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Disease and Predation: Sorting out Causes of a Bighorn Sheep (Ovis canadensis) Decline  [PDF]
Joshua B. Smith, Jonathan A. Jenks, Troy W. Grovenburg, Robert W. Klaver
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0088271
Abstract: Estimating survival and documenting causes and timing of mortality events in neonate bighorn sheep (Ovis canadensis) improves understanding of population ecology and factors influencing recruitment. During 2010–2012, we captured and radiocollared 74 neonates in the Black Hills, South Dakota, of which 95% (70) died before 52 weeks of age. Pneumonia (36%) was the leading cause of mortality followed by predation (30%). We used known fate analysis in Program MARK to estimate weekly survival rates and investigate the influence of intrinsic variables on 52-week survival. Model {S1 wk, 2–8 wks, >8 wks} had the lowest AICc (Akaike’s Information Criterion corrected for small sample size) value, indicating that age (3-stage age-interval: 1 week, 2–8 weeks, and >8 weeks) best explained survival. Weekly survival estimates for 1 week, 2–8 weeks, and >8 weeks were 0.81 (95% CI = 0.70–0.88), 0.86 (95% CI = 0.81–0.90), and 0.94 (95% CI = 0.91–0.96), respectively. Overall probability of surviving 52 weeks was 0.02 (95% CI = 0.01–0.07). Of 70 documented mortalities, 21% occurred during the first week, 55% during weeks 2–8, and 23% occurred >8 weeks of age. We found pneumonia and predation were temporally heterogeneous with lambs most susceptible to predation during the first 2–3 weeks of life, while the greatest risk from pneumonia occurred from weeks 4–8. Our results indicated pneumonia was the major factor limiting recruitment followed by predation. Mortality from predation may have been partly compensatory to pneumonia and its effects were less pronounced as alternative prey became available. Given the high rates of pneumonia-caused mortality we observed, and the apparent lack of pneumonia-causing pathogens in bighorn populations in the western Black Hills, management activities should be geared towards eliminating contact between diseased and healthy populations.
A Review of Hypothesized Determinants Associated with Bighorn Sheep (Ovis canadensis) Die-Offs  [PDF]
David S. Miller,Eric Hoberg,Glen Weiser,Keith Aune,Mark Atkinson,Cleon Kimberling
Veterinary Medicine International , 2012, DOI: 10.1155/2012/796527
Abstract: Multiple determinants have been hypothesized to cause or favor disease outbreaks among free-ranging bighorn sheep (Ovis canadensis) populations. This paper considered direct and indirect causes of mortality, as well as potential interactions among proposed environmental, host, and agent determinants of disease. A clear, invariant relationship between a single agent and field outbreaks has not yet been documented, in part due to methodological limitations and practical challenges associated with developing rigorous study designs. Therefore, although there is a need to develop predictive models for outbreaks and validated mitigation strategies, uncertainty remains as to whether outbreaks are due to endemic or recently introduced agents. Consequently, absence of established and universal explanations for outbreaks contributes to conflict among wildlife and livestock stakeholders over land use and management practices. This example illustrates the challenge of developing comprehensive models for understanding and managing wildlife diseases in complex biological and sociological environments. 1. Introduction Effective management and conservation of wildlife populations can be undermined by multiple causes. These include decreased and altered habitat and other direct anthropogenic effects, climate change, competition and predation from nonnative wildlife and domestic species, demographic challenges associated with small populations, multiple, incompatible management objectives for sympatric species or their habitat, and exposure to native and exotic infectious agents [1–4]. The consequences and interactions of these variables are difficult to understand and predict, and may vary by circumstances. This uncertainty, particularly when it occurs in complex sociological environments where stakeholders have differing values and objectives, presents substantial challenges for decision makers. In such uncertain environments, the absence of data and differing values can result in polarized debate among stakeholders. It can also serve as an impediment to the acquisition of data that would contribute to effective management. Respiratory disease outbreaks in bighorn sheep (Ovis canadensis) illustrate the challenge of identifying and managing disease in valued wildlife populations, where stakeholder perceptions and values clash [5]. Bighorn sheep are highly valued for recreational, ecological, philosophical, spiritual, and other reasons [6]. Bighorns have experienced a population decline of two orders of magnitude subsequent to 19th century settlement of western North
Habitat use by desert bighorn sheep in sonora, México
Tarango, L. A.,Krausman, R.,Valdez, R.
