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Mycobacterium bovis infection, which is a prominent cause of bovine tuberculosis, has been confirmed by mycobacterial culture in African rhinoceros species in Kruger National Park (KNP), South Africa. In this population-based study of the epidemiology of M. bovis in 437 African rhinoceros (Diceros bicornis, Ceratotherium simum), we report an estimated prevalence of 15.4% (95% CI: 10.4 to 21.0%), based on results from mycobacterial culture and an antigen-specific interferon gamma release assay from animals sampled between 2016 and 2020. A significant spatial cluster of cases was detected near the southwestern park border, although infection was widely distributed. Multivariable logistic regression models, including demographic and spatiotemporal variables, showed a significant, increasing probability of M. bovis infection in white rhinoceros based on increased numbers of African buffalo (Syncerus caffer) herds in the vicinity of the rhinoceros sampling location. Since African buffaloes are important maintenance hosts for M. bovis in KNP, spillover of infection from these hosts to white rhinoceros sharing the environment is suspected. There was also a significantly higher proportion of M. bovis infection in black rhinoceros in the early years of the study (2016-2018) than in 2019 and 2020, which coincided with periods of intense drought, although other temporal factors could be implicated. Species of rhinoceros, age, and sex were not identified as risk factors for M. bovis infection. These study findings provide a foundation for further epidemiological investigation of M. bovis, a multihost pathogen, in a complex ecosystem that includes susceptible species that are threatened and endangered. [ABSTRACT FROM AUTHOR]

Vascular cognitive impairment (VCI), including vascular dementia, is the second most common dementia after Alzheimer's disease. Despite its prevalence, the genetic etiology of sporadic VCI is largely unknown. We conducted a systematic review of all published genetic association studies of forms of sporadic VCI prior to 6 July 2012. An initial pool of 229 gene association studies yielded 104 papers (72 polymorphisms from 47 genes) that met inclusion criteria for analysis. Systematic meta-analysis was conducted on 6 polymorphisms (which had 3 or more published case-control cohorts from 69 papers) in the APOE, ACT, ACE, MTHFR, PON1, and PSEN-1 genes. Associations of increased risk for VCI were found for APOE ℇ4 (1.818 (95% CI = 1.611-2.053), p < 0.001; n = 3,554 cases, n = 12,277 controls) and MTHFR rs1801133 (1.323 (95% CI = 1.061-1.650) p = 0.013); n = 659 cases, n = 981 controls). There was marginal evidence of a protective effect for APOE ℇ2 (0.885 (95% CI = 0.783-0.999), p = 0.048; n = 3,320 cases, n = 10,786 controls). This systematic study of all published genetic association studies of sporadic VCI supports MTHFR and APOE as susceptibility genes for VCI. It also shows the utility of meta-analysis as a tool to identify potential candidate genes from numerous individual small-scale studies of diseases where sample recruitment may be limited for a variety of practical reasons. [ABSTRACT FROM AUTHOR]

Males (N = 72) were provided an opportunity to shoot a pellet gun at a female confederate in the context of a novel form of male entertainment. Two behavioral measures of aggression were the power of the gun chosen and the number of shots the participant elected to take. A procedural foul-up was staged wherein an assistant had inadvertently neglected to assign the subject to a condition of the experiment. The oversight ostensibly came to light immediately after the participant announced his decisions on the gun. A last-minute draw rectified matters and each participant discovered he was in the control condition. The confederate's plea for restraint was unsuccessful in mitigating the intensity and frequency of men's attacks. Those electing to take a greater number of shots scored higher on a measure of anti-social tendencies. A multiple regression analysis of factors predicting the attraction to such entertainment accounted for 59% of the variance and indicated that the overriding measure is men's expectation that the experience will be enjoyable. [ABSTRACT FROM AUTHOR]

Cases of tuberculosis (TB) resulting from infection with Mycobacterium tuberculosis complex (MTBC) have been recorded in captive white ( Ceratotherium simum ) and black ( Diceros bicornis ) rhinoceros. More recently, cases have been documented in free-ranging populations of both species in bovine tuberculosis (bTB) endemic areas of South Africa. There is limited information on risk factors and transmission patterns for MTBC infections in African rhinoceros, however, extrapolation from literature on MTBC infections in other species and multi-host systems provides a foundation for understanding TB epidemiology in rhinoceros species. Current diagnostic tests include blood-based immunoassays but distinguishing between subclinical and active infections remains challenging due to the lack of diagnostic techniques. In other species, demographic risk factors for MTBC infection include sex and age, where males and adults are generally at higher risk than females and younger individuals. Limited available historical information reflects similar age- and sex-associated patterns for TB in captive black and white rhinoceros, with more reports of MTBC-associated disease in black rhinoceros than in white rhinoceros. The degree of MTBC exposure in susceptible wildlife depends on their level of interaction, either directly with other infected individuals or indirectly through MTBC contaminated environments, which is dependent on the presence and abundance of infected reservoir hosts and the amount of MTBC shed in their excreta. Captive African rhinoceros have shown evidence of MTBC shedding, and although infection levels are low in free-ranging rhinoceros, there is a risk for intraspecies transmission. Free-ranging rhinoceros in bTB endemic areas may be exposed to MTBC from other infected host species, such as the African buffalo ( Syncerus caffer ) and greater kudu ( Tragelaphus strepsiceros ), through shared environmental niches, and resource co-utilization. This review describes current knowledge and information gaps regarding the epidemiology of TB in African rhinoceros., (Copyright © 2020 Dwyer, Witte, Buss, Goosen and Miller.)