Mapping cerebellar abiotrophy in Australian Kelpies

An autosomal recessive form of cerebellar abiotrophy occurs in Australian Kelpie dogs. Clinical signs range from mild ataxia with intention tremor to severe ataxia with seizures. A whole‐genome mapping analysis was performed using Affymetrix Canine SNP array v2 on 11 affected and 19 control dogs, but there was no significant association with disease. A homozygosity analysis identified a three megabase region likely to contain the disease mutation. The region spans 29.8–33 Mb on chromosome 3, for which all affected dogs were homozygous for a common haplotype. Microsatellite markers were developed in the candidate region for linkage analysis that resulted in a logarithm of odds score suggestive of linkage. The candidate region contains 29 genes, none of which are known to cause ataxia.     

Differential Impact of Two Risk Communications on Antipsychotic Prescribing to People with Dementia in Scotland: Segmented Regression Time Series Analysis 2001–2011

Background

Regulatory risk communications are an important method for disseminating drug safety information, but their impact varies. Two significant UK risk communications about antipsychotic use in older people with dementia were issued in 2004 and 2009. These varied considerably in their content and dissemination, allowing examination of their differential impact.

Methods

Segmented regression time-series analysis 2001–2011 for people aged ≥65 years with dementia in 87 Scottish general practices, examining the impact of two pre-specified risk communications in 2004 and 2009 on antipsychotic and other psychotropic prescribing.

Results

The percentage of people with dementia prescribed an antipsychotic was 15.9% in quarter 1 2001 and was rising by an estimated 0.6%/quarter before the 2004 risk communication. The 2004 risk communication was sent directly to all prescribers, and specifically recommended review of all patients prescribed relevant drugs. It was associated with an immediate absolute reduction in antipsychotic prescribing of 5.9% (95% CI −6.6 to −5.2) and a change to a stable level of prescribing subsequently. The 2009 risk communication was disseminated in a limited circulation bulletin, and only specifically recommended avoiding initiation if possible. There was no immediate associated impact, but it was associated with a significant decline in prescribing subsequently which appeared driven by a decline in initiation, with the percentage prescribed an antipsychotic falling from 18.4% in Q1 2009 to 13.5% in Q1 2011. There was no widespread substitution of antipsychotics with other psychotropic drugs.

Conclusions

The two risk communications were associated with reductions in antipsychotic use, in ways which were compatible with marked differences in their content and dissemination. Further research is needed to ensure that the content and dissemination of regulatory risk communications is optimal, and to track their impact on intended and unintended outcomes. Although rates are falling, antipsychotic prescribing in dementia in Scotland remains unacceptably high.     

Recruitment and diversification of an ecdysozoan family of neuropeptide hormones for black widow spider venom expression

Venoms have attracted enormous attention because of their potent physiological effects and dynamic evolution, including the convergent recruitment of homologous genes for venom expression. Here we provide novel evidence for the recruitment of genes from the Crustacean Hyperglycemic Hormone (CHH) and arthropod Ion Transport Peptide (ITP) superfamily for venom expression in black widow spiders. We characterized latrodectin peptides from venom gland cDNAs from the Western black widow spider (Latrodectus hesperus), the brown widow (Latrodectus geometricus) and cupboard spider (Steatoda grossa). Phylogenetic analyses of these sequences with homologs from other spider, scorpion and wasp venom cDNAs, as well as CHH/ITP neuropeptides, show latrodectins as derived members of the CHH/ITP superfamily. These analyses suggest that CHH/ITP homologs are more widespread in spider venoms, and were recruited for venom expression in two additional arthropod lineages. We also found that the latrodectin 2 gene and nearly all CHH/ITP genes include a phase 2 intron in the same position, supporting latrodectin's placement within the CHH/ITP superfamily. Evolutionary analyses of latrodectins suggest episodes of positive selection along some sequence lineages, and positive and purifying selection on specific codons, supporting its functional importance in widow venom. We consider how this improved understanding of latrodectin evolution informs functional hypotheses regarding its role in black widow venom as well as its potential convergent recruitment for venom expression across arthropods.     

Bioacoustic monitoring of aggression in group-housed rhesus macaques

Many captive primate facilities house rhesus macaques in multimale-multifemale social groups in large enclosures that simulate the natural social and environmental features characteristic of the species, enhancing their reproductive performance as well as their psychological well-being, yet one of the most difficult management problems in socially housed macaques is their propensity for exhibiting spontaneous bouts of deleterious aggression. To address this management problem, an automated bioacoustic monitoring system might be developed that is capable of detecting and forecasting problematic patterns of contact aggression. To evaluate the utility of this approach, this study examined the magnitude of aggression and the co-occurrence of certain vocalization types and aggression in 10 groups of rhesus macaques. The data confirmed aggression as a significant problem in rhesus groups and indicated that certain patterns of vocalizations are indicative of the type or level of aggression. The detection and classification of these vocalization types need further research to eventually design and implement an efficacious bioacoustic system for monitoring aggression in rhesus macaques.     

Colonization of a portion of the bovine tongue by unusual filamentous bacteria.

