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1.
Land allocation has been an important issue in land use planning research studies. Land allocation involves different multifunctional activities of maximizing environmental, economic and social benefits. Multi-criteria decision making (MCDM) method is the most popular tool to optimize land allocation problems by considering decision variables, conflicting objectives, and criteria. Hence, decision-makers face problems on how to optimize the land allocation while minimizing the conflicting trade-offs existing in the decision analysis. With this review study, we aim at identifying and extracting information on MCDM methods to solve land allocation problems from English language articles published between 2000 and 2019 and indexed by four scientific literature databases (Web of Science, Science Direct, Scopus, Google scholar). To this end, we applied a systematic literature review approach, i.e. the Preferred Reporting Items for Systematic Reviews and Meta-Analysis procedure (Moher et al., 2009), with a structured database search expression. 120 articles were selected of which, after careful screening of title, keywords and abstract, 69 were retained for detailed review. This review study report compiles comprehensive information by classifying the papers into application area, optimization objectives, criteria used, decision techniques, publication year and study region. In summary, we found that in the last two decades, the use of the MCDM method has increased, particularly in Europe and China. AHP (analytical hierarchal process) is frequently used for multi-attribute land allocation problems with reference to ecotourism and ecosystem management. LP (linear programming) and SA (simulating annealing) methods are predominantly used to optimize multi-objectives complex agricultural and forest land allocation problems respectively.  相似文献   
2.
Summary Up to 100 single plant derived lines of 18 Ethiopian barley landraces were evaluated for infection type in the seedling and adult plant stage, and for latent period in the adult plant stage only. A low infection type indicates the presence of race-specific resistance genes of the hypersensitive type, while the latent period is the major component of the polygenic, partial resistance.In the seedling stage 1721 of these single plant derived landrace lines were assessed for infection type against two barley leaf rust races. In the adult plant stage 1227 from these 1721 lines were evaluated for infection type against one race. In the seedling stage 2 (against race 1-2-1) and 29 against race A) out of the 1721 lines showed an infection type lower than 6–7 on the 0 to 9 scale. In the adult plant stage none of the 1227 lines had an infection type lower than 6–7 against race 1-2-1.The variation between and within the landraces for latent period in the adult plant stage was large. Some landraces such as landrace 212845 showed a highly significant and longer mean latent period than most other landraces. Virtually all plants in all landraces carry at least some partial resistance.The near-absence of race-specific, major, resistance genes and the high frequency of moderate levels of partial resistance indicates that the durability of leaf rust resistance in Ethiopian barley landraces is due to the latter type of resistance, and that the multiline principle does not operate.  相似文献   
3.
The study was conducted in eight districts of Ethiopia with the objectives of determining the seroprevalence and associated risk factors of infectious bursal disease (IBD). From the total of 2,597 chicken serum samples examined using ELISA, 83.1 % were found positive. The highest seroprevalence was found at Mekele (90.3 %) while the lowest was recorded at Gondar district (69.8 %). These differences among the study areas were statistically significant (p?<?0.05). Highest seroprevalence was found in crossbreed of chicken (91.4 %) while the lowest was recorded in indigenous breed of chicken (81.4 %). This difference was statistically significant (p?<?0.05) among the three breeds of chickens, but sex was not statistically significant (p?>?0.05). The seroprevalence of the disease was found high in young (≤8 weeks) age group (86.6 %) while the lowest prevalence was recorded in adults (>8 weeks) (72 %). This is also statistically significant (p?<?0.05) between young and adult age groups. The prevalence of IBD in different production system indicated that higher seroprevalence was recorded in intensive production system (85.9 %) while the lowest was recorded in extensive production system (81.6 %). This difference is also statistically significant (p?<?0.05).  相似文献   
4.
