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11.
Bovine mastitis and its association with selected risk factors in smallholder dairy farms in and around Bahir Dar,Ethiopia 总被引:1,自引:1,他引:0
Three hundred fifty one (195 local zebu and 156 Holstein x local zebu crosses) lactating cows of smallholder farms in Bahir Dar 'milk shed' were examined from September 2003 to March 2004 to determine mastitis prevalence, isolate pathogens and identify the role of some potential risk factors. Clinical prevalence was determined through examination of abnormalities of milk, udder or cow. California mastitis test (CMT) was used for determination of subclinical mastitis prevalence. Clinical prevalence at cow level was 3.9% in crossbreds and none in local zebu breeds. Subclinical mastitis at cow level based on CMT was high (34.4%) in crossbreds compared to indigenous zebu (17.9%) (p < 0.05). Quarter subclinical prevalence based on CMT was 17.9% and 4.9% in crossbreds and local zebu, respectively. The pathogens isolated from mastitic milk (CMT positive milk) were coagulase negative staphylococci (CNS), S. aureus, Str. agalactiae, Str. dysgalactiae, Str. uberis, Micrococcus species, C. bovis, A. pyogens, B. cereus, and S. intermedius. Among these, the most frequent isolates were CNS (50%), S. aureus (19%), Str. agalactiae (8%) and Str. dysgalactiae (7%). Among potential risk factors considered, stage of lactation, parity and breed were found to affect the occurrence of mastitis significantly (p < 0.05). 相似文献
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Awegechew Teshome Daniel Patterson Zemede Asfaw Sarah Dalle J. Kenneth Torrance 《Genetic Resources and Crop Evolution》2016,63(1):55-77
Temporal and spatial changes in sorghum landrace diversity and distribution, field sizes, and farmers’ selection criteria were studied in five agricultural landscapes in North Shewa and South Wollo, Ethiopia. The study was undertaken during 2000/2001 and 2011/2012 cropping seasons in order to ascertain the stability of a range of factors that support the maintenance of sorghum landrace diversity. The same farmers were interviewed and the same sorghum fields were surveyed during both cropping seasons to determine the changes over the 11-year period. Farmers’ selection criteria increased significantly in all agricultural landscapes [Bati (P < 0.0001); Borkena (P < 0.0015); Epheson (P < 0.002); Hayk (P < 0.022); and Merewa Adere (P < 0.05)]. In Bati (P < 0.0081) and Merewa Adere (P < 0.0087), fields planted to sorghum landraces have increased significantly. Changes in field sizes in Epheson (P < 0.36) and Hayk (P < 0.237) did not show significant differences. The field sizes in Borkena (P < 0.0001) have decreased significantly due to population growth, land distribution policy, and seasonal variations followed by inter-and intra-species crop diversification. Sorghum landrace richness has increased significantly in Bati (P < 0.0001) and Hayk (P < 0.0001), marginally increased in Merewa Adere (P < 0.08). No significant changes have been observed in sorghum landrace richness in Borkena (P < 0.344) and Epheson (P < 0.24). In 2011/2012, 24 “generalist” sorghum landraces (grown widely across three or more agricultural landscapes), and 53 “specialist” sorghum landraces (restricted to certain microhabitats in one or two agricultural landscapes) were found. Landrace dynamics in response to farmers’ selection criteria and environmental variations are explained. 相似文献
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Agroforestry Systems - Conspicuous trees and other perennial plants in smallholders’ farms have been acknowledged for their biodiversity conservation values. Impacts of agroforestry... 相似文献
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The present study was conducted to assess the seroprevalence of peste des petits ruminants (PPR) in sheep and goats in Awash Fentale district, Afar, Ethiopia. Small ruminants in the district had poor herd immunity at the first visit and succumb to the disease then after. The seroprevalence during the time of an outbreak was much higher compared with the initial levels: 7.3% and 42.6% in sheep and goats, respectively. The higher seroprevalence figure in goats was suggestive of their relative susceptibility to PPR compared with sheep. 相似文献
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Although homegardens are most often suggested as the refuges for biodiversity in human-dominated landscapes, how the surrounding landscape and socioeconomic characteristics affect this diversity in the tropics has received little research attention. Hence, this study has examined how these factors affect woody species diversity in homegardens of northeast Ethiopia. Three landscapes which are similar in agroecology were selected and in total 54 households were used for both a survey and a woody species inventory in respondents’ homegardens. The homegardens were stratified based on their locations in relation to crop fields and natural vegetation using satellite images from Google Earth. The variation in Shannon–Wiener diversity index among homegardens and the effect of the socioeconomic factors including household wealth status, homegarden area and the households’ types of uses of woody plants on species diversity were analyzed using one-way ANOVA. Altogether 53 woody plant species belonging to 35 botanical families were identified. Survey results indicated that the woody species diversity was higher in homegardens situated close to crop land as compared with the diversity in homegardens close to natural vegetation. Higher woody species diversity was recorded in homegardens which are larger in area and where the households’ types of uses of woody plants is higher. Moreover, the woody species diversity was found to be higher in homegardens of the high and medium income households when compared with that of poor households. Overall, results suggest that the concurrent ecological and socioeconomic studies are needed to design conservation strategy and policy for plant biodiversity in agricultural landscapes. 相似文献
