- Ethiopia
Tessema Zewdu
Haramaya university, Livestock Production and Range Land Managment, Department Member
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The objectives of the study were to assess current vegetation diversity in the rangeland and its effect on the livestock and socio-economics of the pastoralists. Vegetation data were collected from 72 sample plots laid on the four... more
The objectives of the study were to assess current vegetation diversity in the rangeland and its effect on the livestock and socio-economics of the pastoralists. Vegetation data were collected from 72 sample plots laid on the four transects. The size of the main plot was 20 m x 20 m for tree species. Socio-economic data were analyzed using SPSS version 21 software packages. A total of 75 species of vascular plants belonging to 60 genera and 26 Families were identified from 72 plots. Fabaceae and Poaceae were found to be the dominant families. The Shannon diversity index of the vegetation was 2.10, and evenness index was 0.50, total basal area calculated was 3.25 m2/ha for tree plants species. These studies indicated that most tree species were identified to have poor regeneration status, while shrub species had good regeneration status; which means expansion of unpalatable shrub species and the indicator of bush encroachment in the study area. In the study area, rangeland vegetation...
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The toxicity of ultrafine particles (UFPs) on blood pressure (BP) has not been well studied. We aimed to evaluate the associations of long-term UFP exposure with different components of BP and the risk of prehypertension/hypertension. We... more
The toxicity of ultrafine particles (UFPs) on blood pressure (BP) has not been well studied. We aimed to evaluate the associations of long-term UFP exposure with different components of BP and the risk of prehypertension/hypertension. We included a total of 24 845 Chinese adults (18–74 years old) in a cross-sectional survey (Liaoning province, China). The 4 year (2006–2009) average concentrations of UFP was estimated using a chemical transport model. We measured systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and pulse pressure (PP), prehypertension and hypertension. We used a generalized linear mixed model to examine the associations while controlling for important individual covariates. One unit (1 μg m−3) increase in UFP was associated with an increase in SBP of 1.52 mm Hg [95% confidence interval (CI): 0.48–2.55], DBP of 0.55 mm Hg (95% CI: 0.01–1.08) in DBP, MAP of 0.92 mm Hg (95% CI: 0.23–1.61) and PP of 0.62 mm Hg (95% CI: 0.05–1.20...
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To evaluate the dry matter (DM) yield, relative yield, relative total yield, aggressivity index and relative crowding coefficient, stability and chemical composition of grass-legume mixtures, an experiment was conducted in a randomised... more
To evaluate the dry matter (DM) yield, relative yield, relative total yield, aggressivity index and relative crowding coefficient, stability and chemical composition of grass-legume mixtures, an experiment was conducted in a randomised complete block design with 3 replications. Chloris gayana, Panicum coloratum, Phalaris aquatica, Desmodium uncinatum and Medicago sativa were planted as both pure stands and grasslegume mixtures in the first week of June 1996 to give 11 treatments, and observations continued for 3 years. The highest DM yields were obtained from pure Chloris and Panicum plus 4 mixtures: Chloris-Medicago, Chloris-Desmodium, Panicum-Medicago and Panicum-Desmodium mixtures, with 13–15 t/ha per year in Years 2 and 3. Phalaris and its mixtures yielded well in the first year, but declined steadily after that. The relative total yields of mixtures were greater than ‘unity’, indicating that the DM yields of mixtures were higher than those of an average of the pure stands. The ...
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Extreme climatic events significantly limit livestock performance in semiarid tropics. We assessed the effect of El-Nino-Southern Oscillation (ENSO) rainfall variability episodes on livestock population dynamics of pastoral communities in... more
Extreme climatic events significantly limit livestock performance in semiarid tropics. We assessed the effect of El-Nino-Southern Oscillation (ENSO) rainfall variability episodes on livestock population dynamics of pastoral communities in Shinile zone of eastern Ethiopia. Rainfall and ENSO data from 1984-2015 were collected from the National Meteorology Agency of Ethiopia and National Oceanic and Atmospheric Administration, respectively. Future rainfall trend was predicted with MarkSim (RCP 4.5 General Circulation Model). Livestock population was collected from Ethiopian Central Statistical Agency and the respective study zone. The analysis of rainfall data revealed that there was higher inter-annual rainfall variability under pastoral communities during studied years. Cattle and sheep had positively associated (P 0.05). Cattle mortality and off-take rate had a significant negative relationship with ENSO rainfall variability. Hence, ENSO rainfall variability has affected livestock p...
