47 research outputs found

    Study on the prevalence of ectoparasite infestation of ruminanats in and around Kombolcha and damage to fresh goat pelts and wet blue (pickled) skin at Kombolch Tannary, Northestern Ethiopia

    Get PDF
    An attempt was made to study the prevalence of ectoparasite damage on live cattle, sheep and goats in and around Kombolcha town and on raw goat skin to assess their skin defect on processed wet-blue (pickled) skins at Kombolcha tannery, south wollo zone, North-Eastern Ethiopia. A total of 240 cattle, 175 sheep, 66 goats, were used to study the prevalence of ectoprasites on live animals as well as 344 fresh goat pelts and pickled (wet-blue) goat skins were used to assess skin defects. The result obtained from live cattle demonstrated a high prevalence of Amblyomma (28.33%) followed by Sarcoptes scabiei (23.75%), Boophilus (11.25%) Demodex (9.58%), Psoroptes (0.4 %), respevtively. The prevalence of ectoprasite infestation of live sheep revealed Mellophagus ovinus (sheep ked) (32.57%), Bovicola ovis (22.28%), Amblyomma spp (12.57%), Sarcoptes scabiei (14.28 %), Ctenocephaliedes spp (8.57%), Demodex (6.85%), Linognathus africanus (6.28%) and Boophilus spp (4%). The result from goats demonstrates a high prevalence of Sarcoptes scabiei (30.3%) followed by Linognathus stenopsis (9.09%), Amblyomma (4.54%), Ctenocephalides spp (3.03%), Bovicola caprea (1.51%) and Demodex (1.51%) in that order. Result obtained from fresh goats pelts revealed an over all high prevalence of Sacoptes scabie (53.29%) followed by Linognathus stenopsis (9.88%), Bovicola caprae (2.08%) and Demodex (2.08%). Examination of pickled (wet-blue) skins from follow-up skins show a high prevalence of scratch (74.25%) followed by “Ekek” (68.56%), scar (67.06%), processing defect (28.44%). “Ekek” (Typical scatter type cockle) was found to show a significant (

    Correlation and path coefficient analyses of cowpea (Vigna unguiculata L.) landraces in Ethiopia

    Get PDF
    Open Access Journal; Published online: 29 Dec 2018Understanding the nature and extent of association between yield and yield related traits is the prerequisite study for any underutilized crop improvements of sustainable genetic enhancement. However, there is a lack of sufficient information on seed yield and related trait correlation and path coefficient analysis of cowpea in Ethiopia. To fill the existing knowledge gap, the present study was conducted to determine the nature and extent of phenotypic and genotypic correlation and path coefficient analysis among 18 quantitative traits. A total of 324 cowpea landraces were tested in 18 Ă— 18 simple lattice design at Melkassa Agricultural Research Center and Miesso sub center during 2016 cropping season. The magnitude of genotypic correlations was higher than phenotypic correlations in most traits at both locations; this implies that the traits under consideration were genetically controlled. Seed yield was positively and highly significantly correlated with most of the traits at phenotypic and genotypic levels, indicating the presence of strong inherited association between seed yield and the other 17 traits. Almost all traits genotypic direct and indirect effects were higher than the phenotypic direct and indirect effects; this indicated that the other traits had a strong genetically inherited relationship with seed yield. Genotypic path coefficient analysis revealed that days to flowering, biomass and harvest index at Miesso, and seed thickness, plant height, days to maturity and biomass at Melkassa had relatively high positive direct effect on seed yield. However, seed width and hundred seed weight had exerted negative direct effect on seed yield at each location. Phenotypic path coefficient analysis showed that biomass and harvest index had exerted high positive direct effect on seed yield at both locations. From these results it can be concluded from this study that seed yield in cowpea can be improved by focusing on traits pod length, seed length, seed thickness, seed width, biomass and harvest index at both locations. The information obtained from this study can be used for genetic enhancement of cowpea thereby developing high yielding varieties

    Genotype by environment interaction and grain yield stability of drought tolerant cowpea landraces in Ethiopia

