Ecology of Badgers in Curlew Valley, Utah and Idaho With Emphasis on Movement and Activity Patterns

Between March, 1969 and July, 1970, 16 badgers (Taxidea taxus) were caught and fitted with radio transmitters in the southern part of Curlew Valley. The animals were followed telemetrically; seven animals contributed sufficient data from which home-range, movement and activity patterns could be discerned. The aver age annual home-range size of five females was 664 acres (± s.d. 99 .5 acres). Female home-range sizes were approximately the same within crested wheat-grass (Agropyron aristatum) and sagebrush (Artemisia tridentata) vegetation types, with greater distances traveled each night by females in the crested wheat-grass. Both home-range size and total movement were less during winter in the one badger observed during more than one season. The average home range of two males followed between September and mid-December was 1,440 acreas, twice the average female home-range size. The necropsy of badgers in the study collection and a scat collection yielded information on the food habits and breeding biology of badgers in Curlew Valley. Many prey species were used, but mice were the most frequently eaten food item. Badgers bred between mid-July and the end of August. Delayed implantation PE sisted until approximately January 26. Pregnant females gave birth to an average of 2.2 young about April 1

Estimating Domestic Sheep Losses to Mountain Lions

Large, native-range pastures were searched for dead domestic sheep in the Southern Bighorn Mountains of Wyoming. The proportion of dead sheep that had been killed by mountain lions was 23%. Search methods, however, resulted in unequal probabilities of finding sheep that were killed by mountain lions and sheep that died of other causes

Estimating Domestic Sheep Losses to Mountain Lions

Large, native-range pastures were searched for dead domestic sheep in the Southern Bighorn Mountains of Wyoming. The proportion of dead sheep that had been killed by mountain lions was 23%. Search methods, however, resulted in unequal probabilities of finding sheep that were killed by mountain lions and sheep that died of other causes

Genetic Structure of Cougar Populations Across the Wyoming Basin: Metapopulation or Megapopulation

We examined the genetic structure of 5 Wyoming cougar (Puma concolor) populations surrounding the Wyoming Basin, as well as a population from southwestern Colorado. When using 9 microsatellite DNA loci, observed heterozygosity was similar among populations (HO = 0.49–0.59) and intermediate to that of other large carnivores. Estimates of genetic structure (FST = 0.028, RST = 0.029) and number of migrants per generation (Nm) suggested high gene flow. Nm was lowest between distant populations and highest among adjacent populations. Examination of these data, plus Mantel test results of genetic versus geographic distance (P ≤ 0.01), suggested both isolation by distance and an effect of habitat matrix. Bayesian assignment to population based on individual genotypes showed that cougars in this region were best described as a single panmictic population. Total effective population size for cougars in this region ranged from 1,797 to 4,532 depending on mutation model and analytical method used. Based on measures of gene flow, extinction risk in the near future appears low. We found no support for the existence of metapopulation structure among cougars in this region

Epilepsy and intellectual disability linked protein Shrm4 interaction with GABA B Rs shapes inhibitory neurotransmission

Shrm4, a protein expressed only in polarized tissues, is encoded by the KIAA1202 gene, whose mutations have been linked to epilepsy and intellectual disability. However, a physiological role for Shrm4 in the brain is yet to be established. Here, we report that Shrm4 is localized to synapses where it regulates dendritic spine morphology and interacts with the C terminus of GABA B receptors (GABA B Rs) to control their cell surface expression and intracellular trafficking via a dynein-dependent mechanism. Knockdown of Shrm4 in rat severely impairs GABA B R activity causing increased anxiety-like behaviour and susceptibility to seizures. Moreover, Shrm4 influences hippocampal excitability by modulating tonic inhibition in dentate gyrus granule cells, in a process involving crosstalk between GABA B Rs and extrasynaptic \uce-subunit-containing GABA A Rs. Our data highlights a role for Shrm4 in synaptogenesis and in maintaining GABA B R-mediated inhibition, perturbation of which may be responsible for the involvement of Shrm4 in cognitive disorders and epilepsy

Current opinion on the role of testosterone in the development of prostate cancer: a dynamic model

Background: Since the landmark study conducted by Huggins and Hodges in 1941, a failure to distinguish between the role of testosterone in prostate cancer development and progression has led to the prevailing opinion that high levels of testosterone increase the risk of prostate cancer. To date, this claim remains unproven. Presentation of the Hypothesis: We present a novel dynamic mode of the relationship between testosterone and prostate cancer by hypothesizing that the magnitude of age-related declines in testosterone, rather than a static level of testosterone measured at a single point, may trigger and promote the development of prostate cancer. Testing of the Hypothesis: Although not easily testable currently, prospective cohort studies with population-representative samples and repeated measurements of testosterone or retrospective cohorts with stored blood samples from different ages are warranted in future to test the hypothesis. Implications of the Hypothesis: Our dynamic model can satisfactorily explain the observed age patterns of prostate cancer incidence, the apparent conflicts in epidemiological findings on testosterone and risk of prostate cancer, racial disparities in prostate cancer incidence, risk factors associated with prostate cancer, and the role of testosterone in prostate cancer progression. Our dynamic model may also have implications for testosterone replacement therapy