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Based on farmers’ knowledge and laboratory studies, the nutrient accumulation in the topsoil (0–20 cm) under Cordia africana Lam (Cordia), Millettia ferruginea Hochst (Millettia) and Eucalyptus camaldulensis Dehnhardt (Red gum) managed under two agroforestry practices on different farms at three sites was evaluated. The number
of these trees on individual farms has increased during the last two decades. The number of stems ha−1 of Red gum was higher on farms of wealthier households than on farms of poor and medium households at two of the sites, but,
at one site the number of stems ha−1 on farms of poor households was higher than on farms of wealthier households. Apart from the concentration of Na in the topsoil,
there were significant variations in the analysed soil nutrients between the tree species. At all study sites, significantly
higher concentration of P was observed under Millettia and Cordia than under Red gum. At one site, concentrations of available
P under Cordia were nearly two-fold, and four and half-fold greater than under Millettia and Red gum, respectively. At one
site, total N under Red gum was 14% and 24% lower than under Cordia and Millettia, respectively. In contrast, organic C content
under Red gum was 11.6% greater than under Millettia and 23.8% greater than under Cordia. The pH under Millettia and Cordia
were significantly higher than concentrations under Red gum at one site. Topsoil under Millettia and Cordia also had significantly higher levels of exchangeable Ca and Mg than Red gum. 相似文献
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We undertook ethnobotanical study of forage/fodder plant species used by the Afar and Oromo (Kereyu and lttu) Nations in and around the semi=arid Awash National Park (ANP), Ethiopia. The study aimed at investigating and documenting indigenous knowledge (IK) on forage/fodder plant species and threats to their survival. Ninety-six in= formants between 20 and 80 years old were selected using prior informa- tion. Data were collected using semi-structured interview, guided field wail discussion and field observation. Preference ranking, Jaccard's coefficient of similarity and priority ranking were used for data analysis. One hundred twenty-six forage/fodder species of 90 genera and 43 fami- lies were collected in the study area. More than 88% of the species were reported with their vernacular names, where 68% were reported by the Afar Nation and 70% by the Oromo Nation. Family Poaceae was repre- sented by 25 species (20%), followed by Fabaceae 18 (14%). Preference ranking for the most preferred forage grasses as perceived by key informants revealed that Chrysopogon plumulosus was the most important forage/fodder species. Overgrazing was the major threat in the study area, scoring 22%. 相似文献
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300 goat serum samples from an export-oriented abattoir were tested for contagious caprine pleuropneumonia antibodies by the
complement fixation test. The disease prevalence was 31% with no significant differences (P > 0.05) between the regions “Borena”,
“Bale”, “Afar” and “Jinka” or the age of the goats (P > 0.05). Gross pathology and histopathology of the lung primary lesions
were indicative of pleuropneumonia caused by Mycoplasma capricolum subsp. capripneumoniae. 相似文献
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Fufa Abunna Loma Asfaw Bekele Megersa Alemayehu Regassa 《Tropical animal health and production》2010,42(2):289-292
A study was carried out to determine the prevalence and the species of liver flukes in indigenous adult cattle, to compare the diagnostic efficiency of fecal and post mortem examination and to assess the economic significance of bovine fasciolosis due to liver condemnation in the abattoir. Of the 406 livers and fecal samples examined, 57 (14.0%) and 20 (4.9%) were positive for fasciolosis. The most common liver fluke species affecting the cattle was Fasciola gigantica, 9.1% of cattle were infected with F. gigantica while, Fasciola. hepatica, mixed infections and unidentified or immature forms of Fasciola spp. were present in 3.2 %, 0.7% and 1 % of cattle, respectively. A retrospective abattoir survey revealed that the prevalence of fasciolosis was 12.7%. The prevalence of fasciolosis recorded in this study was lower than that reported by other researchers in this country. There was a strong relationship between fecal examination and postmortem findings of liver lesions, (K?=?0.23) but under local conditions, postmortem examination was considered a better diagnostic tool for fasciolosis. Fasciolosis is of significant economic importance as the resultant liver condemnations caused an average loss of 4000 USD per annum. Hence, this disease deserves serious attention by the various stakeholders in order to promote the beef industry in the study area in particular and in the country in general. 相似文献