Analysis of indigenous production methods and farm-based biodiversity of amochi (<Emphasis Type="Italic">Arisaema schimperianum</Emphasis> Schott) in two sub-zones of Southern Ethiopia

For the first time we report that diverse types of Arisaema schimperianum Schott locally called amochi, are grown and managed as an off-season food crop in Southern Ethiopia. Participatory Rural Appraisal (PRA) and formal survey studies on 204 households were conducted over two consecutive years (2003–2004) in Chencha and Dita sub zones of Southern Ethiopia, to identify indigenous production methods and farm based biodiversity of amochi. Amochi is propagated from seed tubers and tuber parts left in the soil from the preceding harvest and grow during the dry season, February to June. Average share of proportion in the annual household consumption from amochi tubers was 9% and 4% for Chencha and Dita respectively. Uncooked amochi is irritating in contact to skin and mouth. Fifteen amochi types were identified in Dita and 12 in Chencha. They differ in the level of irritation, maturity and yield. Rich farmers with large family size as a working force, large farm size to support larger number of livestock that is source of farmyard manure, have farms with larger diversity of amochi than their poor counterparts, suggesting that its diversity is influenced by house hold characteristics and favoured under relatively fertile soil conditions. In both sub zones women had better experience in identifying amochi types than men. Further study is needed to identify chemical contents; and genetic variation using morphologic and molecular traits, in order to develop a strategy to assess and utilise the existing genetic diversity.     

Evaluation of trypanosomiasis control alternatives using an epidemiologic simulation model

The effect of various disease-vector control alternatives on the prevalence of trypanosomiasis in southwest Ethiopia was examined with the aid of an epidemiologic model. The alternatives considered included vegetation clearing by manual labor, game elimination, insecticidal spraying from airplanes coupled with settlement, use of sterile male Glossina, avoidance of tsetse infested areas, increasing the resistance of the cattle population, therapy, and combinations of the above methods. First, the currently estimated endemic prevalence of trypanosomiasis (27.3%) in the simulated area of Ethiopia was established and maintained over a 10 year period. Then, various control alternatives were introduced and the simulation was run for an additional 10 years to observe the effect of these control alternatives on the prevalence. The combined use of vegetation clearing, insecticides, therapy, and settlement (or resettlement) was the most effective and feasible method of trypanosomiasis control for the simulated situation.     

Effects of variety, cropping year, location and fertilizer application on nutritive value of durum wheat straw

This study was carried out to assess the effects of variety, year, location and level of fertilizer application on chemical composition and in sacco dry matter (DM) degradability of durum wheat straw as well as to understand the relationship between straw quality and agronomic traits of the crop and to assess the possibilities of selecting wheat varieties that combine high grain yield with desirable straw quality. Two local (Arendeto and Tikur sinde) and two improved (Boohai and Gerardo) varieties of durum wheat (Triticum turgidum Desf.) were used in the experiment. The four varieties were grown at two locations (Akaki and Ejere) in the years 2001/2002 and 2002/2003 in 5 x 5 m plots in three replications. Diammonium phosphate and urea fertilizers were applied at four levels (0/0, 32/23, 41/23 and 64/46 kg/ha of nitrogen/phosphorus). Straw quality was assessed based on chemical composition and in sacco DM degradability. Correlation of straw quality with grain and straw yield and with other agronomic characteristics of the crop was determined. The potential utility index (a measure that integrates grain and digestible straw yield) was used for ranking of the varieties. The local varieties had higher crude protein (CP) and lower neutral detergent fibre contents and higher digestibility than the improved varieties. The cropping year and location had significant effect on CP content and degradability of the straw, which could be due to climatic variation. However, the fertilizer level did not have any significant effect on straw quality except that the CP content of the straw tended to increase with increasing level of fertilizer application. Based on the potential utility index the varieties ranked, in a decreasing order, as Tikur sinde > Arendeto > Gerardo > Boohai and the ranking was consistent across years and locations. Except the CP content, straw quality was not negatively correlated with grain and straw yield. This indicates that there is a possibility of selecting varieties of wheat that combine high grain and straw yield with desirable straw quality.     

Risk factors for bovine mastitis with the isolation and identification of Streptococcus agalactiae from farms in and around Haramaya district,eastern Ethiopia

Tropical Animal Health and Production - A cross-sectional study was carried out to determine the prevalence and risk factors of bovine mastitis caused by Streptococcus agalactiae from farms in and...     