Collective action, on communal grazing land, has evolved in the highlands of northwestern Ethiopia to mitigate the problems of feed shortage and land degradation due to overgrazing. The exercise is liked by farmers for improving the availability of natural pasture during the long dry season when other feed sources get depleted. However, large portions of the communal grazing lands are still managed under free grazing throughout the year. This study was undertaken in Maynet village in the upper Blue Nile basin, northwestern Ethiopia, to assess the impacts of three different types of grazing land management (GLM) and two slope gradients (<10%; 15–25%) on aboveground herbaceous biomass yield, ground cover, species richness, runoff, soil loss and soil bulk density of grazing lands. The GLMs include (a) freely open communal GLM, (b) restricted communal GLM – collective management of communal grazing land locally named as ‘yebere sar’ and (c) private holding GLM. Stocking density was more than carrying capacity of grazing lands across all GLMs. However, the extent of overstocking problem was exceptionally severe in freely open communal GLM. The interaction between GLM and slope was significant (P<0.05) for runoff, soil loss and runoff coefficient. The average runoff coefficient was close to 50% in freely open communal GLM on steeper slopes (15–25%). Freely open communal GLM on steeper slopes resulted in consistently highest cumulative runoff and soil loss amounting to 491 mm and 32 t/ha per year, respectively. Polynomial regression analysis showed that quadratic relationship (r2=0.87) existed between soil loss and runoff. But, soil loss was close to nil when runoff did not exceed 2 mm per rainfall event. As expected, restricted communal GLM appeared to reduce surface runoff by more than 40% and curb the rate of soil erosion by more than 50% compared to freely open communal GLM. Its vegetation cover persisted above 70% throughout the year, meeting the threshold level recommended to keep surface runoff and soil loss to minimum. Reducing the problem of overstocking and pasture resting in August–November are important components to improve ground cover and aboveground herbaceous biomass yield, which in turn reduce land degradation on grazing lands.  相似文献   
5.
The aim of the present study was to investigate the performances of camels kept by pastoralists with different degrees of experience in camel production. The study was conducted on 60 selected camel herds twice a year; during wet and dry seasons of 2003 and 2004 in Borana, Southern Ethiopia. The average ages at first parturition and calving intervals of breeding females were 68.1 ± 0.5 and 25.5 ± 0.4 months (LSMean ± SE), respectively. Age at first parturition was significantly reduced by use of veterinary services, while variation was not observed among Borana, Guji, Gabra and Somali herds. Calving intervals were significantly shorter (P < 0.05) in Borana (24.8 ± 0.6) and Guji (24.5 ± 1.5) than Somali herds (27.0 ± 0.5). Calving intervals were also prolonged (P < 0.05) by fixing breeding time. Annual calving, abortion and calf mortality rates were similar for the four populations and averaged 37.3%, 9.3%, 20.3% in 2003, and 41.3%, 8.2%, 14.9% in 2004, respectively. The overall mortality rate was significantly higher (P < 0.05) in Borana (10.0 ± 2.1) than in Gabra herds (4.2 ± 0.8). However, mortality was not statistically different for use of veterinary services and other managemental practices. The study showed an increase in annual herd growth by 5.7% in 2003 and 11.6% in 2004 with similarity of herd dynamics between the two years. Daily milk yield differed significantly (P < 0.05) depending on veterinary services, watering frequency and the season (7.6 L during wet and 4.3 L during dry season). Similarly, milk yield was significantly higher (P < 0.01) in Somali herds than in Borana and Gabra herds. In conclusion, the study revealed that some production and reproduction performances in camel herds have showed significant variation with varying levels of herding experience and veterinary services. This may suggest performance in pastoral camels can be enhanced with learning more about and using traditional management practices as well as improving animal health service delivery.  相似文献   
6.
Tropical Animal Health and Production -  相似文献   
7.
A cross-sectional study was conducted in Hawassa town and its surroundings from October 2007 to May 2008 to estimate the prevalence of bovine tuberculosis (BTB) based on comparative interadermal tuberculin test (CIDT) and abattoir survey. Accordingly, 39 herds comprising 413 cattle were subjected to CIDT, and the herd and individual animal prevalence were 48.7% (19/39) and 11.6% (48/413), respectively. One of the 16 milk samples collected from tuberculin-positive cows was culture positive. The prevalence significantly differed among the age group (P = 0.001) and management system (P = 0.001). Thus, age group over four (OR = 7.9) and animal with poor management system (OR = 4.1) had a higher odds for tuberculin reactivity compared to those with age group under four and cattle with good management system, respectively. Of the total 1,023 cattle subjected to postmortem examination, 11 (1.1%) were found to be positive for gross tuberculous lesions. Larger proportion (50%) of TB lesion was recorded in the respiratory pathway followed by digestive system (28.6%) and prescapular lymph nodes (21.4%). Of 14 tissue specimens collected from the gross lesions, four (28.6%) were positive for histopathological TB lesions. In conclusion, this study revealed the importance of BTB in the study area in particular and the region in general.  相似文献   
8.
