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Torsten Wronski - One of the best experts on this subject based on the ideXlab platform.
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dark grey Gazelles gazella cetartiodactyla bovidae in arabia threatened species or domestic pet
Hystrix-italian Journal of Mammalogy, 2017Co-Authors: Torsten Wronski, Hannes Lerp, Eva Verena Baermann, Thomas M Butynski, Martin PlathAbstract:True Gazelles (genus Gazella) are a prime example of a mammalian group with considerable taxonomic confusion. This includes the descriptions of several dark grey taxa of questionable validity. Here, we examined captive dark grey putative Neumann’s Gazelle Gazella erlangeri. Our concerted efforts to retrieve mitochondrial sequence information from old museum specimens of two dark grey Gazelles, putative G. erlangeri and putative Muscat Gazelle G. muscatensis, were unsuccessful. We did, however, find the mtDNA haplotypes of extant putative G. erlangeri to be nested within the haplotype variation of the Arabian Gazelle G. arabica. The observed population genetic divergence between G. arabica and putative G. erlangeri (based on 11 nuclear microsatellites) was driven by genetic impoverishment of putative G. erlangeri. These results, along with morphological signatures of domestication (e.g., reduced brain case size), suggest genetic bottle necks and domestication effects as a consequence of prolonged captive breeding. Three hypotheses are discussed: (a) G. erlangeri and/or G. muscatensis are valid species but are now extinct; (b) one or both taxa represent phenotypic variation within G. arabica and, therefore, are synonyms of G. arabica; and (c) captive stocks, exhibiting the effects of domestication and inbreeding, are the sources for the descriptions of G. erlangeri and G. muscatensis. As concerns the conservation of Gazelles, based on current knowledge, we strongly advise against using putative G. erlangeri for any introduction initiative but recommend the continued captive management of putative G. erlangeri.
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a morphometric and genetic framework for the genus gazella de blainville 1816 ruminantia bovidae with special focus on arabian and levantine mountain Gazelles
Zoological Journal of the Linnean Society, 2013Co-Authors: Torsten Wronski, Eva V. Bärmann, Saskia Börner, Dirk Erpenbeck, Gertrud E. Rössner, Hannes Lerp, Beatriz Azanza, Gert WörheideAbstract:Gazella is one of the most species-rich genera within horned ruminants. Despite overall similarity in body size and morphology, Gazelles show variability in coloration and horn morphology. Unfortunately, however, species differentiation based on these characters, or on discrete skull characters, is very difficult due to high intraspecific variability. Furthermore, most species have fragmented and allopatric distributions, so that species boundaries were hard to define in the past. Mitochondrial DNA sequences have proven useful for investigating Gazelle taxonomy in recent years, but especially for old museum material, i.e. type specimens, destructive sampling is often impossible. We provide a comprehensive morphometric framework for the genus Gazella based on linear skull measurements reconciled with results from molecular phylogenetic analysis based on the largest dataset available so far. In particular for males, the skull morphology shows interspecific differences concurrent with DNA data and provides a reliable tool for species identification. Based on morphometric data we synonymize G. karamii with G. marica, and confirm the identification of the G. arabica and G. a. rueppelli type skulls from analyses of mitochondrial DNA sequences. © 2013 The Linnean Society of London
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cross infection with gastro intestinal tract parasites between domestic goat and endemic farasan Gazelle gazella gazella farasani in farasan islands saudi arabia
Journal of King Saud University - Science, 2013Co-Authors: Ann Apio, Sawsan A. Omer, Osama B. Mohammed, Torsten WronskiAbstract:Abstract Host related variations in helminth egg and coccidian oocyst counts were compared between a naturally infected endemic population of Farasan Gazelle and domestic goats on the Farasan Islands, Saudi Arabia in April 2009. Both bovid species inhabit and browse in the same area but no cross-infection could be detected. The prevalence and mean intensity quantified as the number of eggs and oocysts per gram of faeces were taken as a measure of parasite burdens. Host related differences in prevalence values of Eimeria spp. were significantly higher in domestic goats than in wild Gazelles. A similar trend was observed for nematode prevalence (strongyle-type eggs), with no infection in Gazelle and low infection in goats. There was also a significant difference in mean intensity values between different Eimeria spp. found in domestic goats.
