conducted in Gozamen district of East Gojam Zone of the Amhara region to assess the major feed resources, the grazing land condition, the floristic composition, and biomass yields of herbaceous species to generate baseline information which can be used for future management of grazing land resources and to identify feed constraints in the area. The survey data was collected by interviewing a total of 120 households by random selection of two rural kebeles from three altitudes (high, mid and low). To assess grazing land condition, the district was stratified into three altitudes (high, mid and low altitudes). From each altitude, communal and enclosed grazing areas were selected randomly. From each altitude 8 composites and 12 composites from enclosed and 12 composites from communal grazing for herbaceous vegetation and 4 transects from each altitude of communal grazing were selected. Thus, a total of 72 quadrats were used for herbaceous and 12 transects for woody species. For the natural pasture condition assessment, analyses of variance (ANOVA) were carried out by the General Linear Model (GLM) procedure of SAS. Mean separation was tested using the least significant difference. The main feed resources to the livestock in all altitudes were natural pasture, crop residues and stubble grazing. During dry season, crop residues was the first livestock feed source followed by natural pasture in all altitudes. However, during wet season, natural pasture was the first livestock feed source followed by crop resides in all altitudes. In terms of dry matter (DM) crop residues contributed the highest proportion (66.7%) of the total feed sources. The DM obtained from crop residues significantly varied (P<0.05) among the altitudes. The total annual estimated available feed supply to maintain the livestock in the area satisfied only 79.4%. The conservation of feed resources in the form of hay in high, mid and low altitudes was 38.5, 80, and 22.5%, respectively. But, none of the respondents used silage in the study area due to lack of knowledge how to make it. In the district, a total of 21 herbaceous species were identified, from these 57, 24 and 19% were grasses, legumes and other species, respectively. Based on dry matter of biomass, Medicago polymorpha in high and mid altitudes and Eleusine floccifolia in low altitude were the dominant species. Altitude and grazing have effects on grazing land conditions and biomass production. The average dry matter yield of grasses, legumes and total biomass had a significant difference among altitudes in enclosed and communal grazing areas. The average dry matter yield of grasses, legumes, and total biomass were higher in enclosed area than communal grazing areas in all altitudes. There were a significant (P<0.01) interaction of altitude and grazing on biomass and species composition. There was positive correlation of species composition, grass species composition and basal cover with biomass. Crop residues and natural pastures are the major feed resources in dry and wet seasons, respectively. The total annual dry matter does not meet the total livestock requirement per annum in district. Further research and development work is recommended to alleviate feed shortage through different options such as development of improved forages and alternative means of crop residue utilization and conservation of feed in the form hay and crop residues.