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21.
Following the rapidly expanding dairy enterprise, mastitis has remained the most economically damaging disease. The objective of this study was mainly to investigate the in vitro antibacterial activities of ethanol extracts of Combretum molle (R.Br.Ex.G.Don) Engl & Diels (Combretaceae) against antibiotic-resistant and susceptible Staphylococcus aureus and Streptococcus agalactiae isolated from clinical cases of bovine mastitis using agar disc diffusion method. The leaf and bark extracts showed antibacterial activity against S. aureus at concentrations of 3 mg/ml while the stem and seed extract did not show any bioactivity. Although both leaf and bark extracts were handled in the same manner, the antibacterial activity of the bark extract against the bacterial strains had declined gradually to a lower level as time advanced after extraction. The leaf extract had sustained bioactivity for longer duration. The susceptibility of the bacteria to the leaf extract is not obviously different between S. aureus and S. agalactiae. Also, there was no difference in susceptibility to the leaf extract between the antibiotic-resistant and antibiotic-sensitive bacteria. Further phytochemical and in vivo efficacy and safety studies are required to evaluate the therapeutic value of the plant against bovine mastitis.  相似文献   
22.
This study estimates the carbon stock of Banja Forest which is natural and dry Afromontane forest type in Banja District, northwest of Ethiopia. A systematic sampling method was used to identify each sampling point through the Global Positioning System. A total of 63 plots measuring 20 × 20 m were employed to collect tree species and soil data. Losses on ignition and the Walkley–Black method were used to estimate biomass and soil carbon stock, respectively. The carbon stock of trees was estimated using an allometric equation. The results revealed that the total carbon stock of the forest was 639.87 t/ha whereas trees store 406.47 t/ha, litter, herbs, and grasses (LHGs) 2.58 t/ha and soil 230.82 t/ha (up to 30 cm depth). The carbon pools’ carbon stock variation with altitude and slope gradients were not significant (p > 0.05) which was similar to other previous studies. The Banja Forest is a reservoir of high carbon and thus acts as a great sink of the atmospheric carbon. It can be concluded that the Forest plays a role in climate change mitigation. Hence, it should be integrated with reduced emission from deforestation and degradation (REDD+) and the clean development mechanism (CDM) of the Kyoto Protocol to catch monetary benefits.  相似文献   
23.
Sorghum, Sorghum bicolor (L.) Moench is an important food security crop widely grown by smallholder farmers in sub-Saharan Africa (SSA), including Ethiopia. In SSA, the potential of sorghum production and productivity has not been realised due to an array of constraints. Colletotrichum sublineolum disease is one of the main biotic constraints causing significant yield losses. The objectives of this study were to assess farmers’ perception, preferences and constraints to sorghum production and productivity in western Ethiopia, and to identify key drivers for anthracnose resistance breeding. A participatory rural appraisal study was undertaken in six selected districts in the East Wellega and West Shewa Administrative Zones in Ethiopia. Data were collected through structured questionnaires involving 165 respondent farmers. Further focus group discussions were held with 180 farmers and development agents. Sorghum is the third most preferred cereal crop after Eragrostis tef and Zea mays in western Ethiopia. About 79% of interviewed farmers cultivated sorghum during the study season. Farmers perceived that sorghum production is constrained by anthracnose disease, bird attack, loose smut and covered smut diseases. The most important farmer-preferred traits in sorghum varieties in the study areas were anthracnose resistance and tolerance to bird attack. Breeding sorghum varieties with the farmer-preferred traits is an important consideration to enhance productivity and adoption of improved sorghum cultivars in western Ethiopia.  相似文献   
24.