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In vitro dry matter digestibility (IVDMD) as well as in sacco rumen dry matter degradability (DMD) and nitrogen degradability (ND) studies of Napier grass (Pennisetum purpureum) were carried out using a 3 3 factorial experiment arranged... more
In vitro dry matter digestibility (IVDMD) as well as in sacco rumen dry matter degradability (DMD) and nitrogen degradability (ND) studies of Napier grass (Pennisetum purpureum) were carried out using a 3 3 factorial experiment arranged in a randomised complete block design with 3 replications. The treatments were 3 levels of nitrogen (N) fertiliser (0, 46, bacterium Synergistes jonesii is known to degrade these compounds and inoculation of the bacterium into the rumen protects cattle against mimosine and DHP toxicity. We report on the development, production, and storage of an in vitro, fermentor-based, mixed bacterial inoculum, which includes S. jonesii, for administration to cattle. This technique may be applicable to the production and delivery of other live, anaerobic, bacterial inocula for use in animal agriculture.
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This study aimed to determine vegetation structure, species diversity and aboveground herbaceous biomass and browse yields in Borana rangelands of southern Ethiopia. Sampling through random allocation of quadrats within replicated sample... more
This study aimed to determine vegetation structure, species diversity and aboveground herbaceous biomass and browse yields in Borana rangelands of southern Ethiopia. Sampling through random allocation of quadrats within replicated sample plots was undertaken in communally grazed areas, grazing enclosures and rangelands managed by prescribed fire for five years and grazed only post-fire during dry seasons. A total of 57 herbaceous species (24 grasses and 33 non-grasses) and 39 woody species (12 trees and 27 shrubs) were identified. Of the 24 grass species identified, 16.7% were highly desirable, 62.5% desirable and 20.8% less desirable by grazers. Biomass of both trees and shrubs was significantly higher (p < 0.001) in grazing enclosures than in other treatments, whereas herbaceous vegetation biomass was higher, but not significantly, in prescribed fire managed rangeland units. Importantly, fire-managed areas also contained the highest densities of some of the most desirable grassland species, including Cenchrus ciliaris, Chrysopogon aucheri and Digitaria milanijiana. We conclude that in the absence of fire, the increasing prevalence of enclosures in Borana pastoralist systems may be encouraging the proliferation of woody shrubs and trees at the expense of more desirable pasture species.
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Abstract The effect of tree species on understory vegetation, herbaceous biomass and soil nutrients were studied in a semi-arid savanna of Ethiopia. Twenty large trees, from each of the species: Acacia robusta, Ziziphus spina- christi,... more
Abstract The effect of tree species on understory vegetation, herbaceous biomass and soil nutrients were studied in a semi-arid savanna of Ethiopia. Twenty large trees, from each of the species: Acacia robusta, Ziziphus spina- christi, and Balanites aegyptiaca , a total of 60 trees, and 480 samples were used for measuring understory vegetation, herbaceous biomass, and soil nutrients during the study. The inside tree canopies had a higher speciesdiversityand plant abundance than the outside tree canopies. Acacia robusta had a higher number of species and plant abundance in the understory vegetation compared to other tree species. The biomass yield of herbaceous vegetation under the inside canopies of A. robusta was higher than the canopies of other tree species. Similarly, most soil nutrient contents were higher under A. robusta than other tree species, and the inside canopies had a higher soil nutrient contents compared to outside tree canopies. Hence, the presence of larger trees in semi-arid African savannas confirmed to maintain more species composition and diversity of understory vegetation, higher herbaceous biomass and improved soil nutrients. Therefore, conservation of larger tree species is crucial for proper utilization and ecological stability of semi-arid African savannas under the changing climate and global warming.