    Get PDF
    Open Access Article; Published online: 12 Apr 2022Cowpea is one of the most important indigenous food and forage legumes in Africa. It serves as a primary source of protein for poor farmers in drought-prone areas of Ethiopia. The crop is used as a source of food, and insurance crop during the dry season. Cowpea is adaptable to a wide range of climatic conditions. Despite this, the yield of the crop is generally low due to lack of stable and drought-tolerant varieties. In this study, 25 cowpea genotypes were evaluated in five environments using a lattice design during the 2017 and 2018 main cropping seasons. The objectives of this study were to estimate the magnitude of genotype by environment interaction (GEI) and grain yield stability of selected drought-tolerant cowpea genotypes across different environments. The additive main effect and multiplicative interaction (AMMI) model indicated the contribution of environment, genotype and GEI as 63.98, 2.66% and 16.30% of the total variation for grain yield, respectively. The IPCA1, IPCA2 and IPCA3 were all significant and explained 45.47%, 28.05% and 16.59% of the GEI variation, respectively. The results from AMMI, cultivar superior measure, genotype plus genotype-by-environment biplot yield stability index, and AMMI stability value analyses identified NLLP-CPC-07-145-21, NLLP-CPC-103-B and NLLP_CPC-07-54 as stable and high yielding genotypes across environments. Thus, these genotypes should be recommended for release for production in drought-prone areas. NLLP-CPC-07-143, Kanketi and CP-EXTERETIS were the least stable. The AMMI1 biplot showed that Jinka was a high potential and favorable environment while Babile was an unfavorable environment for cowpea production

    Interlaboratory comparison of methodologies for measuring the angle of incidence dependence of solar cells

    Get PDF
    The aim of this work is to compare angle of incidence (AOI) measurement setups for solar cells between laboratories with such capability. For the first time, we compare relative light transmission measurements among eight laboratories, whose measurement techniques include indoor and outdoor methods. We present the relative transmission measurements on three 156 mm x 156 mm crystalline-Si (c-Si) samples with different surface textures. The measurements are compared using the expanded uncertainties provided by each laboratory. Five of the eight labs showed an agreement better than ±2% to the weighted mean between AOIs from -75° to 70°. At AOIs of ±80° and ±85°, the same five labs showed a worst case deviation to the weighted mean of -3% to 5% and 0% to 18%, respectively. When measurement uncertainty is considered, the results show that measurements at the highest incidence angle of ±85° are problematic, as measurements from four out of the six labs reporting uncertainty were found non-comparable within their stated uncertainties. At 85° AOI a high to low range of up to 75% was observed between all eight laboratories

    Comparison of measures of marker informativeness for ancestry and admixture mapping

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Admixture mapping is a powerful gene mapping approach for an admixed population formed from ancestral populations with different allele frequencies. The power of this method relies on the ability of ancestry informative markers (AIMs) to infer ancestry along the chromosomes of admixed individuals. In this study, more than one million SNPs from HapMap databases and simulated data have been interrogated in admixed populations using various measures of ancestry informativeness: Fisher Information Content (FIC), Shannon Information Content (SIC), F statistics (F<sub>ST</sub>), Informativeness for Assignment Measure (I<sub>n</sub>), and the Absolute Allele Frequency Differences (delta, δ). The objectives are to compare these measures of informativeness to select SNP markers for ancestry inference, and to determine the accuracy of AIM panels selected by each measure in estimating the contributions of the ancestors to the admixed population.</p> <p>Results</p> <p>F<sub>ST </sub>and I<sub>n </sub>had the highest Spearman correlation and the best agreement as measured by Kappa statistics based on deciles. Although the different measures of marker informativeness performed comparably well, analyses based on the top 1 to 10% ranked informative markers of simulated data showed that I<sub>n </sub>was better in estimating ancestry for an admixed population.</p> <p>Conclusions</p> <p>Although millions of SNPs have been identified, only a small subset needs to be genotyped in order to accurately predict ancestry with a minimal error rate in a cost-effective manner. In this article, we compared various methods for selecting ancestry informative SNPs using simulations as well as SNP genotype data from samples of admixed populations and showed that the I<sub>n </sub>measure estimates ancestry proportion (in an admixed population) with lower bias and mean square error.</p

    The weakest link: competence and prestige as constraints to referral by isolated nurses in rural Niger

    Get PDF
    BACKGROUND: For a health district to function referral from health centres to district hospitals is critical. In many developing countries referral systems perform well below expectations. Niger is not an exception in this matter. Beyond obvious problems of cost and access this study shows to what extent the behaviour of the health worker in its interaction with the patient can be a barrier of its own. METHODS: Information was triangulated from three sources in two rural districts in Niger: first, 46 semi-structured interviews with health centre nurses; second, 42 focus group discussions with an average of 12 participants – patients, relatives of patients and others; third, 231 semi-structured interviews with referred patients. RESULTS: Passive patients without 'voice' reinforce authoritarian attitudes of health centre staff. The latter appear reluctant to refer because they see little added value in referral and fear loss of power and prestige. As a result staff communicates poorly and show little eagerness to convince reluctant patients and families to accept referral proposals. CONCLUSIONS: Diminishing referral costs and distance barriers is not enough to correct failing referral systems. There is also a need for investment in district hospitals to make referrals visibly worthwhile and for professional upgrading of the human resources at the first contact level, so as to allow for more effective referral patterns
    corecore