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Ethiopian Journal of Science and Technology
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Print) 2312-6019
Published by African Journals Online Homepage  [261 journals]
  • Genetic variation of LEI0258 locus at major histocompatibility complex
           (MHC) region in Ethiopian indigenous village chicken

    • Authors: Adebabay Kebede , Kassahun Tesfaye, Gurja Belay, Martina Kyallo, Dedan Githae, Tadelle Dessie, Nick Sparks, Oliver Hanotte, Roger Pelle
      Pages: 209 - 237
      Abstract:   Indigenous chickens are locally adapted to environmental challenges and provide subsistence to millions of farmers in Africa.  However, their productivity remains low compared to exotic strains. Efforts are being made to combine the local adaptation of indigenous chicken with productive traits of exotic chicken. Understanding the link between genetic diversity and environmental challenges leads to marker-assisted breed improvement programs for sustainable chicken production at smallholder level. Genetic variation at LEI0258 VNTR locus located within the MHC region has been linked to infectious disease resistance/susceptibility in commercial breeds. The aim of this study was to investigate allelic variability, genetic diversity and genetic relationships of 24 chicken populations in Ethiopia. Here, the diversity at LEI0258 in 236 chickens from 24 Ethiopian indigenous chicken populations using the major Histo-compatibility Complex linked LEI0258 marker is reported. A total of 236 DNA samples were genotyped by capillary electrophoresis from 24 chicken populations. The number of alleles, allele frequency, and heterozygosity levels were used to measure genetic variation at LEI0258 locus in Ethiopian indigenous village chicken. Twenty-nine LEI0258 alleles were observed using capillary electrophoresis that ranged from 185 to 569 bp with no significant difference in allele frequencies between populations.  The number of alleles ranged from 179 (Meseret) to 569 (Batambie), with an average of 9.6 alleles per population. Allelic polymorphism was further evaluated through genotyping by Sanger sequencing. Twenty-three DNA samples with different fragment sizes were re-amplified and their alleles sequenced to depict polympormisms based on the combination of two repeat regions at 12 bp and 13 bp, respectively, and flanking regions with SNP and indels. The repeat region at 12 bp appeared 2 to 18 times, whereas the region at 13 bp appeared invariant in all populations. Sequence relationships revealed two distinct groups of alleles. The number of indels and mutations were 33 and 17, respectively. From capillary electrophoresis, the fixation coefficient of the sub-population within the total population (FST), inbreeding/fixation/ coefficient of an individual in a sub population (FIS) and total inbreeding /heterozygosity deficit/ coefficient of an individual within the total population (FIT) in the locus was 0.03, 0.08 and 0.11, respectively. Three percent of the genetic diversity was due to differences among populations, where as 8% and 89% were variations among individuals and variations within individuals, respectively. Despite the overall low genetic differentiation, both fragment and sequencing analysis revealed high allelic and genetic variability across the 24 populations. The high diversity at LEI0258 in Ethiopian indigenous village chicken populations supports the importance of the MHC region in relation to the disease challenges faced by smallholder poultry farmers across Ethiopia. We recommend that breed improvement programs ensure the maintenance of this diversity by selecting breeding stock as diverse as possible at the LEI0258 locus. 
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
  • Performance of solar panels at various depths in stationary water

    • Authors: Munala Yobes, Sebastian Waita , Geoffrey Okeng’o
      Pages: 239 - 253
      Abstract: Photovoltaic Solar systems have become attractive for powering autonomous systems and various devices. So far, the installation and usage of solar photovoltaic systems has been limited to either land or space. Lately, underwater solar photovoltaic power generation has attracted interest due to some of its unique application in powering underwater devices. The thermal control and cooling that result makes it more dependable for underwater devices. Around the equator, and some other parts of the world, some regions can be quite hot compromising a panel performance. A systematic study on the performance of stationary under water panel using normal tap water would provide information on the applicability of underwater panels in such places. In this work, a detailed study was carried out to determine the performance of 20W monocrystalline photovoltaic solar panels locally acquired and placed at various water depths. A locally purchased plastic translucent water tank was filled with normal tap water and the panels placed in the water at various depths. Solar irradiance, ambient and panel temperature were obtained using a solar 02 device and an irradiance power meter which were connected to a solar current-voltage (I-V) analyzer. Data was collected at 30-minute intervals between 11:00 a.m. and 3:00 p.m. East African Time (EAT) for panels at different depths up to 0.6m. The results revealed that as the water depth increased form 0 m to 0.6m, the panel temperature reduced by 15.48% (at a rate of 0.062 °C/cm), ambient temperature decreased by 5.13%, solar irradiance decreased by 63.79% while power output decreased by 75.00 %. It was noted that the submerged photovoltaic panels reduced the cleaning problem and power loss caused by high temperature. However, positioning the panels deep reduces the power production due to decreased irradiance which has a strong effect on the photocurrent and hence the power production of the panel. It is therefore advisable to keep the panels just below the water surface to maximize power production. The set up can be applied in very hot places for better power production.
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
  • Orange-fleshed sweet potato [Ipomoea batatas (L.) Lam] genotype by
           environment interaction for yield and yield components and SPVD resistance
           under arid and semi-arid climate of northern Ethiopia