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Current theories on diversity-disease relationships describe host species diversity and species identity as important factors influencing disease risk, either diluting or amplifying disease prevalence in a community. Whereas the simple... more
Current theories on diversity-disease relationships describe host species diversity and species identity as important factors influencing disease risk, either diluting or amplifying disease prevalence in a community. Whereas the simple term 'diversity' embodies a set of animal community characteristics, it is not clear how different measures of species diversity are correlated with disease risk. We therefore tested the effects of species richness, Pielou's evenness and Shannon's diversity on bovine tuberculosis (bTB) risk in cattle in the Afar Region and Awash National Park between November 2013 and April 2015. We also analysed the identity effect of a particular species and the effect of host habitat use overlap on bTB risk. We used the comparative intradermal tuberculin test to assess the number of bTB-infected cattle. Our results suggested a dilution effect through species evenness. We found that the identity effect of greater kudu - a maintenance host - confounde...
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Ecological studies have frequently stressed that the availability of seeds in the soil is important for the recovery of semi-arid rangelands. However, the crucial role of soil seed banks has not been incorporated into rangeland models to... more
Ecological studies have frequently stressed that the availability of seeds in the soil is important for the recovery of semi-arid rangelands. However, the crucial role of soil seed banks has not been incorporated into rangeland models to understand vegetation states and transitions in semi-arid rangelands. We developed and evaluated a novel model to show that the availability of seeds in the soil seed banks as a function of plant cover can trigger transitions from perennial to annual grasses and from annual grasses to bare soil with increasing grazing pressure. The model indicates that when grazing pressure is low, a high cover of perennial grasses and a large soil seed bank of these grasses may be present, whereas annual grasses with their seeds in the soil appear with increasing grazing. When grazing pressure further increases, vegetation cover and the soil seed bank size decline. We found that the positive feedback between plant cover and the size of the soil seed bank depends on seed traits, i.e., longevity and germination rate. This positive feedback is an alternative explanation for a sudden vegetation changes in rangelands, which are often explained by the positive feedback between plant cover and the infiltration rate of rain into the soil. In contrast to this latter positive feedback, our model can explain shifts in vegetation from perennials to annuals and vice versa on different soil types, which are often seen in semi-arid rangelands. Our model contributes therefore to the understanding of vegetation dynamics for the proper management and possible restoration of degraded semi-arid rangelands.
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The re-colonization or recovery of grass species after disappearance due to heavy grazing depends on the presence of persistent soil seed banks that might be accumulated over time from the aboveground vegetation. Moreover, successful... more
The re-colonization or recovery of grass species after disappearance due to heavy grazing depends on the presence of persistent soil seed banks that might be accumulated over time from the aboveground vegetation. Moreover, successful plant recruitment is a function of seed production, seed germination and seedling survival, which can be mechanistically understood through studying the life cycle processes of grass species populations under field conditions. Therefore, we studied the number of germinable seeds, species richness and life-forms in the soil seed banks under light and heavy grazing conditions, and the changes in grass species populations in a semi-arid savanna of Ethiopia. Accordingly, a total of 103 species (15 perennial and 29 annual grasses, 6 legumes, 52 forbs and 1 woody species) emerged from the soil samples collected. Lightly grazed sites had a higher seed density compared with heavily grazed sites. The seed density increased over the first three months of soil sam...
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Abstract A study to determine carbon sequestration potentials and soil attributes was conducted in Borana rangelands of southern Ethiopia under communally grazed areas, grazing enclosures (rangelands enclosed for 20 years for dry season... more
Abstract A study to determine carbon sequestration potentials and soil attributes was conducted in Borana rangelands of southern Ethiopia under communally grazed areas, grazing enclosures (rangelands enclosed for 20 years for dry season grazing) and rangelands managed by prescribed fire for more than five years after fire application. Soil attributes were collected from three soil depths (0–10 cm, 10–20 cm and 20–30 cm) and both aboveground and belowground carbon were estimated in all treatments. Belowground carbon stocks were higher than the aboveground carbon stocks in all management systems in Borana rangelands. Tree and shrub carbon and soil organic carbon stocks were higher (P
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... Fekadu Abate (1999) Assessment of the feed resources base and the performance of draught oxen of the traditional fattening practice of ... Minale Kassie, Mohammad Jabbar, Belay Kassa and Mohammed Saleem (1997) An ex-nate analysis of... more
... Fekadu Abate (1999) Assessment of the feed resources base and the performance of draught oxen of the traditional fattening practice of ... Minale Kassie, Mohammad Jabbar, Belay Kassa and Mohammed Saleem (1997) An ex-nate analysis of inter-cropping food crops with ...
