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Oyola, S. O.

Publications and source records attributed to Oyola, S. O..

2 recordsLinked to original sources

Altitude-dependent agro-ecologies impact the microbiome diversity of scavenging indigenous chicken in Ethiopia

Scavenging indigenous village chickens play a vital role in sub-Saharan Africa, sustaining the livelihood of millions of farmers. These chickens are exposed to vastly different environments and feeds compared to commercial chickens. In this study, we analysed the caecal microbiota of 243 Ethiopian village chickens living in different altitude-dependent agro-ecologies. Differences in bacterial diversity were significantly correlated with differences in specific climate factors, topsoil characteristics, and supplemental diets provided by farmers. Microbiota clustered into 3 enterotypes, with one particularly enriched at high altitudes. We assembled 9,977 taxonomically and functionally diverse metagenome-assembled genomes, the vast majority of which were not found in a dataset of previously published chicken microbes, or in the Genome Taxonomy Database. The wide functional and taxonomic diversity of these microbes highlights their importance in the local adaptation of indigenous poultry, and the significant impacts of environmental factors on the microbiota argues for further discoveries in other agro-ecologies.

microbiology↗

Complete avian malaria parasite genomes reveal host-specific parasite evolution in birds and mammals

Avian malaria parasites are prevalent around the world, and infect a wide diversity of bird species. Here we report the sequencing and analysis of high quality draft genome sequences for two avian malaria species, Plasmodium relictum and Plasmodium gallinaceum. We identify 50 genes that are specific to avian malaria, located in an otherwise conserved core of the genome that shares gene synteny with all other sequenced malaria genomes. Phylogenetic analysis suggests that the avian malaria species form an outgroup to the mammalian Plasmodium species and using amino acid divergence between species, we estimate the avian and mammalian-infective lineages diverged in the order of 10 million years ago. Consistent with their phylogenetic position, we identify orthologs of genes that had previously appeared to be restricted to the clades of parasites containing P. falciparum and P. vivax - the species with the greatest impact on human health. From these orthologs, we explore differential diversifying selection across the genus and show that the avian lineage is remarkable in the extent to which invasion related genes are evolving. The subtelomeres of the P. relictum and P. gallinaceum genomes contain several novel gene families, including an expanded surf multigene family. We also identify an expansion of reticulocyte binding protein homologs in P. relictum and within these proteins, we detect distinct regions that are specific to non-human primate, humans, rodent and avian hosts. For the first time in the Plasmodium lineage we find evidence of transposable elements, including several hundred fragments of LTR-retrotransposons in both species and an apparently complete LTR-retrotransposon in the genome of P. gallinaceum.

genomics↗