Genome-wide genetic diversity, population structure and admixture analysis in Eritrean Indigenous Cattle

Indigenous cattle play a vital role in subsistence and livelihood of pastoral producers in Eritrea. In order to optimally utilize and conserve these valuable indigenous cattle genetic resources, the need to carry out an inventory of their genetic diversity was recognized. This study assessed the genetic variability, population structure and admixture of the indigenous cattle populations (ICPs) of Eritrea using a genotype by sequencing (GBS) approach. The authors genotyped 188 animals, which were sampled from 27 cattle populations in three diverse agro-ecological zones (western lowlands, highlands and eastern lowlands). The genome-wide analysis results from this study revealed genetic diversity, population structure and admixture among the ICPs. Averages of the minor allele frequency (AF), observed heterozygosity (HO), expected heterozygosity (HE), and inbreeding coefficient (FIS) were 0.157, 0.255, 0.218, and -0.089, respectively. Nei’s genetic distance (Ds) between populations ranged from 0.24 to 0.27. Mean population differentiation (FST) ranged from 0.01 to 0.30. Analysis of molecular variance revealed high genetic variation between the populations. Principal component analysis and the distance-based unweighted pair group method and arithmetic mean analyses revealed weak substructure among the populations, separating them into three genetic clusters. However, multi-locus clustering had the lowest cross-validation error when two genetically distinct groups were modelled. This information about genetic diversity and population structure of Eritrean ICPs provided a basis for establishing their conservation and genetic improvement programmes. Keywords: genetic variability, molecular characterization, population differentiatio

Use of E-Books by Undergraduate Students in Public Universities in Kenya

University libraries in Kenya are increasingly relying on e-books for current and up-to-date information. These are also more affordable as they are acquired in bulk through Kenya Library and Information Services Consortium (KLISC). This study was intent on identifying ways in which undergraduate students in public universities in Kenya interact with the e-books. Data was collected in four public universities using mixed methods approach. A survey questionnaire was distributed to 300 third year undergraduate students, while interview schedules were used to guide four undergraduate students’ focus group discussions, interviews with 20 lecturers and 12 library staff. It was found that undergraduate students were largely unskilled in use of e-books; undergraduate students were dependent on reference groups for motivation to use e-books; and e-books qualities made them more favorable over print resources. Recommendations made include awareness creation for reference groups, enhanced library staff capacities, and lecturer involvement. This article is part of a more elaborate study whose findings will enable packaging and delivery of e-books in formats that ensure sustained enhanced use

Formulation of slow release NPK fertilizer (cellulose-graft-poly(acrylamide)/nano-hydroxyapatite/soluble fertilizer) composite and evaluating its N mineralization potential

Polymer nano-composite fertilizer formulation has the potential to enhance nutrient use efficiency. Slow release fertilizer (SRF) composite was formulated by incorporating nano-hydroxyapatite (nano-HA) and water soluble fertilizers (urea, (NH4)2HPO4 and K2SO4) into water hyacinth cellulose-graft-poly(acrylamide) polymer hydrogel. Fourier Transform Infra-red spectra revealed existence of chemical interaction between the monomer, cellulose, urea and nano-HA. The release of nutrients was assessed using laboratory incubation experiment. Significantly higher content of mineral nitrogen (MN) was observed in the first 4 weeks in conventional fertilizer (CF) compared to SRF treatments and the control. MN content in SRF treatments increased considerably between the 8th and 12th week, and declined in the 16th week. The values of potentially mineralizable N estimated using first order kinetics model related well to the observed cumulative MN at 16th week. No significant difference was observed between CF and SRF treatments for available P content in the 2nd week. Significantly higher P content was observed in CF compared to SRF treatment in the 4th week, whereas in the 8th week, some SRFs released significantly higher content than CF. Available P peaked in the 8th week in all the treatments and remained constant at 12th and 16th week. Availability of P in SRFs increased with increased content of soluble P and decreased content of nano-HA. Exchangeable K showed less variation during the incubation period, suggesting short release time. The data revealed reduced chances of leaching losses and toxic effect to the plant roots, as well as synchronized nutrient release and requirement by crops. Keywords: Nano-composite, Polymer hydrogel, Chemical interaction, Incubation experiment, Kinetics mode