One hundred and eighty‐two microsatellites or simple‐sequence‐repeat (SSR) markers for Macrophomina phaseolina were developed. These were tested on 24 isolates of M. phaseolina obtained from seven plant species, and the genetic variation of isolates was studied in relation to potential biological processes that could be affected in this fungus. A total of 120 SSR markers were polymorphic, amplifying >90% of the 24 isolates tested. Thirty percent of the markers showed multiple alleles on individual samples. A large number of markers showed unique alleles in isolates collected from pumpkin and snap bean. DNA sequences corresponding to 43 markers had significant hits on blast x and/or blast2go , and the polymorphism of 36 of those markers showed specific allele patterns for one or more plant host origin of the isolates. Additional tests on growth rate and copper resistance of the isolates identified markers that could be related to those traits. In addition, 27 markers were monomorphic and amplified all 24 isolates. Whereas polymorphic markers can be used for population genetics studies of M. phaseolina, the group of 27 monomorphic markers could help in the fast identification of this species in clinical specimens. The SSR markers developed here will enrich the limited molecular marker resource in M. phaseolina and could be used as the basis for more in‐depth studies of the host‐pathogen interactions of M. phaseolina.  相似文献   
25.
A study was carried out to understand the needs and perception of goat keepers in selected areas of Ethiopia in order to identify the breeding objectives, traits of preference, and production constraints that may be required in designing improvement programs. The study was conducted in three districts (Bati, Meta, and Kebri-Beyah) representing the lowland crop–livestock (LLCL), highland cereal–livestock (HLCL), and pastoral/agropastoral (P/AP) systems, respectively. The study targeted the three goat types (Bati, Hararghe Highland, and Short-eared Somali) found in Ethiopia. Households in all systems considered meat production, milk production, and income generation as major purpose of keeping goats. However, those in the low rainfall and arid environments of P/AP systems gave high ranking to adaptability to harsh environments and also to building social and religious values. In LLCL and HLCL systems, goat skin and manure were more valued than in P/AP systems. Principally, in P/AP systems, the awareness of households to skin utilization and marketing was very low. Despite diverse multiple breeding objectives identified, household breeding practices were affected by constraints related to disease prevalence, feed shortage and water scarcity, and lack of awareness on skin management, utilization, and marketing. Thus, designing and implementing of sustainable goat improvement programs is an overriding priority and should take into account the breeding objectives and knowledge of goat keepers in all production systems. Along with the breed improvement, a strategy should also be devised to enhance the utilization and marketing of goat skin at all levels of production.  相似文献   
26.
A total of 3600 entries of tef [Eragrostis tef (Zucc.) Trotter] germplasm collections representing 36 populations from six regions of Ethiopia were evaluated for phenotypic diversity in six qualitative and phenologic characters. High values of Shannon–Weaver diversity index ( ) were recorded for most characters in each population. Monomorphism was high for anther color (purple) and panicle form (loose). Larger variances for were obtained among regions than among populations within a region from hierarchical analysis of variance. Significant (P<0.05) to highly significant (P<0.01) t-values were observed among values of some regions for seed color, panicle form and days to maturity. A substantial level of variance (P<0.05) was obtained for populations within altitudinal zones only for days to maturity. Altitudinal zones exhibited similar levels of diversity across characters for these collections. Generally, considerable variations important for tef improvement work have been observed and regions with highest diversity for some traits have been suggested for future in situ or ex situ germplasm conservation works. Although similar mean diversity indices were obtained among regions, they were non overlapping.  相似文献   
27.
One thousand and eighty tef, Eragrostis tef (Zucc.) Trotter, entries representing 36 populations collected from six central and northern regions of Ethiopia were evaluated at Debre Zeit Agricultural Research Center during the 1995 main season to assess the quantitative trait diversity in the germplasm with respect to collection regions and altitude zones. Hierarchical analysis of variance showed large (p 0.01) variations within populations, and among populations within regions and altitude zones in all the 14 traits studied. The variations among regions were significant (p 0.05) for number of main shoot culm nodes, and panicle branches and spikelets. But only days to maturity, number of culm nodes, diameters of the two basal culm internodes, and harvest index depicted discernible (p 0.05) clinal variability. The 36 populations clustered into six major (75% similarity level) groups consisting of two up to 15 populations. Five principal components (PCs) explained about 81% of the entire phenotypic diversity among the populations. Of these, the first three PCs accounted for about 65% of the gross variance. About 31% of the total variance explained by the first PC alone originated chiefly from variability in main shoot panicle grain yield and length, culm length and diameter of the two basal culm internodes. Likewise, about 23% the variance accounted for by the second PC was due mainly to variations in grain and shoot phytomass yield/plant, and harvest index. Overall, the study demonstrated that tef is a highly versatile crop species and the enormous wealth of quantitative trait diversity in the germplasm indicates immense potential for the genetic improvement of the crop through breeding.  相似文献   
28.