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population development of arabian Gazelles gazella arabica on the farasan islands saudi arabia mammalia bovidae
Zoology in The Middle East, 2013Co-Authors: Torsten WronskiAbstract:The population of the Arabian Gazelle (Gazella arabica) was assessed on Farasan Kebir, the main island of the Farasan Archipelago (Saudi Arabia), from June 2010 to January 2013, using road strip counts. Two methods of estimating the population size were applied to analyse data obtained from the road strip count: (i) the traditional technique after Bothma, with a fixed strip width, and (ii) distance sampling using DISTANCE 6.0. Estimates varied between 483 Gazelles (95% CI: 44) in November 2010 and 1070 Gazelles (95% CI: 63) in June 2010. The number of Gazelles estimated for Farasan Kebir using distance sampling is 2388 Gazelles (95% CI: 921) in December 2011, 1199 Gazelles (95% CI: 1372) in June 2012, and 1048 Gazelles (95% CI:1524) in January 2013. Taking into account previous counts (1988–2009) the population seems, despite considerable variations, surprisingly stable. This may be attributed to a prevailing fishing culture among local residents and thus the absence of traditional hunting as well as the ...
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size and sex matter reproductive biology and determinants of offspring survival in gazella marica
Biological Journal of The Linnean Society, 2013Co-Authors: Rudiger Riesch, Martin Plath, Hannes Lerp, Ryan Martin, Torsten WronskiAbstract:Environmental conditions should impact the optimal resolution of the trade-off between offspring size and offspring number, which has a major impact on female reproductive life histories. Using breeding data collected over 13 years at the King Khalid Wildlife Research Centre (KKWRC) in Saudi Arabia, we tested the hypothesis that larger sand Gazelle (Gazella marica) offspring will have lower mortality than smaller-sized offspring; nonetheless, selection should still favour the production of larger litters (even at the cost of reduced offspring size) under favourable environmental conditions (and vice versa under poor environmental conditions). The present study provides evidence for an early fitness advantage of larger over smaller sand Gazelles because offspring that were heavier at birth had higher survival rates to weaning age (90 days) and sexual maturity (365 days) than lighter offspring; also, females had higher survival rates than males. Moreover, antagonistic selection on offspring and litter size is resolved in favour of maternal fitness early in the year (i.e. high propensity for twinning), although fitness optima converge later in the year when it becomes beneficial to both offspring and mothers to produce large singletons, highlighting temporal variation in the selective regimes affecting female reproductive life histories. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110, 116–127.
Osama B. Mohammed - One of the best experts on this subject based on the ideXlab platform.
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cross infection with gastro intestinal tract parasites between domestic goat and endemic farasan Gazelle gazella gazella farasani in farasan islands saudi arabia
Journal of King Saud University - Science, 2013Co-Authors: Ann Apio, Sawsan A. Omer, Osama B. Mohammed, Torsten WronskiAbstract:Abstract Host related variations in helminth egg and coccidian oocyst counts were compared between a naturally infected endemic population of Farasan Gazelle and domestic goats on the Farasan Islands, Saudi Arabia in April 2009. Both bovid species inhabit and browse in the same area but no cross-infection could be detected. The prevalence and mean intensity quantified as the number of eggs and oocysts per gram of faeces were taken as a measure of parasite burdens. Host related differences in prevalence values of Eimeria spp. were significantly higher in domestic goats than in wild Gazelles. A similar trend was observed for nematode prevalence (strongyle-type eggs), with no infection in Gazelle and low infection in goats. There was also a significant difference in mean intensity values between different Eimeria spp. found in domestic goats.
