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71.
Bekele ST 《Tropical animal health and production》2008,40(1):25-28
Camels are important animals for pastoralists in the northeastern, eastern, southeastern and southern parts of Ethiopia. This
paper reports on abattoir study of respiratory lesions in 104 adult camels at the Dire Dawa abattoir (88 male and 16 female).
The study showed 98% of the examined lungs had one or more lesions. The most common lesions were pulmonary fibrosis (50.00%),
pneumoconiosis (34.62%), hydatid cyst (30.80%), pulmonary abscess (3.85%) and parasitic bronchopneumonia (0.96%). The distribution
of pneumoconiosis and hydatid cyst varied significantly (p < 0.05) among different lobes, the highest being seen in the caudal
lobe. For the different lesions there was no significant (p > 0.05) difference in distribution among male and female camels.
Possible explanations for the occurrence of the lesions are discussed. And recommendations forecasted are made. 相似文献
72.
The performance of indirect fluorescence antibody test (IFAT) for serological diagnosis and screening of lumpy skin disease (LSD) was evaluated using methods without gold standard. Virus neutralization test (VNT) was used as the second test and the study sites were selected from two different geographical places in Ethiopia to get different disease prevalence. The analysis of conditional dependent Bayesian model for the accuracy of IFAT showed that sensitivity, specificity, prevalence of the population Pi1 and the population Pi2 were 0.92 (0.89–0.95), 0.88 (0.85–0.91), 0.28 (0.25–0.32) and 0.06 (0.048–0.075), respectively. The posterior inferences obtained for VNT sensitivity, specificity and conditional correlation between the tests for sensitivity (rhoD) and specificity (rhoDc) were 0.78 (0.74–0.83), 0.97 (0.95–0.99), 0.052 (−0.03–0.15) and 0.019 (−0.01–0.06), respectively. The interval estimation of conditional correlation for both sensitivity and specificity clusters around zero and thus conditional dependence between the two tests was not significant. Although accuracy measure would not be the only basis for test selection, the result of our study demonstrated that IFAT has a reasonable high accuracy to be used for the diagnosis and sero-surveillance analysis of LSD in the target population. 相似文献
73.
Tefera M 《Tropical animal health and production》2004,36(2):105-116
This study reports evidence of animal exploitation during the Axumite era based on a survey of architectural features, rock art and artefacts recovered from the archaeological site at Axum, northern Ethiopia. Animals and agricultural tools were identified from materials not previously examined. Pottery, rock art and animal remains revealed a range of zoological species. Agricultural implements and sacrificial vessels also provided indirect evidence of animal exploitation. It is concluded that, in addition to plough-based agriculture, the hunting of large wild animals, such as elephants and lions, and the exploitation of domestic cattle, small ruminants and poultry were part of the Axumite subsistence regime. Although it is difficult to reconstruct an overall subsistence pattern based on this study alone, the physical and biological evidence suggests that the Axumites practised combined cultivation and animal herding. Further investigation is required to study the types and breeds of animals and their distribution in time and space. 相似文献
74.
An investigation was made into coccidiosis of 190 scavenging indigenous chickens between September 2000 and April 2001 in three selected agroclimatic zones, in central Ethiopia. This was done through clinical, postmortem and microscopic examinations. Data were processed by chi-square and Mantel-Haenzel test. The study indicated that 25.8% (49/190) of the chickens were infected with coccidiosis and found to harbour one to four different species of Eimeria. Of these infected chickens, 30 (15.8%) and 19 (10.0%) were positive for clinical and sub-clinical coccidiosis, respectively. There was a significant altitude difference (chi2 = 14.7, p <0.001) in coccidiosis prevalence: 42.2% in chickens from highland region followed by 21.5% in mid-altitude and 13.1% in low-altitude areas. When quantified, the prevalence of coccidiosis was 2.66 and 4.83 times higher in the high-altitude than in mid-altitude (odds ratio, OR = 2.66, p<0.05) and low-altitude (OR = 4.83, p<0.001) chickens. The pathogenic Eimeria species responsible for clinical coccidiosis were E. necatrix, E. acervulina, E. maxima and E. tenella. With increasing demand for poultry products in developing countries, knowledge of production constraints in traditional management practices could help devise control strategies for constraints on backyard poultry production systems. 相似文献
75.