Pirineos : Revista de Ecología de Monta?a , 2002,
Abstract: The use of habitat components by desert bighorn sheep (Ovis canadensis) was examined to explain sexual segregation of sheep in Sierra el Viejo, Sonora, Mexico. We evaluated 265 plots used by bighorns and 278 random plots from April 1997 to December 1998. Groups of segregated males and females preferred the elephant tree (Bursera microphylla)-salvia (Salvia mellifera)-limber bush (Jatropha cuneata) association (ESL) and avoided the foothill palo verde (Cercidium microphyllum)-desert ironwood (Olneya tesota) association (FDD. Segregated females selected the ocotillo (Fouquieria splendens)-desert agave (Agave spp.yhop bush (Dodonoea viscosa) (OAH) vegetation association, formed larger groups, were closer to escape terrain, and occupied more rugged areas during autumn and spring than males. Segregated females selected areas that provided more opportunities to evade predation than did males. [fr] Nous avons étudié les différents composants de l'utilisation de l'habitat par le mouflon américain (Ovis canadensis) afin d'expliquer sa ségrégation sexuelle dans la Sierra el Viejo, à Sonora, Mexique. D'avril 1997 à Décembre 1998, on a évalué 265 parcelles utilisées par les mouflons et 278 parcelles au hasard. Différents groupes séparés de males et femelles préféraient l'association (ESL) formée par l'arbre Bursera microphylla, la sauge (Salvia mellifera) et l'arbuste Jatropa cuneata et ils évitaient l'association (FDD composée du Cercidium microphyllum et /'Olneya tesota. Les groupes de femelles sélectionaient l'association végétale (OAH) de Fouquieria splendens. Agave spp. et l'arbuste Dodonoea viscosa; et par rapport aux males, elles formaient de plus grands groupes, étaient plus proches de la zone de fuite et elles occupaient des terrains plus accidentés en automne et au printemps. Les groupes de femelles, plus que les males, cherchaient des zones avec moins de risque de prédation. [es] Se examinó el uso del hábitat del muflón americano Ovis canadensis para explicar su segregación sexual en Sierra el Viejo, Sonora, Méjico. Se establecieron 265 parcelas usadas por el muflón y 278 tomadas al azar, desde abril de 1997 hasta diciembre de 1998. Los grupos segregados de machos y hembras prefirieron la asociación (ESL) torote blanco (Bursera microphyllaj-sn/z^m (Salvia mellifera)- sangreado (Jatropha cuneata) y evitaron la asociación (FDI) palo verde (Cercidium microphyllum)-palo fierro (Olneya tesota). Los grupos de hembras seleccionaron la asociación ocotillo (Fouquieria splendens)-ágave (Agave spp.)- chirca (Dodonaea viscosa) (OAH); formaron grandes grupos, estando
Consumption of an adult Puma yagouaroundi (Felidae) by the snake Boa constrictor (Boidae) in Central Mexico
Monroy-Vilchis, Octavio;Sánchez, óscar;Urios, Vicente;
Revista mexicana de biodiversidad , 2011,
Abstract: few felids have been recorded as being preyed upon by the boa constrictor snake (boa constrictor). documentation of predation on felids by reptiles is scarce, and natural predators of the adult jaguarundi (puma yagouaroundi) are poorly known. here, we report for the first time an adult male jaguarundi being eaten by the snake boa constrictor (of 273 cm snout-to-vent length) at the sierra nanchititla natural reserve, estado de méxico.
Local Extinction and Unintentional Rewilding of Bighorn Sheep (Ovis canadensis) on a Desert Island  [PDF]
Benjamin T. Wilder, Julio L. Betancourt, Clinton W. Epps, Rachel S. Crowhurst, Jim I. Mead, Exequiel Ezcurra
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0091358
Abstract: Bighorn sheep (Ovis canadensis) were not known to live on Tiburón Island, the largest island in the Gulf of California and Mexico, prior to the surprisingly successful introduction of 20 individuals as a conservation measure in 1975. Today, a stable island population of ~500 sheep supports limited big game hunting and restocking of depleted areas on the Mexican mainland. We discovered fossil dung morphologically similar to that of bighorn sheep in a dung mat deposit from Mojet Cave, in the mountains of Tiburón Island. To determine the origin of this cave deposit we compared pellet shape to fecal pellets of other large mammals, and extracted DNA to sequence mitochondrial DNA fragments at the 12S ribosomal RNA and control regions. The fossil dung was 14C-dated to 1476–1632 calendar years before present and was confirmed as bighorn sheep by morphological and ancient DNA (aDNA) analysis. 12S sequences closely or exactly matched known bighorn sheep sequences; control region sequences exactly matched a haplotype described in desert bighorn sheep populations in southwest Arizona and southern California and showed subtle differentiation from the extant Tiburón population. Native desert bighorn sheep previously colonized this land-bridge island, most likely during the Pleistocene, when lower sea levels connected Tiburón to the mainland. They were extirpated sometime in the last ~1500 years, probably due to inherent dynamics of isolated populations, prolonged drought, and (or) human overkill. The reintroduced population is vulnerable to similar extinction risks. The discovery presented here refutes conventional wisdom that bighorn sheep are not native to Tiburón Island, and establishes its recent introduction as an example of unintentional rewilding, defined here as the introduction of a species without knowledge that it was once native and has since gone locally extinct.