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coagulation profile and platelet parameters of the arabian sand Gazelle gazella subgutturosa marica comparison with humans and camels
Journal of Wildlife Diseases, 2010Co-Authors: Mansour F. Hussein, Osama B. Mohammed, Sawsan A. Omer, Riyadh S. Aljumaah, M. A. Alshaikh, Abdelgadir Homeida, A Alhaidary, A Gar R Elnabi, William MacaseroAbstract:During March 2009, we evaluated the hemostatic profile and platelet indices of 18 Arabian sand Gazelles (Gazella subgutturosa marica) and compared the results with those from humans and camels (Camelus dromedarius). Gazelles and camels had shorter activated partial thromboplastin times, lower proconvertin and higher antihemophilic factor coagulation activity, and plasma fibrinogen levels than humans. Prothrombin time was longer in sand Gazelles and shorter in camels than it was in humans. Plasma thromboplastin component, Stuart factor, and plasma thromboplastin antecedent were similar in Gazelles, humans, and camels, whereas the platelet count of the sand Gazelle was significantly higher than it was for camels and humans.
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the efficacy of ivermectin and levamisole against natural nematodirus spathiger infection in the arabian sand Gazelle gazella subgutturosa marica and the arabian mountain Gazelle gazella gazella in saudi arabia
Veterinary Parasitology, 2007Co-Authors: Osama B. Mohammed, Sawsan A. Omer, Mohammed A. SandoukaAbstract:The efficacy of two broad spectrum anthelmintics (Ivermectin and Levamisole) against the nematode Nematodirus spathiger in the reem (Arabian sand Gazelle) and idmi (Arabian mountain Gazelle) at King Khalid Wildlife Research Centre (KKWRC) was determined. Gazelles of both species naturally infected with N. spathiger were each divided into 3 groups. One group was treated with Ivermectin, the other group with Levamisole and the last group was left as untreated control. Faecal egg counts were employed to determine the efficacy of the two drugs against N. spathiger infection in both Gazelle species. Reduction in arithmetic mean faecal egg counts achieved by Ivermectin and Levamisole in the reem Gazelles was 94% and 89.3%, respectively. The reduction in the idmi Gazelles was 97.2% and 96.4%, respectively. Hence, both anthelmintics appeared to be more effective in the idmi Gazelles than in the reem Gazelles, however, there was no significant difference in the faecal egg reduction tests in both animal species.
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HAMMONDIA HEYDORNI FROM THE ARABIAN MOUNTAIN Gazelle AND RED FOX IN
2003Co-Authors: Saudi Arabia, Osama B. Mohammed, Angela J. Davies, Hussein S. Husseint, Peter Daszak, John EllisAbstract:Unsporulated oocysts were detected in the feces of an Arabian red fox (Vulpes vulpes arabica) between 6 and 8 days after it had been fed meat from Arabian mountain Gazelles (Gazella gazella) known to contain sarcocysts. No oocysts were discovered in the feces of other experimental cubs, although sporocysts of Sarcocystis spp. were passed subsequently by all cubs that were fed Gazelle meat, including those fed with reem (G. subgutturosa marica). The oocysts sporulated in 3 days at room temperature (25 ?_ 2 C); they were 10.9 ?+ 1.4 X 10.1 ?_ 1.3 pm, with 2 sporocysts measuring 6.0 + 0.6 X 4.7 ?_ 0.8 pm, each with 4 sporozoites. Sporulated oocysts were identified as those of Hammondia heydorni using molecular and standard morpho- metric techniques. Sequence differences between 2 fox and 3 dog isolates of H. heydorni were detected and allowed differentiation between the 2 populations of the organism. The involvement of Neospora caninum was excluded using molecular methods. The Arabian red fox and the Arabian mountain Gazelle in Saudi Arabia are new, definitive and intermediate hosts for H. heydorni. Hammondia heydorni (Tadros and Laarman, 1976) Dubey, 1977 is a heteroxenous intestinal coccidium of canines, with a
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Hammondia heydorni from the arabian mountain Gazelle and red fox in Saudi Arabia
The Journal of parasitology, 2003Co-Authors: Osama B. Mohammed, Hussein S. Hussein, Angela J. Davies, Peter Daszak, John EllisAbstract:Unsporulated oocysts were detected in the feces of an Arabian red fox (Vulpes vulpes arabica) between 6 and 8 days after it had been fed meat from Arabian mountain Gazelles (Gazella gazella) known to contain sarcocysts. No oocysts were discovered in the feces of other experimental cubs, although sporocysts of Sarcocystis spp. were passed subsequently by all cubs that were fed Gazelle meat, including those fed with reem (G. subgutturosa marica). The oocysts sporulated in 3 days at room temperature (25 ± 2 C); they were 10.9 ± 1.4 × 10.1 ± 1.3 μm, with 2 sporocysts measuring 6.0 ± 0.6 × 4.7 ± 0.8 μm, each with 4 sporozoites. Sporulated oocysts were identified as those of Hammondia heydorni using molecular and standard morphometric techniques. Sequence differences between 2 fox and 3 dog isolates of H. heydorni were detected and allowed differentiation between the 2 populations of the organism. The involvement of Neospora caninum was excluded using molecular methods. The Arabian red fox and the Arabian mount...
