Biology subjects

Shibru, S.

Publications and source records attributed to Shibru, S..

3 recordsLinked to original sources

bioRxiv2021

Effects of land-use and landscape drivers in the species richness and distribution of carnivores in Faragosa-Fura Landscape of Southern Rift Valley, Ethiopia

Understanding the species richness and distribution of carnivores across anthropogenic land-use types in an area is an essential first step for biodiversity conservation and human-carnivore coexistence. However, quantitative data on carnivore species coexisting with humans in different land-use types remain largely missing. Thus, this paper investigated the effect of anthropogenic land-use and landscape drivers on carnivore species richness and distribution in the Faragosa-Fura Landscape, Gamo Zone, southern Ethiopia. To collect data, we employed the line transect method using three complementary field surveys techniques: sign survey, camera-trapping, and opportunistic sighting survey during wet and dry seasons in 2020 and 2021. We stratified the study landscape into five land-use types-forest, wetland, grassland, agricultural land, and settlement. The result proved the occurrence of 12 carnivore species belonging to six families, including vulnerable Felidae species - Panthera pardus. Family Felidae and Herpestidae were composed of a greater number of species, while Hyaenidae and Mustelidae were each represented by single species. Out of identified species, only two species (Panthera pardus and Crocuta crocuta) were large-sized, while the rest were medium and small-sized carnivores. Overall, the mean richness of the study area was 5.73{+/-}0.284(SE). The species richness was highest in the wetland (n = 12, mean = 7.67{+/-}0.494(SE)) and lowest in the settlement (n = 5, mean = 4.25{+/-}0.479(SE)). The regression analysis showed that most of the carnivores displayed a strong negative relationship with agriculture, roads, and settlement while displayed a strong positive relationship with wetland and forest. In general, out of 32 species recorded in Ethiopia, this study quantified 12 carnivore species that signify the area is an important area for wildlife conservation in Ethiopia. Further, the study concluded that the wetland is the most important habitat, particularly for larger-sized and habitat specialists while anthropogenic land-uses types adversely affecting species richness. Thus, a generic paradigm to reconcile land management and biodiversity conservation is highly important.

ecology↗

bioRxiv2021

Population Status and Habitat Association of Swaynes Hartebeest (Alcelaphus Buselaphus Swaynei (Sclater, 1892)) in Maze National Park, Southern Ethiopia

We investigated the population status and habitat association of the endemic Swaynes Hartebeest (Alcelaphus buselaphus swaynei (Sclater, 1892)) in Maze National Park, Southern Ethiopia, in 2018 and 2019. Sample count method line-transect was used for the population estimation, while habitat association was made based on the abundance of individuals counted in each habitat. Data were analyzed using descriptive statistics and compared with {chi}2 test. The total estimated populations of Swaynes Hartebeest (SHB) in the study period were 1456 and 1492 during wet and dry seasons, respectively showing no seasonal variation. Among the total estimated population, 31% were adult males, 38.46% adult females, 13.97% sub adult males, 15.94% sub adult females and 1.07% young. The number of adult females was higher than the other age groups followed by adult males in both seasons. Significant differences were reported among age and sex structure of population size during both seasons (wet season: {chi}2= 58.423, df =3, P < 0.05; dry season: {chi}2=534.079, df= 4, P < 0.05). The maximum group size was 36 and the minimum was 1. The ratio of adult males to adult females was 1:1.24 and 1:1.24, sub-adult males to sub adult females was 1:1.16 and 1:1.12, adult males to sub-adult males was 1:0.36 and 1:0.56, adult females to sub-adult females was 1:0.33 and 1:0.49 in the wet and dry seasons, respectively. The male to female ratio was 1:1.22 and 1:1.19 during wet and dry seasons as well. The population trend among ten years were significantly differed ({chi}2 = 1.708, df= 9, P< 0.05). The SHB was distributed into three types of habitat (riverine forest, open grassland and scattered tree) with significant differences ({chi}2=1109.937, df = 3, P < 0.05). The savannah grass land was most preferable habitat followed by scattered tree habitat. Maintaining its critical habitat was highly recommended for sustainability of current population status.

zoology↗

bioRxiv2020

Evaluation of a pan-Leishmania SL-RNA qPCR assay for parasite detection in laboratory-reared and field-collected sand flies and reservoir hosts.

BackgroundIn eco-epidemiological studies, Leishmania detection in vectors and reservoirs is frequently accomplished by high-throughput and sensitive molecular methods that target minicircle kinetoplast DNA (kDNA). A pan-Leishmania SYBR Green quantitative PCR (qPCR) assay which specifically detects the conserved spliced-leader RNA (SL-RNA) sequence has recently been developed. This study comparatively assessed the SL-RNA assay performance for the detection of Leishmania in field and laboratory infected sand flies and in tissue samples from hyraxes as reservoir hosts. Principal findingsThe qPCRs targeting SL-RNA and kDNA performed equally well on infected sand fly samples, despite preservation and extraction under presumed unfavorable conditions for downstream RNA detection. Nucleic acid extraction by a crude extraction buffer combined with a precipitation step was highly compatible with downstream SL-RNA and kDNA detection. Copy numbers of kDNA were found to be identical in culture-derived parasites and promastigotes isolated from sand fly midguts. SL-RNA levels were approximately 3-fold lower in sand fly promastigotes ({Delta}Ct 1.7). The theoretical limit of detection and quantification of the SL-RNA qPCR respectively reached down to 10-3 and 10 parasite equivalents. SL-RNA detection in stored hyrax samples was less efficient with some false negative assay results, most likely due to the long-term tissue storage in absence of RNA stabilizing reagents. ConclusionThis study shows that a crude extraction method in combination with the SL-RNA qPCR assay is suitable for the detection and quantification of Leishmania in sand flies. The assay provides complementary information to the standard kDNA assays, since it is pan-Leishmania specific and detects viable parasites, a prerequisite for identification of vectors and reservoirs. Author summaryIn order to identify vectors and reservoirs of Leishmania, a large number of sand fly and animal tissue samples needs to be screened, because the infection prevalence is generally low. Hence, sensitive low-cost methods are required for nucleic acid isolation and Leishmania detection. Most approaches amplify DNA targets, in particular minicircle kinetoplast DNA (kDNA). Recently, a qPCR was developed that detects the spliced-leader RNA (SL-RNA) sequence, which is conserved among various Leishmania species and allows detection of viable parasites. We show that the SL-RNA qPCR is highly compatible with a low-cost, crude extraction approach and performs equally well on laboratory and field infected sand fly samples as kDNA qPCR assays. The assay can detect 10-3 parasite equivalent in sand flies and enables Leishmania quantification down to 10 parasites. We found that the copy number of SL-RNA is 3-fold lower in sand fly derived promastigotes compared to cultured promastigotes. SL-RNA detection in hyrax tissue samples appeared less efficient, which is presumably due to long-term storage without RNA stabilizing reagents. Overall, our assay is complementary to kDNA assays as it can identify viable Leishmania stages, which provides pivotal information for identification of reservoirs and vectors and their transmission capacity.

microbiology↗