    • Authors: Gloria Peace Lamaro, Yemane Tsehaye, Atkilt Girma
      Pages: 255 - 276
      Abstract: Worldwide, sweet potato (Ipomoea batatas (L.) Lam) ranks the sixth most important crop valued for food security, income, and nutritious diet for poor farming communities. Despite its importance, there is lack of information and knowledge to introduce the crop to Afar region where malnourishment is high. Six orange-fleshed sweet potato genotypes (Amelia, Erica, Gloria, Ininda, Kulfo, and Melinda were evaluated for sweet potato viral disease (SPVD), yield and yield components in three contrasting locations, namely Aba’ala, Mekelle 1, and Mekelle 2 using a Randomized Complete Block Design to produce variance components. Joint regression, and additive main effects and multiplicative interactions were used to test the Genotype × Location Interactions (GEI). Means for significant traits were separated by Least Significant Difference (p<0.05). Results showed ample genetic variability for total tuberous yield (TTY), and SPVD resistance. Genotypes Ininda, Gloria, Amelia, and Kulfo were superior for TTY with high SPVD resistance. Aba’ala was a hotspot for SPVD, Mekelle 2 was with low SPVD and recorded a high mean TTY. Amelia and Kulfo exhibited static stability, Ininda and Gloria displayed dynamic stability, high harvest index, and fresh vine yield, and were recommended for further stability investigations. The information generated in this study may be useful as preliminary data however, the experiment has to be repeated for practical conclusions and recommendation of stable varieties for the studied agro-climatic zones.
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
  • Growth performance and feed utilization of Hubbard Classic chickens fed on
           boiled and sundried mango (Mangifera indica Linn.) seed kernel

    • Authors: Yasin Beriso, Berhan Tamir, Etalem Tesfaye
      Pages: 277 - 292
      Abstract: An investigation was undertaken to study the effects of feeding boiled mango seed kernel (BMSK) on the growth performance and feed utilization parameters of Hubbard broiler chicks with the objective of recommending the optimum level of mango seed kernel inclusion in broiler feed. The experiment was arranged in a completely randomized design with four treatments, each replicated three times with 13 birds each. One-hundred fifty-six-day-old chicks with uniform body weight (BW) were used and were distributed randomly to the four diets. The four treatment diets were control (T1) (100% maize + 0% BMSK), T2 (95% maize + 5% BMSK), T3 (90% maize + 10% BMSK) and T4 (85% maize + 15% BMSK). All the experimental chickens were weighted initially (initial BW) and lasted for 49 days during which growth performance traits were recorded. After 49 days, two birds from each replication were randomly selected and slaughtered to evaluate the effect of BMSK on the final body weight of the chicks. The results on average daily feed intake per bird for T1 and T2 were not significantly different, i.e., 71.4 and 70.8 g (P>0.05) but it was significantly higher than that of T3 and T4 which was 68.13 and 68.23 g. At the end of 7 weeks, the final BW of chicks fed on T1 and T2 were 2657 and 2644, not significantly different, but were significantly higher than that of T3 and T4 which were 2610 and 2603 g per bird, respectively. The Average daily BW gain (ADG) for the respective T1 and T2 was 53.4, 53.2 g and was significantly (P<0.05) higher than that of T3 and T4 which were 52.44 and 52.31 g per bird. The feed conversion ratio (g feed/g gain) for T1 and T2 was 1.36, 1.36 and was significantly higher than that of T3 and T4 which were 1.33 and 1.33 g per bird, respectively. Inclusion of mango seed kernel up to 15% in broiler nutrition has no detrimental effect, profitable and can be best alternative feed sources in broiler feed if treated well by using the best technical methods of anti-nutritional factors like boiling.
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
  • Voltammetric determination of paracetamol at glycine modified carbon paste

    • Authors: Yonas Beyene Yohannes, Aragaw Nega Mekonnen, Mekuriaw Assefa
      Pages: 293 - 311
      Abstract: The lower body tolerance of paracetamol (PCT) is 50 ppm and if it surpasses; PCT will led to accumulation of toxic metabolites. A carbon paste electrode modified with glycine (GlyCPE) is used for the detection of PCT at relatively low concentrations. In contrast to the bare carbon paste electrode (CPE), an improved onset potential with a shifting of 85 mV and enhancement of anodic peak current at the modified electrode resulted in a the GlyCPE surface with a material that possesses an electroanalytical activity toward the oxidation of PCT. Differential pulse stripping voltammograms (DPSV) of PCT oxidation on the GlyCPE yielded a well-defined oxidation peak of 0.61 V in a 0.1 M phosphate buffer solution of pH 6.0 with a linear calibration from 5.0 to 1000 mM with R2 = 0.995. The DPSV detection limit was projected to be 0.12 mM. In the presence of the interfering ascorbic acid (AA) of 50 and 100 mM, the GlyCPE was able to detect the PCT (100 mM) with a percentage of detection of 100.16 and 97.79, respectively, which did not affect significantly the peak current response of the PCT. Besides, the fabricated GlyCPE accurately measured the amount of PCT in three brand pharmaceutical samples.
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
  • Plasmodium berghei infection associated with adverse birth outcomes in
           pregnant Swiss albino mice