Tongue samples from cattle on varied diets and ranging in age from 2 months to adult were studied by transmission and scanning electron microscopy to observe the in situ distribution and adhesion patterns of two readily identifiable genera of filamentous bacterial. The two, both members of the Simonsiellaceae, adhere to the epithelium by means of fibers which are produced on one side of the bacterial filaments and subsequently display a sidedness in their manner of adhesion to epithelial surfaces. Other bacterial populations found on the tongue were normally members of chains and seldom present as single cells. This suggests that filamentous or chain-forming bacteria may have a selective advantage over single bacteria in their ability to colonize and remain attached to the epithelium of the tongue.     

Policing in Nonhuman Primates: Partial Interventions Serve a Prosocial Conflict Management Function in Rhesus Macaques

Studies of prosocial policing in nonhuman societies traditionally focus on impartial interventions because of an underlying assumption that partial support implies a direct benefit to the intervener, thereby negating the potential for being prosocial in maintaining social stability for the benefit of the group. However, certain types of partial interventions have significant potential to be prosocial in controlling conflict, e.g. support of non-kin subordinates. Here, we propose a policing support hypothesis that some types of agonistic support serve a prosocial policing function that maintains group stability. Using seven large captive groups of rhesus macaques, we investigated the relationship between intervention type and group-level costs and benefits (rates of trauma, severe aggression, social relocation) and individual level costs and benefits (preferential sex-dyad targeting, dominance ambiguity reduction, access to mates, and return aggression). Our results show that impartial interventions and support of subordinate non-kin represent prosocial policing as both (1) were negatively associated with group-level rates of trauma and severe aggression, respectively, (2) showed no potential to confer individual dominance benefits, (3) when performed outside the mating season, they did not increase chances of mating with the beneficiary, and (4) were low-cost for the highest-ranking interveners. We recommend expanding the definition of ‘policing’ in nonhumans to include these ‘policing support interventions’.     

The tempo of genetic evolution in birds: body mass and climate effects

Aim Negative relationships between body mass and substitution rates have previously been reported. However, most of these studies have involved contrasted taxa that, due to their highly divergent phylogenetic histories, also differ in many additional characteristics other than mass. In particular, there has been little examination of the potentially confounding effects of climate or population size. Here we test for differences in rates of microevolution among bird species that, although differing in mass, are nonetheless very closely related phylogenetic pairs. We additionally tested for latitudinal/elevational and population size effects across these contrasts. Location Global. Methods The tempo of microevolution within the cytochrome b gene of mitochondrial DNA was compared between closely related bird species that differed in body mass, using 130 phylogenetically independent species pairs. In order to minimize climate effects, pairs not having overlapping latitudinal ranges were discarded. In addition, a subset of pairs was identified and analysed that involved comparisons between species that have different latitudinal or elevational midpoints. Results Species with smaller mass had substitution rates marginally faster than those with larger mass (small : large median ratio = 1.05). However, this result was only statistically significant when data were pruned to eliminate comparisons in which population or range size also varied substantially between contrasted species. Latitude and elevation had a much stronger association with substitution rates than body mass within the subset of pairs (n = 30) that also differed in their spatial distributions: lower elevation or latitude species had substantially more substitutions than those at higher latitudes or elevations (low : high ratio = 1.35). Furthermore, when the dataset was pruned of pairs in which body mass was confounded by latitude or elevation, the body mass effect was eliminated. Main conclusions Body mass is known to correlate with latitude, so that the latitudinal/elevational association with microevolution we found might either be additive to, or causal of, the body mass effect. These results are consistent with the evolutionary speed hypothesis, which suggests that latitudinal diversity gradients derive from variation in the rate of microevolution. Our findings also serve to raise concerns about biogeographical studies that use genetic distances between taxa to estimate time since divergence.     

A New Quantitative Technique for Categorizing Whistles Using Simulated Signals and Whistles from Captive Bottlenose Dolphins (Delphinidae,Tursiops truncatus)

A widespread problem in the study of animal vocalizations is evaluating the acoustic similarity of signals both between individuals of a social group and between social groups. This problem becomes especially salient when classifying the narrow-band frequency-modulated signals, such as whistles, found in many avian and mammalian species. Whistles are usually characterized by their relative change in frequency over time, known as whistle ‘contour’. Measuring such a characteristic is difficult as it is not a single measurement, such as the mean frequency or duration of a signal, but several associated measurements of frequency across time. This paper reports on a new quantitative technique for determining whistle types based on whistle contour similarity and an application of this technique to the whistles of bottlenose dolphins to demonstrate its utility. This ‘contour similarity’ technique (CS technique) uses cluster analysis to group the correlation coefficients of frequency measurements from a data set of signals. To demonstrate the efficacy of this CS technique, three data sets were analysed, two using computer-generated signals and a third using adult bottlenose dolphin whistles, to (1) examine the efficacy of correlation coefficients for grouping signals by their similarity in whistle contour and (2) determine the viability of this technique for categorizing bottlenose dolphin whistles. Measured actual frequencies and correlation matrices from the four simulated signal types and a correlation matrix from the whistles of five captive adult bottlenose dolphins were each subjected to K-means cluster analysis and the resulting signal types were evaluated. Results indicated that the technique grouped actual frequencies according to the amount of shared actual frequencies and grouped correlation coefficients successfully according to signal contour. This result endured even if contours differed in overall duration or actual frequency or were expanded or compressed with respect to frequency or time. The results suggest that this approach is a viable method for assigning whistle contours to categories in bottlenose dolphins or any other species with narrow-band, frequency-modulated signals.