Stone bunding ( kab ) is an age‐old local conservation practice at Mesobit‐Gedeba. This study was conducted to assess the effect of this indigenous practice on crop yield. We compared original ground slope, terrace width, and slope position of the terraced area. The effect of slope width and slope position were found significant (p < 0·05) for both grain and biomass yields of the terraced sites. The mean grain and biomass yields decreased as the original ground slope of the terraced site increased. Both grain and biomass yields decreased with the width of the inter‐terrace area. Significant differences (p < 0·05) in mean grain and biomass yields were observed between the three slope positions. They decreased as one moved up the slope within the inter‐terrace area. In general, the study indicated that indigenous stone bunding has a positive effect on sorghum yield. Future studies should address different locations and crops and ways of integrating indigenous stone bunding with the current conservation programmes of the region. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
76.
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
77.
The study was conducted in East Shewa, central Ethiopia, where durum wheat landraces were once popular, but were displaced
and re-introduced. Combinations of survey techniques are employed to document the different home uses of durum wheat landraces
and to assess whether these serve as an incentive to on-farm conservation. The findings reveal that wheat landraces have multiple
dietary and sociocultural uses that contribute to the maintenance of landraces on-farm. Temporal analysis of historical information
showed that (1) richness in food traditions is associated with a high level of landrace diversity on-farm; (2) food traditions
in East Shewa did not change radically as a result of the integration of farmers into the market economy; and (3) farm households
still have an appreciation of, and a preference for, the home-use related qualities of the landraces, this despite their long
term disappearance and the subsequent availability of several improved wheat varieties. The study illustrates the relationship
between the local availability of landrace wheats and their on-farm survival. The home uses of landraces plays an instrumental
role in the promotion of on-farm (in situ) conservation. Augmenting conservation activities with non-breeding approaches (e.g., awareness-creation) would support the
survival of wheat landraces for the foreseeable future.
Bayush
Tsegaye
(PhD) is a graduate from Noragric – the Department of International Environment and Development Studies, of the Norwegian
University of Life Sciences. Prior to joining the University, she was engaged in various development programs in Ethiopia
affiliated with government institutions as well as national and international non-governmental organizations. Her research
interests include community management of plant genetic resources, food security, and gender issues.
Trygve Berg
is an Associate Professor at Noragric – the Department of International Environment and Development Studies, of the Norwegian
University of Life Sciences. His research interests focus on the management of plant genetic resources and participatory plant
breeding. 相似文献
78.
79.
In the discussion on targeting of development interventions there is an ongoing debate on the usefulness of geographic targeting versus targeting of specific household types. In this paper, we examine the degree to which there is heterogeneity in the diversity of livelihood strategies in comparable geographic areas in northern Ethiopia. We use the concept of development domains to quantify differences amongst specific geographic areas (communities) and estimate the degree to which development domain dimensions account for differences in production systems indicators and to what extent variability between the overall results and the observed patterns can be attributed to these development domain dimensions. Our research shows that development domain dimensions matter both for production indicators (choice of technology, investment, cropping pattern and livestock use), as well as for the occurrence of heterogeneity in those indicators. Diversity is especially linked to better market access, homogeneity in agricultural production indicators to poor soils. This offers scope for targeting development interventions. 相似文献
80.
The effectiveness of loose rock check dams for gully control in Tigray, northern Ethiopia 总被引:5,自引:0,他引:5
J. Nyssen M. Veyret-Picot J. Poesen J. Moeyersons Mitiku Haile J. Deckers G. Govers 《Soil Use and Management》2004,20(1):55-64
Abstract. Over the last two decades, large gully control programmes have been established in Ethiopia. Based on detailed observations and measurements of 400 check dams in the highlands near Hagere Selam (Tigray, northern Ethiopian Highlands), the effectiveness of the check dam technique was assessed. In this study, catchment area, slope gradient, technical characteristics and the presence of smectite clays are the main factors controlling dam stability. Simple and logistic regression techniques were used to analyse the data. The frequent collapse of dams (39% after two years) is strongly associated with drainage area ( A ) and slope gradient of the soil surface near the gully ( S ), the product of these factors ( S × A ) being a proxy for runoff energy. Good functioning dams have a spillway, apron, concave plan form (when looking downslope) and are built at vertical intervals and with heights that result in a negative slope gradient of the line connecting the spillway and the foot of the upstream dam. Therefore, a reverse slope of this line is recommended. Furthermore, if large cracks are present in smectite-rich soils, the construction of check dams can lead to piping and concentrated flow bypassing the dam. Given that the collapse of some check dams seems inevitable where catchment areas are large or there are steep slopes, it is necessary to repair dams as soon as partial collapse starts and to complement this gully control technique with biological control measures. 相似文献