Surgical correction of degenerative lumbosacral stenosis in a puma (Puma concolor araucana)
Verdugo,C; Gómez,M; Alvarado-Rybak,M; Bustamante,H; Cardona,L; Mieres,M;
Archivos de medicina veterinaria , 2011, DOI: 10.4067/S0301-732X2011000300014
Abstract: a 12-year-old adult, intact male puma (puma concolor araucana) was evaluated because of abnormal hind limb gait and paresis. neurological examination revealed a progressive paraparesis, bilateral pelvic limb proprioceptive deficit and tail paralysis. survey radiographs and computed tomography (ct) were taken at the lumbosacral region in order to determine possible causes. ct study confirmed a stenotic vertebral canal at the l7/s1 level. a dorsal laminectomy was performed in order to decompress the affected area. histopathologic examination of the harvested material revealed inflammation and hypertrophy of the ligamentum flavum. two weeks after the surgery, the puma showed progressive neurologic improvement and normal ambulation.
Conservación del puma en el Parque Nacional Sajama (Bolivia): estado poblacional y alternativas de manejo
Gallardo,Giovana; Nu?ez,Angela; Pacheco,Luis F.; Ruiz-García,Manuel;
Mastozoolog?-a neotropical , 2009,
Abstract: livestock predation by puma in parque nacional sajama (pns) has generated a strong conflict between the economic interests of local communities and the conservation of this species. the objective of this paper is to provide information about the status of the puma population within the pns and present possible options for diminishing the conflict. five specimens of pumas were identified through be dna microsatelites analysis extracted from fecal samples, and according to density estimates the maximum population expected for pns should be of 10 adult pumas. pumas of pns showed a high genetic diversity (h=0.94) and a relatively high gene flow. for this reason, the hunting of pumas within the pns cannot be considered a solution of the conflict. we suggest the following alternatives: 1) to improve several aspects of livestock management; 2) to test the use of conditioning taste aversion practices; 3) to explore special markets for meat and fiber of domestic animals of the pns (friendly with predators); 4) selective eco-tourism; 5) economic compensation by means of projects explicitly linked to conservation. appropriate actions in order to resolve this conflict should be urgently taken, before the local stockbreeders take their own actions that will probably affect negatively the puma populations.
Regulation of PUMA induced by mechanical stress in rat cardiomyocytes  [cached]
Cheng Wen-Pin,Wu Gong-Jhe,Wang Bao-Wei,Shyu Kou-Gi
Journal of Biomedical Science , 2012, DOI: 10.1186/1423-0127-19-72
Abstract: Background PUMA (p53-up-regulated modulator of apoptosis), an apoptosis regulated gene, increased during endoplasmic reticulum stress. However, the expression of PUMA in cardiomyocytes under mechanical stress is little known. We aimed to investigate the regulation mechanism of PUMA expression and apoptosis induced by mechanical stress in cardiomyocytes. Methods Aorta-caval (AV) shunt was performed in adult Wistar rats to induce volume overload. Rat neonatal cardiomyocytes were stretched by vacuum to 20% of maximum elongation at 60 cycles/min. Results PUMA protein and mRNA were up-regulated in the shunt group as compared with sham group. The increased PUMA protein expression and apoptosis induced by shunt was reversed by treatment with atorvastatin at 30 mg/kg/ day orally for 7 days. TUNEL assay showed that treatment with atorvastatin inhibited the apoptosis induced by volume overload. Cyclic stretch significantly enhanced PUMA protein and gene expression. Addition of c-jun N-terminal kinase (JNK) inhibitor SP600125, JNK small interfering RNA (siRNA) and interferon-γ (INF-γ) antibody 30 min before stretch reduced the induction of PUMA protein. Gel shift assay demonstrated that stretch increased the DNA binding activity of interferon regulatory factor-1. Stretch increased, while PUMA-Mut plasmid, SP600125 and INF-γ antibody abolished the PUMA promoter activity induced by stretch. PUMA mediated apoptosis induced by stretch was reversed by PUMA siRNA and atorvastatin. Conclusions Mechanical stress enhanced apoptosis and PUMA expression in cardiomyocytes. Treatment with atorvastatin reversed both PUMA expression and apoptosis induced by mechanical stress in cardiomyocytes.
