Characterizing the Spread and Consequences of Mycoplasma ovipneumoniae on Bighorn Sheep (Ovis canadensis) in the Northern Basin and Range Ecosystem

North American bighorn sheep (Ovis canadensis) have experienced significant declines and population extirpations due to novel pathogens such as Mycoplasma ovipneumoniae. This disease continues to limit the population restoration of bighorn sheep. Therefore, understanding the demographic consequences of pathogen presence and the risk of contact between bighorn populations and potential sources of pathogens is vital to managing bighorn sheep populations effectively, especially for pathogens that cause respiratory pneumonia. My dissertation focuses on characterizing the spread and consequences of respiratory disease caused by M. ovipneumoniae in southeastern Oregon and northern Nevada. I carried out four interdisciplinary studies involving extensive fieldwork, epidemiological, genetic, geospatial, and statistical methodologies to determine factors influencing bighorn sheep demography and spatial ecology. My research relied in part on data provided by two state wildlife management agencies, Oregon Department of Fish and Wildlife (ODFW) and Nevada Department of Wildlife (NDOW), that captured adult female and male bighorn sheep, fitted them with GPS collars that generated and remotely transmitted remotely location data, and sampled them to generate diagnostics and genetic testing. I collected additional observational and non-invasive data within the system. In Chapter 2, I investigated the effect of M. ovipneumoniae on juvenile survival within our study system. I used observational data of juveniles and PCR-testing of juveniles that were found dead to analyze juvenile survival relative to M. ovipneumoniae presence, population genetic diversity, and forage characteristics. That study showed that the presence of M. ovipneumoniae can cause extremely low juvenile survival but found little influence of population genetic diversity or nutritional effects on juvenile survival. In addition, the study showed that even very low prevalence of M. ovipneumoniae in adults can have harmful effects on juveniles and that targeted removals of infected adults should be considered. In Chapter 3, I investigated the effect of exposure and infection of M. ovipneumoniae and other factors on GPS-collared adults using known-fate models. M. ovipneumoniae-exposed adults had lower survival than unexposed individuals, and I found evidence, albeit weaker, that adult survival was lower for males and in populations where genetic diversity was lower. The low prevalence of M. ovipneumoniae-exposed individuals suggests that chronic shedders and birth pulses maintain the pathogen. While targeted removals have been used as an effective tool to manage juvenile survival in bighorn sheep, these results indicate adults may benefit from this action too. I also recommended that management increase genetic diversity of populations that have suffered from sequential founder effects, although such action would have to be weighed carefully against the risk of increased disease exposure. For Chapter 4, I used GPS collar data to investigate space and habitat use patterns – key features of host behavior that impact pathogen exposure and transmission, as well as gene flow and metapopulation function. I assessed utilization distributions, site fidelity, social affinity, and resource selection functions separately for male and female bighorn. Although resource selection by both sexes was quite similar within the same seasons, female bighorn sheep exhibited extremely high site fidelity and social affinity, much higher than observed in other systems. Site fidelity and social affinity of male bighorn sheep were significantly lower, with numerous interpopulation movements. Our findings suggest that male bighorn sheep are responsible for disease transmission between the populations and maintain gene flow within the system. Still, females' high site fidelity and social affinity have resulted in the low potential for colonization of unused habitat, and I identified several areas of potential habitat that are unused by females but could increase distribution or enhance connectivity if occupied. In Chapter 5, I used the methodology of O’Brien et al. (2014) to estimate the risk of contact for each study population with potential sources of M. ovipneumoniae, including domestic sheep grazing allotments, other bighorn sheep populations, or potential sources of domestic sheep and goats. I found that all study populations had some probability of contact with other possible sources of infection risk, although those sources did not include known domestic sheep grazing allotments. This study therefore provides a tool to prioritize outreach to private landowners or management of disease within affected bighorn populations that may pose risk to other populations. This study highlights the adverse effects of M. ovipneumoniae persistence on bighorn sheep population recovery and the complications of managing metapopulation connectivity in a disease-impacted system. Management options to control pathogen spread must balance connectivity's negative and positive consequences. The management agencies responsible for these bighorn populations have initiated test and remove programs to deal with asymptomatic carriers within the system. However, our findings suggest further actions may be needed to improve genetic diversity and promote habitat colonization while considering disease risks associated with these actions. Hopefully, the data presented here inform efforts that help mitigate further exposure to novel strains of M. ovipneumoniae while maintaining necessary metapopulation functions

Bovine tuberculosis disturbs parasite functional trait composition in African buffalo

Novel parasites can have wide-ranging impacts, not only on host populations, but also on the resident parasite community. Historically, impacts of novel parasites have been assessed by examining pairwise interactions between parasite species. However, parasite communities are complex networks of interacting species. Here we used multivariate taxonomic and trait-based approaches to determine how parasite community composition changed when African buffalo (Syncerus caffer) acquired an emerging disease, bovine tuberculosis (BTB). Both taxonomic and functional parasite richness increased significantly in animals that acquired BTB than in those that did not. Thus, the presence of BTB seems to catalyze extraordinary shifts in community composition. There were no differences in overall parasite taxonomic composition between infected and uninfected individuals, however. The trait-based analysis revealed an increase in direct-transmitted, quickly replicating parasites following BTB infection. This study demonstrates that trait-based approaches provide insight into parasite community dynamics in the context of emerging infections

