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41.
A cross sectional study was undertaken from October 2010 to March 2011 to determine the seroprevalence of contagious bovine pleuropneumonia (CBPP) and its related risk factors in export quarantine centers. A total of 3,111 cattle sera were collected from different export quarantine farms located in and around Adama, namely, Bekero, Jogo, Kedir, and Dera farms, and tested for the presence of Mycoplasma mycoides subsp. mycoides small colonies antibody using competitive enzyme-linked immunosorbant assay. Of the total 3,111 cattle sera examined, 124 (4 %) were found positive for CBPP. Among the potential predisposing factors assessed, origin, transportation condition, confinement level, and stay time of the animals in quarantine center were not found significantly (P?>?0.05) associated with the occurrence of the disease. Whereas age was found significantly (P?<?0.05) associated with the occurrence of the disease in which a high seroprevalence was recorded in aged (9.5 %) animals than young (3 %). Generally, this study showed that CBPP is a threat for Ethiopian livestock export market and a well established disease in Borana and Bale areas, where the animals originated.  相似文献   
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The faba bean is among the major grain legumes cultivated in Ethiopia and is used extensively as a break crop in the highlands. Although a blanket application of DAP (diammonium phosphate) at the rate of 100 kg · ha?1 has been practised in faba bean production in the country, this was not based on research results. In addition, little information is available on the response of the crop to N and P fertilizers under diverse environmental conditions. Hence, field experiments were carried out at three locations in 1991, seven locations during 1992 and 1993 and at one location in both 1993 and 1995 to determine faba bean response to N and P fertilization. Five levels of N (0, 9, 18, 27 and 36 kg N · ha?1 as urea) in factorial combinations with four levels of P (0, 23, 46 and 69 kg P2O5 · ha?1 as TSP [triple super phosphate]) were studied in a randomized complete block design with four replications in the first year. In the remaining years four levels of N (0, 18, 27 and 36 kg N · ha?1 as urea) in factorial combinations with four levels of P (0, 23, 46 and 92 kg P2O5 · ha?1 as TSP) were used in a randomized complete block design with three and four replications at one and seven locations, respectively. Results indicated that a positive linear response of faba bean seed yield was noted at all locations (except Debre Zeit and Burkitu) to P fertilization, while a significant quadratic response was also found at Holetta. In addition, plant height, above ground biomass and number of pods per plant were positively influenced by P application while the effect of N on these was mostly nonsignificant. Faba bean seed yield response to N was noted at only two out of eight locations; in most cases, nonsignificant and inconsistent seed yield responses to N fertilization were obtained. There was nonsignificant N × P rate interaction. In conclusion, we do not recommend supplemental N application to faba bean at six out of eight locations but we recommend the application of P fertilizer to faba bean at almost all locations (with the exception of Debre Zeit) and for other soils deficient in available P. Further work is recommended on the determination of critical levels for soil-available P, below which P fertilization should be practised for optimum faba bean seed yield.  相似文献   
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A cross-sectional investigation was made into the seroprevalence of brucellosis in camels in three arid and semi-arid camel-rearing regions of Ethiopia (Afar, Somali and Borena) between November 2000 and April 2001. When sera collected from 1442 accessible camels were screened with the Rose Bengal plate test (RBPT), 82 (5.7%) of them reacted. The results of a complement fixation test (CFT) on those sera that had given a positive reaction to the screening test then indicated a 4.2% prevalence of brucellosis in the tested camels. There was a significant difference in the prevalence of brucellosis (2 = 7.91, p<0.05), which was highest in Afar (5.2%) followed by Somali (2.8%) and Borena (1.2%) regions. Camels in Afar had a four times higher risk of brucellosis with an odds ratio (OR) of 4.34 (confidence interval, CI = 1.76–10.72, p<0.001) compared to the risk in Borena. Likewise, Afar had higher risk (OR = 1.76, 1.13–2.74, p<0.05) than that in Somali. There was no significant difference in seroprevalence between the sexes (p>0.05). Although a higher prevalence (6.3%) was observed in camels over 3 years old in Afar, there was no significant overall age difference (p>0.05).  相似文献   
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Walleye dermal sarcoma virus (WDSV) is a type of retrovirus, which affects most of the adult walleye fishes during the spawning time. The virus causes multiple epithelial tumors on the fish’s skin and fins that are liable for more than 50% of the mortality rate of fish around the world. Till now, no effective antiviral drug or vaccine candidates have been developed that can block the progression of the disease caused by the pathogen. It was found that the 582-amino-acid (aa) residues long internal structural gag polyprotein of the virus plays an important role in virus budding and virion maturation outside of the cell. Inhibition of the protein can block the budding and virion maturation process and can be developed as an antiviral drug candidate against the virus. Therefore, the study aimed to identify potential natural antiviral drug candidates from the tropical mangrove marine plant Avicennia alba, which will be able to block the budding and virion maturation process by inhibiting the activity of the gag protein of the virus. Initially, a homology modeling approach was applied to identify the 3D structure, followed by refinement and validation of the protein. The refined protein structures were then utilized for molecular docking simulation. Eleven phytochemical compounds have been isolated from the marine plant and docked against the virus gag polyprotein. Three compounds, namely Friedlein (CID244297), Phytosterols (CID12303662), and 1-Triacontanol (CID68972) have been selected based on their docking score −8.5 kcal/mol, −8.0 kcal/mol and −7.9 kcal/mol, respectively, and were evaluated through ADME (Absorption, Distribution, Metabolism and Excretion), and toxicity properties. Finally, molecular dynamics (MD) simulation was applied to confirm the binding stability of the protein-ligands complex structure. The ADME and toxicity analysis reveal the efficacy and non-toxic properties of the compounds, where MD simulation confirmed the binding stability of the selected three compounds with the targeted protein. This computational study revealed the virtuous value of the selected three compounds against the targeted gag polyprotein and will be effective and promising antiviral candidates against the pathogen in a significant and worthwhile manner. Although in vitro and in vivo study is required for further evaluation of the compounds against the targeted protein.  相似文献   
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The present study was undertaken to determine the prevalence and distribution of Salmonella from apparently healthy slaughtered camels in Eastern Ethiopia. A total of 714 samples (faeces, mesenteric, lymph nodes, spleen, liver, abdominal and diaphragmatic muscles) from 119 slaughtered camels were analysed. Salmonellae were detected from 116 (16.2%) of the 714 samples examined. Eighteen (15.1%) faeces, 19 (15.9%) mesenteric lymph nodes, 14 (11.8%) livers and 17 (14.3%) spleen samples (n = 119 for each) were positive for Salmonella. Salmonellae were found in 20.1% of the abdominal and diaphragmatic muscles. A total of sixteen different serotypes were identified of which Salmonella saintpaul (38.8%) and S. braenderup (22.4%) were the most prevalent followed by S. muenchen (8.6%), S. kottbus (6.0%) and S. havana (5.2%). Other serotypes, including S. typhimurium, S. heidelberg and S. enteritidis were also detected from Ethiopian camels.  相似文献   
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