Eduardo R S Roldan - One of the best experts on this subject based on the ideXlab platform.
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germ cell survival and differentiation after xenotransplantation of testis tissue from three endangered species iberian lynx lynx pardinus cuvier s Gazelle gazella cuvieri and mohor Gazelle g dama mhorr
Reproduction Fertility and Development, 2014Co-Authors: Lucía Arregui, Ina Dobrinski, Eduardo R S RoldanAbstract:The use of assisted reproductive techniques for endangered species is a major goal for conservation. One of these techniques, testis tissue xenografting, allows for the development of spermatozoa from animals that die before reaching sexual maturity. To assess the potential use of this technique with endangered species, testis tissue from six Iberian lynxes (one fetus, two perinatal cubs, two 6-month-old and one 2-year-old lynx), two Cuvier's Gazelle fetuses and one 8-month-old Mohor Gazelle were transplanted ectopically into nude mice. Tissue from the lynx fetus, perinatal cubs and 2-year-old donors degenerated, whereas spermatogonia were present in 15% of seminiferous tubules more than 70 weeks after grafting in transplanted testis tissue from 6-month-old donors. Seminal vesicle weights (indicative of testosterone production) increased over time in mice transplanted with tissue from 6-month-old lynxes. Progression of spermatogenesis was observed in xenografts from Gazelles and was donor age dependent. Tissue from Cuvier's Gazelle fetuses contained spermatocytes 40 weeks after grafting. Finally, round spermatids were found 28 weeks after transplantation in grafts from the 8-month-old Mohor Gazelle. This is the first time that xenotransplantation of testicular tissue has been performed with an endangered felid and the first successful xenotransplantation in an endangered species. Our results open important options for the preservation of biological diversity. Additional keywords: conservation, testicular tissue, threatened species, xenografting.
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effect of egg yolk cryoprotectant and various sugars on semen cryopreservation in endangered cuvier s Gazelle gazella cuvieri
Animal Reproduction Science, 2008Co-Authors: J J Garde, Montserrat Gomendio, G Espeso, A Del Olmo, A J Soler, Eduardo R S RoldanAbstract:Abstract Cryopreservation of spermatozoa from endangered species is a valuable tool for genetic management. Previous studies showed the feasibility of cryopreservation of spermatozoa from various endangered Gazelles but have also revealed difficulties with available protocols for semen freezing in Cuvier's Gazelle ( Gazella cuvieri ). Experiments were carried out to investigate the effect of (a) 5% or 20% egg yolk or 4% or 6% glycerol, and (b) addition of sugars (glucose, fructose, lactose and raffinose) on cryopreservation using a Tes-Tris-based diluent (TEST). A diluent containing 13.5% raffinose, 5% or 20% egg yolk, and 6% glycerol (REYG) was also evaluated. Semen was obtained by electroejaculation from 22 G. cuvieri males. Diluted samples were loaded into 0.25ml straws, cooled to 5°C over 1.5h (−0.16°C/min), equilibrated at that temperature for 2h, frozen in nitrogen vapours for 10min and plunged into liquid nitrogen. Subsamples were assessed for motility and acrosome integrity upon collection, after refrigeration–equilibration, after freezing and thawing, and 2h after thawing. Use of TEST with 20% egg yolk or with 4% glycerol led to worse motility preservation, whereas TEST with 5% egg yolk and 6% glycerol led to better results. Addition of fructose, lactose or raffinose to TEST resulted in similar or worse preservation of motility than inclusion of glucose. On the other hand, use of a raffinose-based medium with 20% egg yolk and 6% glycerol (REYG) afforded better preservation of motility than use of TEST. With REYG, 20% egg yolk was better than 5% egg yolk for motility preservation. Differences were noted between males in their responses to cryopreservation when using different egg yolk or glycerol concentrations. Moreover, spermatozoa from most males exhibited better cryopreservation with REYG although some were better cryopreserved in TEST. The raffinose-based diluent thus represents an improvement over previous results but more work is needed to better characterize cryopreservation conditions for future routine banking of Cuvier's Gazelle spermatozoa.
