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A study was conducted to evaluate growth performances of Washera sheep under smallholder production systems in the Yilmanadensa and Quarit districts of the Amhara National Regional State, Ethiopia. Data were collected and analysed on the growth of 690 lambs owned by 110 households from October 2004 to September 2007. Weight (kilograms) of Washera lambs at birth, 1, 3, 6, 9 and 12 months of age was 2.69 ± 0.02, 7.10 ± 0.16, 12.42 ± 0.11, 16.12 ± 0.91, 20.05 ± 0.55 and 23.47 ± 0.68, respectively. Birth weight was significantly (P < 0.05) affected by district, year of birth, parity of the dam, birth type and sex of lamb and by the interaction effect of parity by birth type and parity by sex of lamb. Weaning weight was also affected by year of birth, type of birth and sex of lamb. Yearling weight was affected by only year of birth and sex of birth. The average daily weight gain (ADG; grams) from birth to 30 days, birth to 90 days, 90 to 180 days and birth to 1 year of age was 143.37 ± 13.46, 107.09 ± 2.67, 39.78 ± 9.73 and 60.13 ± 1.89, respectively. Growth rates from birth to 30 and 90 days of age were significantly (P < 0.05) affected by birth year, birth type and sex. ADG from birth to 1 year of age was affected by lamb sex and district. The indigenous Washera sheep had faster growth rate than those sheep breeds of Ethiopia extensively studied thus far. Integrated efforts combining improved nutrition, health and participatory community-based breeding would help the smallholder farmers to utilise and conserve this immense sheep genetic resource of Ethiopia.  相似文献   
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The prevalence and serotypic diversity of Mannheimia [Pasteurella] haemolytica and Pasteurella trehalosi from nasal swabs, sera and abattoir specimens from sheep in the highlands of Wollo, North East Ethiopia was investigated. Prevalence rates of 83% and 75% of these microorganisms were found in the serum samples and nasal swabs, respectively, from apparently healthy sheep. In a local abattoir, 205 lungs were investigated, 34% of which showed pneumonia, from which samples were collected from 51 lungs and the same number of corresponding tonsils. Mannheimia and Pasteurella species were isolated from 59% of these pneumonic lungs and 69% of the respective tonsils. M. haemolytica serotypes accounted for 41 (59%) and P. trehalosi for 11 (32%) of the isolates from the abattoir specimens. The majority (67%) of isolates from nasal swabs were P. trehalosi, M. haemolytica being isolated f rom 4 (13%) of the swabs. M. glucosida was isolated only from the tonsils. The predominant serotypes of the isolates from both the nasal swabs and the abattoir specimens were M. haemolytica A1 (17%) and P. trehalosi T4 (16%) and T3 (13%). P. trehalosi T15 was less commonly encountered, while M. haemolytica A9 and A13 were not isolated. Studies on sera from 100 sheep indicated that antibodies against M. haemolytica serotype A1 (14%) were most common, followed by A5 and A8 (each 10%) and A9 and P. trehalosi T3 (each 9%) and T4 (8%). Antibodies against M. glucosida or serotype A11 occurred in 2% of the sera. Multiple serotypes were common in all types of samples. The importance of including in vaccines the most prevalent serotypes involved in the pneumonia of sheep in the area is discussed.  相似文献   
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The role of seed producer cooperatives (SPCs) in the Ethiopian seed sector and their contribution to seed supply improvement have received attention from researchers, policymakers, and development partners. However, limited work has been done in reviewing and documenting their involvement in the seed sector development. In this paper, we review and discuss the SPCs in the Ethiopian seed sector. Specifically, we reflect on the contribution of SPCs to improving seed availability and access in the country. The current liberal market system of Ethiopia creates new opportunities for growth as successful enterprises, but also brings new challenges, such as more intense competition for smallholder producers. The government policy encourages SPCs to engage in seed business. We draw on scientific literature, reports, white papers, project documents, and websites. The review reveals that the seed sector in Ethiopia consists of three seed systems: formal, informal, and intermediary seed systems. Each seed system has a specific contribution to the delivery of seed to farmers, but they vary in their approach and respective strategies. The SPCs are categorized in the intermediary seed system because they have features of both formal and informal seed systems. They play a key role in meeting seed demand and contribute greatly to seed supply improvement through high-volume production of seed, crop, and variety diversification, and seed delivery to farmers. They produce and market the seed through various market channels, including direct sales to farmers, sales through contractual agreement, and sales directly to institutional buyers. Their contribution to improving the seed supply and seed security has received considerable recognition by policymakers and development practitioners. Therefore, government and development partners should support and strengthen SPCs to maximize their success in the seed business and their contribution to improving the seed supply in Ethiopia.  相似文献   
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Enset root mealybug, Cataenococcus ensete Williams and Matile-Ferrero, (Homoptera: Pseudococcidae) is an economically important pest on enset. Adults and nymphs of overlapping generations feed on the corms and roots of enset and are difficult to control once established. Isolates of Beauveria bassiana (Balsamo) Vuillemin and Metarhizium anisopliae (Metschnickoff) Sorokin that originated from Ethiopia were evaluated for their efficacies against enset root mealybugs under laboratory, pots and field conditions. Of the tested isolates, two strains (FF and PPRC-56) of B. bassiana were found to be highly pathogenic to adults, causing 97 and 100% mortality, respectively 20 days after inoculation under laboratory conditions. On the other hand, the isolates PPRC-56, FF, PPRC-6 and Mm induced mean mortalities of 97, 95, 96 and 83%, respectively, to the adult enset root mealybugs on the pot experiment, and 51.33, 38.67, 29.33 and 19.33% mortality at the first site and 54.00, 42.67, 32.00 and 25.33% at the second site, respectively, in field experiments. The study showed B. bassiana and M. anisopliae can be used in the integrated management of enset root mealybug.  相似文献   