    • Authors: David Audu, Olufunmilayo Ajoke Idowu, Adewumi Babatunde Idowu
      Pages: 313 - 324
      Abstract: Malaria in pregnancy has been seen to cause poor pregnancy and foetal outcomes. In this study, mice infected with Plasmodium berghei (P. berghei) during the second and third stages of pregnancy were examined for their pregnancy's outcome and changes in their blood's biochemical composition after delivery. Additionally, the physical and behavioural reactions of the mice's pups were also investigated. Thirty pregnant female Swiss Albino mice were randomly divided into three groups; two received intraperitoneal injections of 106 P. berghei-infected red blood cells on gestational days (GD12 and 17), while the third group was left uninfected (control). Pregnancy termination occurred in 20% of mice infected during GD12, whereas mortality before parturition occurred in 40% and 30% of mice infected during GD12 and GD17, respectively. Non-infected group's total protein and glucose concentrations were significantly higher (p<0.05), while cholesterol and triglyceride concentrations were significantly lower (p<0.05) when compared to the infected groups. The Mean birth weights (1.82 ± 0.37 g) of pups were considerably higher (p < 0.05) in control mice compared to pups from infected groups. Offspring born to infected mothers exhibited poor physical and behavioural responses. Mice infection by Plasmodium berghei during pregnancy resulted in adverse birth outcomes, altered measured biochemical parameters, poor physical and behavioural responses in their offspring and was more severe during the 2nd stage of pregnancy.
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
  • Impact of convection on three dimensional Casson rotatory fluid over an
           extending sheet: A numerical approach

    • Authors: Alfunsa Prathiba, A. Venkata Lakshimi
      Pages: 325 - 340
      Abstract: Natural convection occurs in fluid environments. Usually, it is facilitated by the buoyancy effect. It is significantly less efficient than forced convection, due to the lack of fluid motion. As a result, it is completely dependent on the buoyancy effect's strength and the fluid's viscosity. The current work investigates the convective flow of a three-dimensional Casson fluid across a rotating linear expanding sheet. The nonlinear governing equations of the steady flow were presented and reconstructed using appropriate similarity transformations. To solve the resultant equations, the three-stage collocation approach namely Lobatto IIIA was applied using MATLAB. Graphs were used to illustrate the physical properties of the required data. It was observed that while the primary velocity profile decreases as the Casson, convective, and rotational parameters increase, the secondary velocity profile exhibits the opposite behaviour. The effect of rotation, Casson parameter, and others on drag coefficient, heat transfer coefficient, and mass transfer coefficient was evaluated, interpreted, and found to be reasonably consistent with earlier research.
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
  • Forensic appraisal of leg length as a predictor for determination of
           Nigerian students’ body height

    • Authors: Adekunle I. Musa, Temitayo S. Ogedengbe, Ademola E. Adeleke, Abiola O. Ajayeoba, Syed M. Qutubuddin, Imhade P. Okokpujie
      Pages: 341 - 350
      Abstract: Appraisal of body height (Bh) from leg length (LL) and other anthropometric parts of an individual is very important in the identification of human skeletal remains. The objective of this study was to develop a model for the estimation of Bhmale, Bhfemale and Bhcombined. The study was conducted in three selected tertiary institutions in Southwest Nigeria with a total of 324 students (162 male and 162 female) using the snowball techniques where the Bh and LL of the students were measured using stadiometer and sliding caliper. The data were analysed statistically using statistical package for social sciences v 21 software. The result showed mean values of 168.49 ± 9.19 cm of Bhmale, 168.15 ± 8.66 cm Bhfemale and 168.32±8.91 cm Bhcombined. Similarly, the mean values of 96.40±7.29 cm LLmale, 96.27±6.96 cm LLfemale and 96.33 ± 7.12 cm LLcombined were found. Furthermore, the coefficient of determination, R2 was determined as 76.0%, 19.1% and 44.3%, respectively. Three regression models were formulated to determine the Bhmale, Bhfemale and Bhcombined with LLmale, LLfemale and LLcombined as the predictors. It was concluded that this formulated model could be a veritable tool for the development of forensic anthropological studies for Nigerian student population.
      PubDate: 2022-11-07
      DOI: 10.4314/ejst.v15i3.
      Issue No: Vol. 15, No. 3 (2022)
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