Shared Bacterial and Viral Respiratory Agents in Bighorn Sheep (Ovis canadensis), Domestic Sheep (Ovis aries), and Goats (Capra hircus) in Montana  [PDF]
David S. Miller,Glen C. Weiser,Keith Aune,Brent Roeder,Mark Atkinson,Neil Anderson,Thomas J. Roffe,Kim A. Keating,Phillip L. Chapman,Cleon Kimberling,Jack Rhyan,P. Ryan Clarke
Veterinary Medicine International , 2011, DOI: 10.4061/2011/162520
Abstract: Transmission of infectious agents from livestock reservoirs has been hypothesized to cause respiratory disease outbreaks in bighorn sheep (Ovis canadensis), and land management policies intended to limit this transmission have proven controversial. This cross-sectional study compares the infectious agents present in multiple populations of bighorn sheep near to and distant from their interface with domestic sheep (O. aries) and domestic goat (Capra hircus) and provides critical baseline information needed for interpretations of cross-species transmission risks. Bighorn sheep and livestock shared exposure to Pasteurellaceae, viral, and endoparasite agents. In contrast, although the impact is uncertain, Mycoplasma sp. was isolated from livestock but not bighorn sheep. These results may be the result of historic cross-species transmission of agents that has resulted in a mosaic of endemic and exotic agents. Future work using longitudinal and multiple population comparisons is needed to rigorously establish the risk of outbreaks from cross-species transmission of infectious agents. 1. Introduction Bighorn sheep (Ovis canadensis) experienced substantial decreases in population numbers and range in the 19th and the early 20th centuries, and subsequent recovery efforts have often been limited by large-scale die-offs [1–3]. These initial population declines were associated with settlement of western North America and were attributed to unregulated hunting, competition for forage with domestic sheep (O. aries) and other livestock, and disruption of historic bighorn sheep migration patterns due to development. Clinical disease was apparently unimportant or was underreported in these early declines, though die-offs of bighorn sheep associated with sheep scab (Psoroptes sp.) were reported following settlement [4, 5]. Bighorn sheep die-offs associated with pneumonia were reported in the 1920s and 1930s [6–10]. These early reports and subsequent work largely focused on lungworm (Protostrongylus sp.) as the primary infectious agent, although the involvement of Pasteurella sp., Corynebacterium pyogenes (currently Arcanobacterium pyogenes), and other host and environmental determinants were also noted as potential causes of respiratory disease. Subsequently, inconsistent association of lungworm with respiratory disease in bighorn sheep, as well as further evidence for Pasteurella sp. as the cause of pneumonia, led to a focus on pasteurellosis as a cause of respiratory disease outbreaks [11–14]. This research included evidence that Pasteurella sp. strains from clinically
Genetic linkage map of a wild genome: genomic structure, recombination and sexual dimorphism in bighorn sheep
Jocelyn Poissant, John T Hogg, Corey S Davis, Joshua M Miller, Jillian F Maddox, David W Coltman
BMC Genomics , 2010, DOI: 10.1186/1471-2164-11-524
Abstract: Bighorn sheep population-specific maps differed slightly in contiguity but were otherwise very similar in terms of genomic structure and recombination rates. The joint analysis of the two pedigrees resulted in a highly contiguous map composed of 247 microsatellite markers distributed along all 26 autosomes and the X chromosome. The map is estimated to cover about 84% of the bighorn sheep genome and contains 240 unique positions spanning a sex-averaged distance of 3051 cM with an average inter-marker distance of 14.3 cM. Marker synteny, order, sex-averaged interval lengths and sex-averaged total map lengths were all very similar between sheep species. However, in contrast to domestic sheep, but consistent with the usual pattern for a placental mammal, recombination rates in bighorn sheep were significantly greater in females than in males (~12% difference), resulting in an autosomal female map of 3166 cM and an autosomal male map of 2831 cM. Despite differing genome-wide patterns of heterochiasmy between the sheep species, sexual dimorphism in recombination rates was correlated between orthologous intervals.We have developed a first-generation bighorn sheep linkage map that will facilitate future studies of the genetic architecture of trait variation in this species. While domestication has been hypothesized to be responsible for the elevated mean recombination rate observed in domestic sheep, our results suggest that it is a characteristic of Ovis species. However, domestication may have played a role in altering patterns of heterochiasmy. Finally, we found that interval-specific patterns of sexual dimorphism were preserved among closely related Ovis species, possibly due to the conserved position of these intervals relative to the centromeres and telomeres. This study exemplifies how transferring genomic resources from domesticated species to close wild relative can benefit evolutionary ecologists while providing insights into the evolution of genomic structure and
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