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characteristics of the semen of three endangered species of Gazelles gazella dama mhorr g dorcas neglecta and g cuvieri
Reproduction, 1998Co-Authors: Jorge Cassinello, T Abaigar, Montserrat Gomendio, Eduardo R S RoldanAbstract:Abstract As part of a captive breeding programme for three species of endangered Gazelles (Gazella dama mhorr, G. dorcas neglecta and G. cuvieri) the semen parameters for each species were characterized. The volume of ejaculated semen varied widely within species (G. dama: 565-5569 microliters; G. dorcas: 0-1454 microliters; G. cuvieri: 50-1411 microliters), as did sperm concentration (G. dama: 14-1629 x 10(6) ml-1; G. dorcas: 197-2836 x 10(6) ml-1; G. cuvieri: 228-927 x 10(6) ml-1). Sperm motility and viability were high in the three species. G. dama had a significantly lower proportion of normal spermatozoa, with a significantly higher proportion having abnormal heads and midpieces and more spermatozoa with cytoplasmic droplets. In addition, G. dama tended to have a lower proportion of spermatozoa with normal acrosomes. Sperm heads in G. dama and G. cuvieri were pear-shaped, whereas they were oval in G. dorcas. Spermatozoa from G. cuvieri were the longest. These data were also analysed in the context of three hypotheses that could explain inter-species differences in semen characteristics. Differences in testes size were due largely to differences in body size between species. However, no semen characteristic could be explained by allometric relationships. The three Gazelle species differed in the intensity of sperm competition (as measured by relative testes mass), a factor that could explain differences in the proportion of normal spermatozoa. Finally, although the three species have reached different levels of inbreeding, this factor did not explain differences in semen characteristics in the population.
Zhigang Jiang - One of the best experts on this subject based on the ideXlab platform.
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Recent Geological Events and Intrinsic Behavior Influence the Population Genetic Structure of the Chiru and Tibetan Gazelle on the Tibetan Plateau
2016Co-Authors: Fangfang Zhang, Zhigang Jiang, Yan ZengAbstract:The extent to which a species responds to environmental changes is mediated not only by extrinsic processes such as time and space, but also by species-specific ecology. The Qinghai-Tibetan Plateau uplifted approximately 3000 m and experienced at least four major glaciations during the Pleistocene epoch in the Quaternary Period. Consequently, the area experienced concurrent changes in geomorphological structure and climate. Two species, the Tibetan antelope (Pantholops hodgsonii, chiru) and Tibetan Gazelle (Procapra picticaudata), both are endemic on the Qinghai-Tibetan Plateau, where their habitats overlap, but have different migratory behaviors: the chiru is inclined to have female-biased dispersal with a breeding migration during the calving season; in contrast, Tibetan Gazelles are year-round residents and never migrate distantly. By using coalescence methods we compared mitochondrial control region DNA sequences and variation at nine microsatellite loci in these two species. Coalescent simulations indicate that the chiru and Tibetan Gazelle do not share concordant patterns in their genealogies. The non-migratory Tibetan Gazelle, that is more vulnerable to the impact of drastic geographic changes such as the elevation of the plateau, glaciations and so on, appears to have a strong population genetic structure with complicated demographic history. Specifically, the Tibetan Gazelle population appears to have experienced isolation and divergence with population fluctuations since the Middle Pleistocene (0.781 Ma). However, it showed continued decline since the Upper Pleistocene (0.126 Ma), which may be attributed to the irreversible impact o
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isolation and characterization of cross amplification microsatellite panels for species of procapra bovidae antilopinae
International Journal of Molecular Sciences, 2012Co-Authors: Jing Chen, Ji Yang, Zhenhua Luo, Songhua Tang, Bingwan Liu, Zhigang JiangAbstract:The three Procapra species, Tibetan Gazelle (P. picticaudata), Mongolian Gazelle (P. gutturosa) and Przewalski’s Gazelle (P. przewalskii) are endemic to Asia. Several intraspecific genetic issues have been studied with species-specific microsatellite loci in these Asian Gazelles. However, cross-species microsatellite panels are absent, which inhibits comparative conservation and evolutionary studies of the Procapra. In this study, we isolated 20 cross-species microsatellite loci for Procapra from both related species and the genomic library of P. przewalskii. Fifty-three samples of the three Gazelles were used to characterize the