29.
Eighteen Arsi-Bale (local) and 18 Boer?×?Arsi-Bale (crossbred) male goats, initially approximately 10 months of age, were used in a 12-week experiment to investigate potential interactions between genotype and nutritional plane in growth performance, carcass and skin characteristics, and mass of non-carcass components. Grass hay (6.7% crude protein and 71.9% neutral detergent fiber) was consumed ad libitum supplemented with 150, 300, or 450 g/day (dry matter; low, moderate, and high, respectively) of a concentrate mixture (50% wheat bran, 49% noug seed cake, and 1% salt). Initial body weight was 20.7 and 14.0 kg for crossbred and local goats, respectively (SE = 0.36). Hay dry matter intake was greater (P < 0.05) for crossbred vs. local goats (461 and 429 g/day) and similar among concentrate levels (438, 444, and 451 g/day for high, moderate, and low, respectively; SE = 4.7). Average daily gain was greater (P < 0.05) for crossbred than for local goats (36.6 and 20.8 g) and differed (P < 0.05) among each level of concentrate (43.7, 29.6, and 12.8 g for high, moderate, and low, respectively). Dressing percentage was similar between genotypes (41.1% and 41.1% live body weight for crossbred and local goats, respectively; SE = 0.59) and greater (P < 0.05) for high vs. low (43.5% vs. 38.7% live body weight). Carcass weight differed (P < 0.05) between genotypes (9.23 and 6.23 kg for crossbred and local goats, respectively) and high and low (8.80 and 6.66 kg, respectively). Carcass concentrations of physically dissectible lean and fat were similar between genotypes and high and low concentrate levels. There were few differences between genotypes or concentrate levels in other carcass characteristics such as color and skin properties. Relative to empty body weight, the mass of most non-carcass tissues and organs did not differ between genotypes. However, the low concentrate-level mass of omental-mesenteric fat was greater (P < 0.05) for local vs. crossbred goats (1.06% vs. 0.54% empty body weight, respectively). In conclusion, growth performance and carcass weight advantages from crossing Boer and Arsi-Bale goats were similar with a low-quality basal grass hay diet regardless of level of supplemental concentrate.  相似文献   
30.
Anthelmintic treatment (A), feed supplementation (F), anthelmintic and feed supplementation (A+F) or traditional management (Control) was given to 166 pregnant female donkeys in three localities (Holetta, Debre Zeit and Adami Tulu) in Ethiopia during an on-farm study. Treatments started during the last trimester of pregnancy and continued until 6 months after parturition when the foals were weaned. The same treatments were administered to foals once they reached 1 month of age. Live weights of adults and foals were measured throughout the study along with work output of adult donkeys and survival to weaning of the foals. Faecal worm egg counts (FEC) and blood packed cell volumes (PCV) were recorded monthly. When applied alone, anthelmintic treatment (A) or feed supplementation (F) had no significant effect on live weight gain or foal survival. However, when combined, anthelmintic and feed supplementation (A+F) significantly (p<0.05) improved both live weight gain in adults and foals and foal survival. Workout was not affected by any of the treatments. Treatments A and A+F resulted in a highly significant (p<0.001) reduction in FEC in all three localities during the course of study and for at least 6 months after the last dose of anthelmintic in one of the study areas (Holetta). None of the treatments had any significant effect on PCV. Donkey owners in Ethiopia should be encouraged to adopt both anthelmintic treatment and feed supplementation if they expect tangible benefits in animal performance.  相似文献   
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