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On-farm survey of farmers' breeding practices, breeding objectives, and selection criteria and on-station feedlot performance evaluation of Washera sheep were undertaken in Ethiopia. The survey revealed that most (79.8%) of the farmers had no breeding ram. The mating system was predominantly uncontrolled. A majority (75.5%) of the sheep owners reported that they herded their sheep flock by mixing with other livestock species mainly with cattle. During grazing, 44.6% of the farmers mix their sheep flock with neighboring sheep flocks. The major sheep production objective was to generate income from the sale of live sheep. Fast growth, appearance, coat color, and pedigree performance were important ram selection criteria, respectively. Ability to breed at early age, pedigree information, mothering ability, and lambing interval were important selection criteria for ewe, respectively. The on-station performance study involved evaluation of feedlot gains and carcass production under five levels of feeding regimes (300, 400, 500, 600, and 700 g day−1 of concentrate feed) for a period of 93 days. The results indicated that the feedlot growth and carcass performance of Washera sheep were very high, with average daily weight gains of up to 126 g and carcass weight of 16 kg, with the optimal level of supplementation for Washera sheep being at 500 g of concentrate per day for a period of 93 days.  相似文献   
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The use of Eucalyptus trees, in association with other plants, has the potential to reduce the growth of neighbouring plants or grasses by competing for resources or releasing allelochemicals that may cause other plants to grow slowly. Our purpose here is to assess whether border planting of Eucalyptus is harmful to the establishment,growth, and production of Cymbopogon winterianus at various distances from tree lines in the Wondo Genet Agricultural Research Center in Southern Ethiopia. Several factors were studied: growth performances and yield of aromatic grasses; soil properties, including total nitrogen,organic carbon, and moisture content; and plant leaf nutrient content(NPK) at various distances away from the Eucalyptus citriodora border line were studied. Chemical compositions of hydro-distilled essential oils obtained from selected C. winterianus grasses leaves were analysed by gas chromatography. Plant height, biomass yield, amount of essential oil yield, and essential oil composition all were significantly affected due to Eucalyptus effect in the first10-m distance as compared to beyond 10 m from the tree border line. There were increases in soil total nitrogen,organic carbon, and moisture content with decreasing distances to the Eucalyptus tree border. The result of plant leaf nutrient content(NPK) differed across treatment and distance. The pot experiment(15 cm 9 20 cm), shoot length,and number of leaves of aromatic plants varied in the degree of inhibition based on the concentration of the aqueous extract. Significantly higher inhibitions of the shoot length and number of leaf parameters were observed when using 25% fresh leaf extract compared to other extract levels.  相似文献   
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The pathogenicity and identity was studied of a field sample (PcE) of crown rust fungus Puccinia coronata collected in Hungary on wild couch grass (Elymus repens) and of a field sample (Psb) of stripe rust (P. striiformis) collected in the Netherlands on California brome (Bromus carinatus). We focused on the analysis of the host susceptibility of cultivated barley (Hordeum vulgare) to both pathogen samples, in direct comparison with an isolate of P. striiformis f.sp. tritici (Pst) and P. striiformis f.sp. hordei (Psh). At the seedling stage 83 % of the barley accessions were susceptible to PcE. At the adult plant stage, cultivated barley was predominantly resistant to this crown rust sample. Morphology, pathogenicity on Hordeum and Bromus and ITS DNA sequence analysis determined that PcE represents a European specimen of P. coronata f.sp. hordei. Sample Psb was pathogenic on 47 % of the cultivated barley at the seedling stage. This is intermediate between the isolates Psh (90 %) and Pst (10 %). Psb and Psh were pathogenic to grasses representing several genera. The host range of the Pst isolate was more narrow. We conclude that Psb is unlikely to represent a genotype of Psh that happened to have colonized B. carinatus, and is likely a distinct form of P. striiformis.  相似文献   
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This paper reports for the first time on farmers’ knowledge, perceptions and management practices of the fall armyworm (Spodoptera frugiperda) in Ethiopia and Kenya. A survey of 343 smallholder maize farmers was conducted. Most farmers in Ethiopia and Kenya had knowledge about fall armyworm; they could identify it mainly during its larval stage. Furthermore, most farmers in Ethiopia (93%) and Kenya (97%) encountered damage by fall armyworm in their farms. They estimated an average of 32% crop damage in Ethiopia and 47.3% of crop damage in Kenya, with an estimated yield reduction between 0.8 to 1 tonnes/ha. Nearly half of the farmers relied on chemical insecticides to control this pest. The majority (60%) of the farmers in Kenya perceived that insecticides were not effective in controlling fall armyworm as compared to most farmers (46%) in Ethiopia who perceived that chemical spray is effective for the control of fall armyworm. In Ethiopia, 26% of the farmers combined handpicking larvae with insecticide sprays, whilst 15% of the farmers practiced only handpicking. The present study highlights the need to develop management strategies for fall armyworm based on farmers’ needs and priorities.  相似文献   
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