Context-dependent costs and benefits of tuberculosis resistance traits in a wild mammalian host

Disease acts as a powerful driver of evolution in natural host populations, yet individuals in a population often vary in their susceptibility to infection. Energetic trade-offs between immune and reproductive investment lead to the evolution of distinct life history strategies, driven by the relative fitness costs and benefits of resisting infection. However, examples quantifying the cost of resistance outside of the laboratory are rare. Here, we observe two distinct forms of resistance to bovine tuberculosis (bTB), an important zoonotic pathogen, in a free-ranging African buffalo (Syncerus caffer) population. We characterize these phenotypes as “infection resistance,” in which hosts delay or prevent infection, and “proliferation resistance,” in which the host limits the spread of lesions caused by the pathogen after infection has occurred. We found weak evidence that infection resistance to bTB may be heritable in this buffalo population (h2 = 0.10) and comes at the cost of reduced body condition and marginally reduced survival once infected, but also associates with an overall higher reproductive rate. Infection-resistant animals thus appear to follow a “fast” pace-of-life syndrome, in that they reproduce more quickly but die upon infection. In contrast, proliferation resistance had no apparent costs and was associated with measures of positive host health—such as having a higher body condition and reproductive rate. This study quantifies striking phenotypic variation in pathogen resistance and provides evidence for a link between life history variation and a disease resistance trait in a wild mammalian host population

Observation of an Excited Bc+ State

Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+γ decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date

Measurement of the inelastic pp cross-section at a centre-of-mass energy of 13TeV

The cross-section for inelastic proton-proton collisions at a centre-of-mass energy of 13TeV is measured with the LHCb detector. The fiducial cross-section for inelastic interactions producing at least one prompt long-lived charged particle with momentum p > 2 GeV/c in the pseudorapidity range 2 < η < 5 is determined to be ϭ acc = 62:2 ± 0:2 ± 2:5mb. The first uncertainty is the intrinsic systematic uncertainty of the measurement, the second is due to the uncertainty on the integrated luminosity. The statistical uncertainty is negligible. Extrapolation to full phase space yields the total inelastic proton-proton cross-section ϭ inel = 75:4 ± 3:0 ± 4:5mb, where the first uncertainty is experimental and the second due to the extrapolation. An updated value of the inelastic cross-section at a centre-of-mass energy of 7TeV is also reported

Updated Determination of D⁰–D¯⁰Mixing and CP Violation Parameters with D⁰→K⁺π⁻ Decays

We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D⁰→K⁺π⁻ to D⁰→K⁻π⁺ rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of 5.0  fb⁻¹ recorded by the LHCb experiment from 2011 through 2016. Assuming charge-parity (CP) symmetry, the mixing parameters are determined to be x′²=(3.9±2.7)×10⁻⁵, y′=(5.28±0.52)×10⁻³, and R[subscript D]=(3.454±0.031)×10⁻³. Without this assumption, the measurement is performed separately for D⁰ and D[over ¯]⁰ mesons, yielding a direct CP-violating asymmetry A[subscript D]=(-0.1±9.1)×10⁻³, and magnitude of the ratio of mixing parameters 1.00<|q/p|<1.35 at the 68.3% confidence level. All results include statistical and systematic uncertainties and improve significantly upon previous single-measurement determinations. No evidence for CP violation in charm mixing is observed

Observation of D⁰ Meson Decays to Π⁺π⁻μ⁺μ⁻ and K⁺K⁻μ⁺μ⁻ Final States

The first observation of the D⁰→π⁺π⁻μ⁺μ⁻ and D⁰→K⁺K⁻μ⁺μ⁻ decays is reported using a sample of proton-proton collisions collected by LHCb at a center-of-mass energy of 8 TeV, and corresponding to 2  fb⁻¹ of integrated luminosity. The corresponding branching fractions are measured using as normalization the decay D⁰→K⁻π⁺[μ⁺μ⁻][subscript ρ⁰/ω], where the two muons are consistent with coming from the decay of a ρ⁰ or ω meson. The results are B(D⁰→π⁺π⁻μ⁺μ⁻)=(9.64±0.48±0.51±0.97)×10⁻⁷ and B(D⁰→K⁺K⁻μ⁺μ⁻)=(1.54±0.27±0.09±0.16)×10⁻⁷, where the uncertainties are statistical, systematic, and due to the limited knowledge of the normalization branching fraction. The dependence of the branching fraction on the dimuon mass is also investigated

Observation of the Λb0 → χc1 (3872) pK− decay

No abstract available

Measurement of CP -violating and mixing-induced observables in Bs0→ϕγ decays

A time-dependent analysis of the B 0 s → ϕ γ decay rate is performed to determine the C P -violating observables S ϕ γ and C ϕ γ and the mixing-induced observable A Δ ϕ γ . The measurement is based on a sample of p p collision data recorded with the LHCb detector, corresponding to an integrated luminosity of 3     fb − 1 at center-of-mass energies of 7 and 8 TeV. The measured values are S ϕ γ = 0.43 ± 0.30 ± 0.11 , C ϕ γ = 0.11 ± 0.29 ± 0.11 , and A Δ ϕ γ = − 0.67 + 0.37 − 0.41 ± 0.17 , where the first uncertainty is statistical and the second systematic. This is the first measurement of the observables S and C in radiative B 0 s decays. The results are consistent with the standard model predictions