Analysis of korarima (<Emphasis Type="Italic">Aframomum corrorima</Emphasis> (Braun) P.C.M. Jansen) indigenous production practices and farm based biodiversity in southern Ethiopia

Korarima (Aframomum corrorima (Braun) P.C.M. Jansen) production is declining mainly due to destruction of the plant’s natural habitat. A survey was conducted in the three major korarima growing administrative zones, Gamo Gofa, Debub Omo and Kaffa in southern Ethiopia to assess indigenous production practices, wealth status, farm based biodiversity and household characteristics using participatory rural appraisal (PRA) and semi-structured questionnaires. The wealth is unevenly distributed among households and not significantly different for korarima growers and non-korarima growers. Farmers acknowledged that shortage of shade trees; low yield and lack of improved varieties had contributed to decrease in production area (PA). A total of three distinct named korarima landraces were recorded, with a range from one to three on individual farms implying low farm based biodiversity. More households grew enset (Ensete ventricosum (Welw.) Cheesman) in Gamo Gofa and Kaffa while maize (Zea mays L.) was grown by nearly all households in Debub Omo. Only a few households grew korarima. Most of the household characteristics significantly affected the PA of korarima. The correlation coefficients indicated that the relationship of household characteristics were significant. Findings of this study suggest that the maintenance of shade trees on the main farm field is the main requirement for korarima production.     

Livestock Browsing,Not Water Limitations,Contributes to Recruitment Failure of Dobera glabra in Semiarid Ethiopia

The study used nursery and field experiments to investigate why recruitment of Dobera glabra (Forssk) Poir., a native food source for both humans and livestock, often fails in the semiarid rangelands of Afar, Ethiopia. We hypothesized that soil water limitations and browsing by livestock would be the primary mechanisms accounting for the failure of natural regeneration. We used three sets of experiments—1) seedling performance in response to shade and watering in a nursery, 2) field regeneration with and without browsing, and 3) regeneration beneath trees with and without browsing—to examine regeneration success. Seedlings were established in plots from seeds sown directly into the soil for nursery and field experiments, but natural germination occurred beneath trees. Survival and relative growth rates (RGR) were used to monitor seedling performance. Seedlings that received neither shade nor watering treatments had lower seedling survival (53 ± 15%) as compared with other treatment combinations. Highest seedling survival was recorded under shade and 1 d watering s wk^-1 treatment combinations (92 ± 1%). However, shade treatments had a minimal increase on seedling RGR. Water limitation is not a crucial limiting factor for D. glabra recruitment, as 53% of the seedlings survived without both shade and supplemental water for 1 yr. Field experiments, however, demonstrated that browsing greatly reduced seedling survival (below 15%) and suppressed growth of surviving seedlings, suggesting that browsing is the major factor preventing natural recruitment. Natural recruitment of D. glabra is unlikely with the existing continuous and intensive grazing/browsing in Afar rangelands, where the mobility of pastoralists is restricted. We suggest that planting nursery-raised seedlings in home gardens of settled pastoralists and establishment of grazing reserves in some key range sites that contain D. glabra could help offset the recruitment failure of native food species D. glabra in Afar rangelands.     

Factors Affecting Small-Scale Farmers’ Land Allocation and Tree Density Decisions in an <Emphasis Type="Italic">Acacia decurrens</Emphasis>-Based <Emphasis Type="Italic">taungya</Emphasis> System in Fagita Lekoma District,North-Western Ethiopia

The development of woodlots as an additional source of livelihood and as a land management option for small-scale farmers is a challenging issue in the cereal-based subsistence farming systems of north-western Ethiopia. There is a need to understand why and which factors determine the decisions of small-scale farmers to grow short-rotation woodlots on their land. Data used in this study were collected from a survey of 200 randomly selected households in the region. A Tobit regression model was used to determine predictor variables for farmers’ decisions to allocate land to planting Acacia decurrens (J.C. Wendl.) Willd. and at what density trees are planted on the respective plots. The most important motivations for planting A. decurrens were income, soil fertility management, and soil and water conservation. Having a male head of household, long distance to markets and plots being on marginal land, among other factors, increased the allocation of land to A. decurrens woodlots. Having a male head of household, access to credit and plots being on marginal land, among other factors, increased tree planting density. Age had a negative effect on both allocation of land to woodlots and tree density, whereas farm size had an inverted U-shaped relationship with both decisions. These results suggest that wider expansion of A. decurrens-based plantation systems could be achieved through improving extension, credit access and road infrastructure to connect small-scale farmers to markets and finance.     

Seroprevalence and associated risk factors of bovine brucellosis in Addis Ababa dairy farms

A cross-sectional study was carried out on bovine brucellosis in Addis Ababa dairy farms from November 2003 to April 2004. A total of 1,202 blood samples were collected from non-vaccinated, cross-bred dairy cattle. The Rose Bengal plate test (RBPT) was used as a screening test. Those serum samples reacting positively to RBPT were subjected to the complement fixation test (CFT) for confirmation. The RBPT detected 30 of 1,202 (2.5%) of the samples as brucellosis positive. The positive sera when further retested using CFT, 18 out of the 30 RBPT positive sera were confirmed to be positive. The prevalence of brucellosis based on CFT in the study area was 1.5%, and all positive sera were from female cattle. Result of the questionnaire survey revealed that percentage of 4.4% abortion and 9.5% retained fetal membranes. Abortion and retained fetal membranes were associated with Brucella antibodies (P?相似文献