markers. Allele numbers ranged from three to 20, with a mean of 7.93 per locus. Observed heterozygosity (HO) averaged 0.680 and expected heterozygosity (HE) 0.767. The mean polymorphic information content (PIC) was 0.757 for P. picticaudata, 0.803 for P. gutturosa and 0.590 for P. przewalskii. Nine loci were significantly deviated from Hardy-Weinberg (H-W) equilibrium in the three species. Significant linkage disequilibrium was detected in four pairs of loci in P. przewalskii, five pairs in P. gutturosa and 51 pairs in P. picticaudata. Considering the abundance of published loci and their high success rates of cross-amplification, testing and utilization of loci from related species is efficient for wild species of Bovidae. The cross-species microsatellite loci we developed will facilitate further interspecies genetic studies in Procapra.
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climate change hastens the conservation urgency of an endangered ungulate
PLOS ONE, 2011Co-Authors: Zhigang JiangAbstract:Global climate change appears to be one of the main threats to biodiversity in the near future and is already affecting the distribution of many species. Currently threatened species are a special concern while the extent to which they are sensitive to climate change remains uncertain. Przewalski's Gazelle (Procapra przewalskii) is classified as endangered and a conservation focus on the Qinghai-Tibetan Plateau. Using measures of species range shift, we explored how the distribution of Przewalski's Gazelle may be impacted by projected climate change based on a maximum entropy approach. We also evaluated the uncertainty in the projections of the risks arising from climate change. Modeling predicted the Przewalski's Gazelle would be sensitive to future climate change. As the time horizon increased, the strength of effects from climate change increased. Even assuming unlimited dispersal capacity of Gazelles, a moderate decrease to complete loss of range was projected by 2080 under different thresholds for transforming the probability prediction to presence/absence data. Current localities of Gazelles will undergo a decrease in their occurrence probability. Projections of the impacts of climate change were significantly affected by thresholds and general circulation models. This study suggests climate change clearly poses a severe threat and increases the extinction risk to Przewalski's Gazelle. Our findings 1) confirm that endangered endemic species is highly vulnerable to climate change and 2) highlight the fact that forecasting impacts of climate change needs an assessment of the uncertainty. It is extremely important that conservation strategies consider the predicted geographical shifts and be planned with full knowledge of the reliability of projected impacts of climate change.
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effect of anthropogenic landscape features on population genetic differentiation of przewalski s Gazelle main role of human settlement
PLOS ONE, 2011Co-Authors: Ji Yang, Zhigang Jiang, Yan Zeng, Mardan Turghan, Hongxia FangAbstract:Anthropogenic landscapes influence evolutionary processes such as population genetic differentiation, however, not every type of landscape features exert the same effect on a species, hence it is necessary to estimate their relative effect for species management and conservation. Przewalski's Gazelle (Procapra przewalskii), which inhabits a human-altered area on Qinghai-Tibet Plateau, is one of the most endangered antelope species in the world. Here, we report a landscape genetic study on Przewalski's Gazelle. We used skin and fecal samples of 169 wild Gazelles collected from nine populations and thirteen microsatellite markers to assess the genetic effect of anthropogenic landscape features on this species. For comparison, the genetic effect of geographical distance and topography were also evaluated. We found significant genetic differentiation, six genetic groups and restricted dispersal pattern in Przewalski's Gazelle. Topography, human settlement and road appear to be responsible for observed genetic differentiation as they were significantly correlated with both genetic distance measures [FST/(1−FST) and F′ST/(1−F′ST)] in Mantel tests. IBD (isolation by distance) was also inferred as a significant factor in Mantel tests when genetic distance was measured as FST/(1−FST). However, using partial Mantel tests, AICc calculations, causal modeling and AMOVA analysis, we found that human settlement was the main factor shaping current genetic differentiation among those tested. Altogether, our results reveal the relative influence of geographical distance, topography and three anthropogenic landscape-type on population genetic differentiation of Przewalski's Gazelle and provide useful information for conservation measures on this endangered species.
