Red fluorescence in reef fish: A novel signalling mechanism?

Background  

At depths below 10 m, reefs are dominated by blue-green light because seawater selectively absorbs the longer, 'red' wavelengths beyond 600 nm from the downwelling sunlight. Consequently, the visual pigments of many reef fish are matched to shorter wavelengths, which are transmitted better by water. Combining the typically poor long-wavelength sensitivity of fish eyes with the presumed lack of ambient red light, red light is currently considered irrelevant for reef fish. However, previous studies ignore the fact that several marine organisms, including deep sea fish, produce their own red luminescence and are capable of seeing it.     

Development of real-time PCR assays for the detection and differentiation of Australian and European ranaviruses

Serious systemic disease in fish and amphibians is associated with the ranaviruses, epizootic haematopoietic necrosis virus (EHNV) and Bohle iridovirus (BIV) in Australia, and European sheatfish virus (ESV) and European catfish virus (ECV) in Europe. EHNV, ESV and ECV are recognized causative agents of the OIE (Office International des Epizooties) notifiable systemic necrotizing iridovirus syndrome and are currently identified by protein-based assays, none of which are able to rapidly identify the specific agents. The aim of this study was to develop TaqMan real-time PCR assays that differentiated these viruses using nucleotide sequence variation in two ranavirus genes. A conserved probe representing 100% sequence homology was used as a reference for virus-specific probes. The virus-specific probes produced a similar signal level to the conserved probe while those probes binding to non-target viral DNA produced an altered fluorescent curve. The pattern of probe binding was characteristic for each virus. Sensitivity, specificity and dynamic range of the assay were assessed. The test is currently useful as a research and initial screening tool, with the potential to become a sensitive and specific method for detection and differentiation of ranaviruses with further development.     

New concepts of coxofemoral joint stability and the development of a clinical stress-radiographic method for quantitating hip joint laxity in the dog

From mechanical principles and postmortem observations of coxofemoral joints of dogs, a hydrostatic mechanism influencing hip joint stability was discovered. This discovery led to the development of a stress-radiographic positioning method to quantitate hip joint laxity in dogs. The method incorporated 2 views with the dog in supine position and hips at neutral flexion/extension angle: a compression view, with the femoral heads fully seated in the acetabula; and a distraction view, with the femoral heads at maximal lateral displacement. An index measurement method was formulated to quantitate the relative degree of joint laxity appearing in either the compression or distraction view. Clinical evaluation of 6 dogs was done to compare the compression/distraction method with the standard hip-extended radiographic method. Also, the stress-radiographic method was performed on 16-week-old Borzoi and German Shepherd Dogs to compare the characteristics of inherent hip joint laxity in these breeds. In all dogs tested, hip joint laxity was masked by the standard hip-extended view as indicated by a 2.5-fold improvement in sensitivity to hip joint laxity of the new method (P less than 0.00001). Moreover, the mean hip joint laxity of 16-week-old German Shepherd Dogs exceeded the mean hip joint laxity of Borzois by 79% (P less than 0.00001). Reports in the literature document the incontrovertible association of hip joint laxity to the development of hip dysplasia in dogs. We believe the ability to accurately quantitate hip joint laxity will provide key diagnostic and prognostic criteria for the selection of pet dogs, and more importantly, breeding stock.     

Bacteriological studies of the problem "Epidemic losses in hares and deer in habitats with high cultivation of 00-rapeseed"

Within the scope of the research work for possible reasons of the so-called "wildlife mortality" more than 900 specimens of 440 animals (183 hares, 153 deer, 14 rabbits found dead, and 98 hares and 6 deer shot by hunters) were checked for the presence of Clostridia in inner organs. The results show that in 40.3% of the animals found dead but only in 13.3% of the hunted hares Clostridia were to be found. Out of the isolated Clostridia strains 24.4% could not be identified; potentially pathogenic species were found in 78.3% of isolates of hares, 81.7% of those of deer and in 9.2% of those of hunted hares. 23.9% of the isolates were C. perfringens. Considering the known epizootiology of clostridioses it can be concluded that clostridia certainly play a role in losses of wildlife, as well in hares as in deer. Triggering factors could lie in the kind of feed which is available for animals in modern agrarian landscape. During the critical period in autumn and winter there are mainly crop plants like rapeseed, wheat and barley only available for wildlife.     