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A survey was conducted in Hamer and Benna-Tsemay districts of the South Omo zone of Ethiopia, with the objectives of assessing the range-livestock management practices and perceptions of the different pastoral groups (Hamer, Benna, and... more
A survey was conducted in Hamer and Benna-Tsemay districts of the South Omo zone of Ethiopia, with the objectives of assessing the range-livestock management practices and perceptions of the different pastoral groups (Hamer, Benna, and Tsemay) towards rangeland degradation. This information is considered to be vital to future pastoral development planning and interventions. The information was gathered through group discussions, personal observations, and using a structured questionnaire where each household was taken as a unit of analysis. The average family size per household was for Hamer = 7.05 for Benna = 7.93 and for Tsemay = 7 with nearly 98.1% of the respondents without any kind of education. All pastoral groups derived their main income from the sale of animals, which was followed by the sale of honey as in the case of Hamer and Tsemay pastoralists. The average livestock per household was 25.7, 10 and 2.8 tropical livestock unit (TLU) cattle, goat and sheep, respectively. T...
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... Pennisetum purpureum, Schum. Annals of Agricultural Science, University of Ain Shams, Egypt 28: 607625. Kariuki JN, Gachuiri CK, Gitau GK, Tamminga S, Van Bruchem J, Muia JMK and Irungu KRG 1998. Effects of feeding ...
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... The ranch was established about 40 years ago, for the genetic conservation of Borana cattle and for distributing breeding bulls and heifers to the surrounding communities through crossbreeding with Holstein Friesian and Jersey cattle... more
... The ranch was established about 40 years ago, for the genetic conservation of Borana cattle and for distributing breeding bulls and heifers to the surrounding communities through crossbreeding with Holstein Friesian and Jersey cattle (Mekuria et al., 1999). ...
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The management influence on carbon sequestration potential of different land use types are least known at the national level. This research was conducted to assess the impact of area exclusion on carbon sequestration potential in the two... more
The management influence on carbon sequestration potential of different land use types are least known at the national level. This research was conducted to assess the impact of area exclusion on carbon sequestration potential in the two land use systems: protected natural vegetation (PNV) and communal grazing land (CGL). Data of vegetation, litter, and soils were collected using systematic sampling methods, laying 19 transects and 62 quadrats each with 20 m × 20 m for trees, 5 m × 5 m sub-quadrats for shrubs, and 1 m × 1m sub-quadrats for herbs/grasses, litter biomass, and soil sample. Aboveground biomass carbon (AGC), belowground biomass carbon (BGC), soil organic carbon (SOC), and total carbon stock (TC) were estimated using allometric equations. The mean difference level of carbon stocks (P < 0.05) of the two land use systems was tested through unequal variance t-test using R-software. The mean above ground and below ground carbon stock of PNV, 21.05 ton/ha, 10.39 ton/ha, was higher than CGL, 15.31 ton/ha, 7.65 ton/ha, respectively. The average values of SOC was 16.60 ton/ha from PNV and 13.76 ton/ha from CGL. The mean value of SOC was higher at the PNV than CGL and significantly different (P < 0.05). The total carbon stock estimate of PNV and CGL were 50.74 ton/ha and 37.11 ton/ha, respectively, which is significantly different (P < 0.05). We concluded that, establishment of PNV as the best practice of restoration programs through exclusion of livestock from free grazing and human interference provides cost effective mechanism that yields a high carbon sequestration potential with multiple benefits for biodiversity conservation, livelihood support, and climate change mitigation.
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... 2008a, 2008b), and ruminant animals depend predominantly on high-fibre feeds that are deficient in nutrients essential for microbial fermentation during the long dry seasons (Getnet 1999, Tessema and Baars 2004, Mekoya 2008). ...... more
... 2008a, 2008b), and ruminant animals depend predominantly on high-fibre feeds that are deficient in nutrients essential for microbial fermentation during the long dry seasons (Getnet 1999, Tessema and Baars 2004, Mekoya 2008). ... 1995, Azage and Alemu 1998, Getnet 1999). ...
