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Abstract: We surveyed small-scale farmers in the Kenyan Rift Valley province (Narok and Nakuru districts) to describe constraints to, and changes in, livestock production and to assess the extent to which farmers have adopted new technologies promoted by extension services. In the arid areas of southern Narok, farmers' main constraints were drought and disease. Farmers in Nakuru district, situated in the fertile highlands of the Rift Valley, were also affected by disease but also lacked markets and capital. Although 83% of the farmers had regular contact with extension services that provided advice on new technologies and livestock production innovations, only about half of the respondents implemented the proposed changes. Many of those who did change (38%) improved pasture/nutrition/manure management and relatively few (16%) improved their animal breeding practices. Results of a multinomial logit model revealed that, apart from the significant differences between the two districts, the nature of the advice and the expected outcomes had the strongest influence on the probability of successfully implementing changes to livestock production. The results further suggest that adoption of new technologies is limited by lack of knowledge, inadequate support and a failure to target local needs and conditions and empower livestock keepers. [Copyright &y& Elsevier]

African sheep manifest diverse but distinct physio-anatomical traits, which are the outcomes of natural- and human-driven selection. Here, we generated 34.8 million variants from 150 indigenous northeast African sheep genomes sequenced at an average depth of ∼54× for 130 samples (Ethiopia, Libya) and ∼20× for 20 samples (Sudan). These represented sheep from diverse environments, tail morphology and post-Neolithic introductions to Africa. Phylogenetic and model-based admixture analysis provided evidence of four genetic groups corresponding to altitudinal geographic origins, tail morphotypes and possible historical introduction and dispersal of the species into and across the continent. Running admixture at higher levels of K (6 ≤ K ≤ 25), revealed cryptic levels of genome intermixing as well as distinct genetic backgrounds in some populations. Comparative genomic analysis identified targets of selection that spanned conserved haplotype structures overlapping clusters of genes and gene families. These were related to hypoxia responses, ear morphology, caudal vertebrae and tail skeleton length, and tail fat-depot structures. Our findings provide novel insights underpinning morphological variation and response to human-driven selection and environmental adaptation in African indigenous sheep. • Northeast Africa sheep are defined by three major genetic backgrounds associated with their introduction in Africa • Natural selection for adaptation to contrasting environments could be drivers of adaptive divergence in African sheep • Skeletal tail associated genes are most likely playing major roles in the unique adaptations of African sheep [ABSTRACT FROM AUTHOR]

• COI divergence among seven rhipicephaline ticks found in Kenya ranges from 9–16%. • R. simus / R. praetextatus / R. muhsamae comprise a closely related tick species complex. • Ruma National Park tick species is genetically related to those of R. simus complex. • Molecular identification is only reliable when well curated reference sequences exist. The morphological diversity of African ticks of the genus Rhipicephalus and subgenus Boophilus have been studied in detail. However, their taxonomy remains poorly resolved with limited molecular studies performed to improve inter-species discrimination. Herein, ribosomal cytochrome c oxidase I (COI), 12S ribosomal DNA (12S rDNA) and nuclear ribosomal DNA internal transcriber spacer 2 (ITS2) were analyzed in Rhipicephalus tick populations in Kenya. While the morphological and molecular criteria separated R. e. evertsi, R. pulchellus and R. appendiculatus from other members of the genus, except the morphologically similar sibling species R. zambeziensis , this was not the case for other tick populations. COI sequences of Rhipicephalus ticks from Ruma National Park (RNP) in Southwestern Kenya, that were morphologically similar to R. praetextatus/R. simus , a formed distinct clade and barcode gap group. 12S rDNA haplotypes of this population were 99% identical to a GenBank accession of R. muhsamae which is thought to be endemic in West and Central Africa. However, the ITS2 locus indicated that the RNP samples were genetically closest to ticks identified morphologically as R. praetextatus. The COI and 12S rDNA haplotype sequences of R. praetextatus clustered closely with R. simus reference sequences though the two species occurred in distinct barcode gap groups. Our results suggest that the R. simus/R. praetextatus / R. muhsamae comprise a closely related tick species complex found across sub-Saharan Africa and includes the yet to be described RNP population. More studies on the biology, ecology and genomics of all life stages of tick species in the complex may clarify their taxonomic status. A continent-wide study that combines morphology, DNA marker sequencing and emerging methods, such as mass spectrometry and whole-genome resequencing may reveal the diversity and distribution of taxa within the genus Rhipicephalus in sub-Saharan Africa. [ABSTRACT FROM AUTHOR]