The involvement of Brucella infection in causing abortion was investigated in a breeding female subpopulation of 283 cattle, 756 camels, and 757 goats. Serum samples were serially tested using the Rose Bengal test and complement fixation test. The study showed that anti-Brucella antibodies were prevalent in 10.6% (95% confidence interval (CI), 7.4, 14.9), 2.2% (95%CI, 1.4, 3.7), and 1.9% (95%CI, 1.1, 3.2) of cattle, camel, and goats, respectively. Abortion was more commonly reported in camels (23.4%) than cattle (13.8%) and goats (12.4%). The results of this study suggested that Brucella infections contribute significantly to abortion in cattle (odds ratio (OR), = 4.7; 95%CI, 2.0, 10.8) and goats (OR = 6.9; 95%CI, 2.2, 21.7) but not in camels. The number of young animals produced by breeding females seems to be apparently reduced in seropositive groups. Keeping more than two animal species at household level was found to be the risk factor for cattle (OR = 3.1; 95%CI, 1.2, 7.9) and camel (OR = 5.3; 95%CI, 1.2–23.5) seropositivity to Brucella infection when compared to those animals from households that keep only two animal species. This may suggest a possibility of cross species transmission of Brucella infection under such mixed herding. Wet season (OR = 4.8; 95%CI, 1.3, 18.1) was found to be associated with seropositivity in goats, linked to a coincidence of increased deliveries in flocks with possible excretion of Brucella organisms. The study results suggest that Brucella infection is the likely cause of abortion in cattle and goats while other causes largely outweigh brucellosis as a cause of abortion in camels in Borana, hence, contributing to reproductive loss.  相似文献   
9.
Surveys were undertaken in six districts of southwestern Ethiopia from July to October 2003 to investigate farmers’ perceptions and management practices of insect pests on traditionally stored sorghum. The survey involved 138 randomly selected farmers who were interviewed using a semi-structured questionnaire. Storage insect pests were perceived as the major insect pests of sorghum. The majority of the farmers estimated sorghum yield losses of up to 50% due to insect damage during storage. High temperature and lack of storage hygiene were cited as the major factors resulting in insect infestation of stored sorghum. Infestations of stored sorghum insect pests were common on different forms of sorghum, which stored in various types of farm storage. Farmers classified sorghum varieties according to the level of resistance to stored sorghum insect pests. Only about 32% of the farmers had access to chemical insecticides for the control of stored sorghum insect pests, while the majority of them used cultural practices and locally available plant materials as storage protectants.  相似文献   
10.

Equine reproduction is unique by having long behavioral estrus and differences in time of breeding between breeds and individuals of mares. An experimental study was conducted at the Balderas Sport Horses and Recreational Center, Addis Ababa, Ethiopia, from January to June, 2018, to evaluate conception rate to frozen semen in local and exotic crossbreed mares. Mares were teased to characterize estrus behavior and examined by ultrasound in determining imminent ovulation. Inseminations were done post ovulation within an average of 6–9 h using frozen-thawed semen. The overall conception rate to frozen semen was 15/21 (71.43%) with 8/11 (72.73%) in crossbreed and 7/10 (70%) in local breed mares. Age and body condition score (BCS) of animals had no significant effect on conception rate to AI with frozen semen. A slightly higher conception rate was obtained when ovulation was from the right ovary than when ovulated from the left ovary. A higher conception rate was obtained when the diameter of the preovulatory follicle was ≤ 45 mm than above diameter. The conception rate increased significantly with increased number of services/conception with an overall mean ± (SEM) of 2.2 ± 0.2 services/conception. A more number of services/conception were required for local breed (2.7 ± 0.2) than crossbreed mares (1.8 ± 0.3) and again for lower body condition scores than higher condition scores of mares. In conclusion, the increased number of services improved the conception rate with significant difference between breed of mares, whereas good management of mares for improved body conditions could be required to decrease the number of services per conception.

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