Research Interests: Plant Biology and Biology
The study was conducted at Keramile protected open forest of Goro-gutu district, Eastern Ethiopia, with the objective to examine the effects of tree species on the above ground aboveground biomass yield and ground cover of the herbaceous... more
The study was conducted at Keramile protected open forest of Goro-gutu district, Eastern Ethiopia, with the objective to examine the effects of tree species on the above ground aboveground biomass yield and ground cover of the herbaceous plants. Three tree species, Podocarpus falcatus and Juniperus procera from indigenous and Cupressus lusitanica from exotic tree species were used. Twenty large trees from each tree species, a total of 60 trees were selected purposively and 480 samples (four quadrats under and outside canopy in four directions for each tree) of herbaceous plants were collected. The results of the current study showed that tree species, canopy cover and their interactions had significant (P 0.05) found between J. procera and C. lusitanica trees. The above ground aboveground biomass yield and ground cover obtained outside canopy was significantly higher than under canopy cover of the three tree species examined. The overall result showed that tree canopy cover strongly...
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The shortage of arable land and shortage of livestock feed specially quality feed resources are major constraints in East Hararghe Zone. Thus, a field study was conducted to evaluate an early maturing sorghum varieties and cowpea Lines... more
The shortage of arable land and shortage of livestock feed specially quality feed resources are major constraints in East Hararghe Zone. Thus, a field study was conducted to evaluate an early maturing sorghum varieties and cowpea Lines intercropping for both food and feed production at Fedis Agricultural Research Center, eastern Ethiopia in 2018/19 cropping season. Two cowpea varieties (lines) (9333 and 9334) were intercropped with three varieties of early maturing sorghum (Teshale, Birhan and Melkam) and compared with sole cropping of all the varieties, which were laid out in a randomized complete block design with three replications. The analyzed result showed the NDF content was significantly different (p < 0.05) among intercropped and sole sorghum the maximum NDF was recorded from sole sorghum Teshale (69.56%) and the minimum sorghum Birhan + cowpea (9333) (57.75%) and the Intercropping sorghum improved the CP of sorghum stover mean from sole (5.31%) to intercropped (6.03%). ...
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This study was conducted to evaluate the forage production and farmers preference as livestock feed under farmer’s conditions in West Hararghe Zone of Oromia region, Ethiopia. Four improved Napier grass cultivars (ILRI cultivar number:... more
This study was conducted to evaluate the forage production and farmers preference as livestock feed under farmer’s conditions in West Hararghe Zone of Oromia region, Ethiopia. Four improved Napier grass cultivars (ILRI cultivar number: 16801, 16800, 16798, and 16840) and local check were planted in a Randomized Complete Block Design (RCBD) with six replications during the main cropping season of 2018/19. The dry matter (DM) yield, fresh biomass yield, plant height, leaf length and leaf-stem ratio and other agronomic data were measured at harvest. Farmers preference of the Napier grass cultivars as livestock feed was collected through visual and hand evaluation of the multiple ranking criteria of the cultivars based on phonological nature. The results shows that, ILRI cultivar no. 16800 was higher (P 3), as an indicator for livestock feed. From this study, it is concluded that Napier grass cultivars No. 16800, 16840 and 16801 were found promising in terms of agronomic traits, DM yiel...