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effects of highway traffic on diurnal activity of the critically endangered przewalski s Gazelle
Wildlife Research, 2009Co-Authors: Zhigang Jiang, Zuojian Feng, Xiaobo Yang, Ji Yang, Liwei ChenAbstract:Highway traffic is considered to be one of the factors that influence survival of wildlife. Przewalski’s Gazelle is a critically endangered species that lives in the Qinghai Lake watershed of western China. To learn the impacts of traffic on activity patterns of Przewalski’s Gazelle, we investigated the relationship between traffic flow and diurnal behaviours of the Gazelle on the eastern shore of Qinghai Lake, where a highway was built in 2002. During the summers of 2005 and 2006, we collected traffic data on the highway and observed the activity of the Przewalski’s Gazelle population in the area. The results of statistical analysis showed the following: (1) frequency of behaviours such as standing, locomotion, foraging and resting differed among the 15 1-h sampling periods (daytime); (2) numbers of total vehicles, heavy vehicles and light vehicles were significantly different among the daytime hours; (3) there was a positive correlation between the frequency of resting of the Gazelles and the number of passing vehicles, and a negative correlation between the frequencies of foraging and alert responses and the number of passing vehicles; (4) by comparing our results with those of a previous study on the Gazelles at this site, before the construction of the highway, we found that the diurnal rhythms of foraging, standing and resting have changed markedly (e.g. the three peaks of foraging at 1300, 1600 and 1800 hours in 1996 changed to two peaks of foraging at 0600 and 2000 hours). Our results suggest that the highway traffic may have caused a change in diurnal activity of Przewalski’s Gazelle, with the animals tending to keep away from the highway when the traffic flow is high. We suggest traffic-control measures to reduce disturbance to, and thus enhance conservation of, this highly threatened species.
Samer Alasaad - One of the best experts on this subject based on the ideXlab platform.
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sarcoptic mange and cheetah conservation in masai mara kenya epidemiological study in a wildlife livestock system
Parasitology, 2012Co-Authors: Francis Gakuya, Jackson Ombui, Ndichu Maingi, Gerald Muchemi, Ramón C. Soriguer, W O Ogara, Samer AlasaadAbstract:: The sanitary control of threatened wild animals is of pivotal interest for their conservation. This task, however, is highly complex in wildlife/livestock systems. In this paper we report findings from a 2-year cross-sectional study of the epidemiology and attempted control of a Sarcoptes mite infestation in the threatened cheetah population in Masai Mara (Kenya), and discuss its interaction with sympatric wild (lion, wildebeest and Thomson's Gazelle) and domestic (dog, cattle and sheep) animals. Sarcoptes scabiei was isolated from cheetahs, Thomson's Gazelles, wildebeests, lions, cattle, goats and dogs; Psoroptes ovis, on the other hand, was only isolated from sheep. The prevalence study revealed 12·77% infection rates in cheetahs, 4·7% in dogs, 0·8% in Thomson's Gazelles, 0·8% in sheep, 0·09% in cattle, and 0·09% in goats, while it opportunistically affected lions and wildebeest. Our study revealed that prevalence of Sarcoptes mite in cheetah population was not associated with the studied geographical blocks, animal sex or the presence of affected domestic animals. Cheetah infection with S. scabiei was associated with the climatic conditions (dry more than wet season) and the balancing between the total number of Thomson's Gazelles and the prevalence of infected individuals. Apparently the high prevalence of mangy Gazelles has a negative effect on cheetah; this negative effect was reduced when the number of healthy Gazelles was increased. Treatment with injectable ivermectin of the clinically affected wild and domestic animals during the first year of this study was associated with much lower incidence of sarcoptic mange during the second year.