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An experiment was conducted to assess the agronomic attributes, dry matter (DM) yield, biological potential and economic viability of grass-legume mixtures at Haramaya University in Ethiopia during 2004 and 2005. Chloris gayana, Panicum... more
An experiment was conducted to assess the agronomic attributes, dry matter (DM) yield, biological potential and economic viability of grass-legume mixtures at Haramaya University in Ethiopia during 2004 and 2005. Chloris gayana, Panicum coloratum, Melilotus alba and Medicago sativa were planted as pure stand and in mixtures using 50:50, 33: 67, 67: 33, 25: 75 and 75: 25 seed rate proportion to give 24 treatments in a randomised complete block design with 3 replications. There were significant (P < 0.05) differences in the number of seedlings per m2 (SLM), row cover, number of tillers per m2, days to 50% flowering (DF 50%) of the grass components among the grass/legume combinations due to seed rate proportions. Moreover, SLM, the number of branches per m2, the height of the plant at harvest, DF 50% of the legume components were significantly (P < 0.05) affected among the mixtures due to seed rate proportions. There was a significant (P < 0.05) difference in the DM yield of pure stand grasses and legumes, and their mixtures due to seed rate proportion. Significant (P < 0.05) effects were also observed on the relative yield (RY), the relative total yield (RTY), the relative crowding coefficient (RCC) and the aggressivity index of both the grass and legume components and their mixtures due to different seed rate proportions throughout the study. The two years’ mean RTY of all grass-legume mixtures were greater than one (range: 1.23-2.11) and Chloris mixed with Melilotus and Medicago with 67: 33 seed rate proportion had higher RTY than other mixtures. Both the grass and legume components in the mixture produced mean RCCs values in excess of unity and almost equal values in both components, indicating that all yielded better in the mixture than expected in pure stands at different seed rates. Chloris gayana mixed with Melilotus alba at 50:50 and 33:67 seed rate proportion gave higher DM yield, average net return/ha and average net return/ha/yr compared to pure stand grasses and legumes and their different mixtures during the study. Therefore, to alleviate the feed scarcity in the area; these grass-legume mixtures could be introduced to smallholder farms. In addition, further studies on animal performances should be conducted using feeding trials and under grazing conditions.
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This paper aimed to assess the vegetation structures and diversities in grazing land of the Abijata Shalla Lake National Park in Ethiopia. The stratification was done before sampling based on grazing intensity and the random sampling... more
This paper aimed to assess the vegetation structures and diversities in grazing land of the Abijata Shalla Lake National Park in Ethiopia. The stratification was done before sampling based on grazing intensity and the random sampling techniques were used. The two grazing intensities* 12 sampling site* five plots per sample site=120 samples were used. The 10m*10m, 5m*5m and 1m*1m plot size were used for trees, shrubs and herbaceous respectively. The indivudal abundance, density and important value index of each plant species were estimated. The height of woody vegetation was estimated by clinometers and the DBH at 1.3m and 0.3m by caliper for tree and shrubs respectively. The proportions of desirable and undesirable species, richness and diversity with the life form of herbaceous were determined. Then, the fresh weight of biomass was clipped and sub-sample were oven dried at 105 o C for 24hr to determine the dry matter. A total of 64 species, that belonged into 27 families were ident...
Bovine tuberculosis (bTB) infection is generally correlated with individual cattle's age, sex, body condition, and with husbandry practices such as herd composition, cattle movement, herd size, production system and proximity to... more
Bovine tuberculosis (bTB) infection is generally correlated with individual cattle's age, sex, body condition, and with husbandry practices such as herd composition, cattle movement, herd size, production system and proximity to wildlife-including bTB maintenance hosts. We tested the correlation between those factors and the prevalence of bTB, which is endemic in Ethiopia's highland cattle, in the Afar Region and Awash National Park between November 2013 and April 2015. A total of 2550 cattle from 102 herds were tested for bTB presence using the comparative intradermal tuberculin test (CITT). Data on herd structure, herd movement, management and production system, livestock transfer, and contact with wildlife were collected using semi-structured interviews with cattle herders and herd owners. The individual overall prevalence of cattle bTB was 5.5%, with a herd prevalence of 46%. Generalized Linear Mixed Models with a random herd-effect were used to analyse risk factors of c...
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Introduction: Pastoral livestock share grazing areas and watering points with wildlife around the protected areas in Eastern Africa. This causes a high degree of livestock-wildlife interactions, leading to conflicts between the local... more
Introduction: Pastoral livestock share grazing areas and watering points with wildlife around the protected areas in Eastern Africa. This causes a high degree of livestock-wildlife interactions, leading to conflicts between the local community and park staff. Thus, understanding the perception and attitude of local people towards livestock-wildlife interaction is very crucial to optimize both livestock production and biodiversity conservation in protected areas. This paper presents the perception and attitude of local community towards livestock-wildlife interactions around Awash National Park (ANP), Ethiopia.