Contribution to the knowledge of synanthropic flies in the Mongolian People's Republic.

A survey is given of 23 species of synathropic and synbovine Diptera collected in the years 1968, 1969 and 1972 in the Mongolian People's Republic by J. Minár. Besides the faunistical comments, the species of hygienic-epidemiological or public health importance are discussed.     

Canine Ear Disease*

Abstract— —The authors describe briefly the anatomy and histology of the normal ear and the histopathological changes associated with otitis. The bacteria and fungi associated with infections of the ear are discussed. The incidence and results of treatment of otitis externa in out-patient and hospitalised cases are reported and the techniques and results of surgical procedures for conditions of the ear are detailed.     

Parentage assignment with genotyping‐by‐sequencing data

In this paper, we evaluate using genotype‐by‐sequencing (GBS) data to perform parentage assignment in lieu of traditional array data. The use of GBS data raises two issues: First, for low‐coverage (e.g., <2×) GBS data, it may not be possible to call the genotype at many loci, a critical first step for detecting opposing homozygous markers. Second, the amount of sequencing coverage may vary across individuals, making it challenging to directly compare the likelihood scores between putative parents. To address these issues, we extend the probabilistic framework of Huisman (Molecular Ecology Resources, 2017, 17, 1009) and evaluate putative parents by comparing their (potentially noisy) genotypes to a series of proposal distributions. These distributions describe the expected genotype probabilities for the relatives of an individual. We assign putative parents as a parent if they are classified as a parent (as opposed to e.g., an unrelated individual), and if the assignment score passes a threshold. We evaluated this method on simulated data and found that (a) high‐coverage (>2×) GBS data performs similarly to array data and requires only a small number of markers to correctly assign parents and (b) low‐coverage GBS data (as low as 0.1×) can also be used, provided that it is obtained across a large number of markers. When analysing the low‐coverage GBS data, we also found a high number of false positives if the true parent is not contained within the list of candidate parents, but that this false positive rate can be greatly reduced by hand tuning the assignment threshold. We provide this parentage assignment method as a standalone program called AlphaAssign.     

Comparative oncology: The paradigmatic example of canine and human mast cell neoplasms

In humans, advanced mast cell (MC) neoplasms are rare malignancies with a poor prognosis. Only a few preclinical models are available, and current treatment options are limited. In dogs, MC neoplasms are the most frequent malignant skin tumours. Unlike low‐grade MC neoplasms, high‐grade MC disorders usually have a poor prognosis with short survival. In both species, neoplastic MCs display activating KIT mutations, which are considered to contribute to disease evolution. Therefore, tyrosine kinase inhibitors against KIT have been developed. Unfortunately, clinical responses are unpredictable and often transient, which remains a clinical challenge in both species. Therefore, current efforts focus on the development of new improved treatment strategies. The field of comparative oncology may assist in these efforts and accelerate human and canine research regarding diagnosis, prognostication, and novel therapies. In this article, we review the current status of comparative oncology approaches and perspectives in the field of MC neoplasms.     

Sources of soil CO2 in calcareous grassland with woody plant encroachment

Purpose

The objective of this study is to estimate the contribution of various sources that influence soil CO₂ concentrations in calcareous grassland.

Materials and methods

The research was performed at the Podgorski Kras plain (45?°33?? N, 13?°55?? E, 400?C430?m.a.s.l.) in the sub-Mediterranean region of Slovenia (SW Slovenia), where many meadows and pastures have been abandoned. In parallel to the measurement of soil respiration R _s, soil gas was sampled for stable isotope analysis. Samples were taken biweekly at two sites, Grassland and Invaded, from July 2008 until November 2010. In addition, daily variations in concentration and stable isotope composition of soil CO₂ were determined in May 2009. The partitioning of soil CO₂ concentrations was performed using stable isotope mass balance calculation.

Results and discussion

The concentration and isotope composition of soil CO₂ exhibited similar seasonal variations at both sites. Lower ??¹³C_CO2 values, ranging from ?28.2 to ?15.2 ??, which occurred during warm periods and higher values, up to ?12.1 ??, were typical of cold winter periods, from December to March. Organic sources were estimated to constitute between 78 and 99?% of total soil CO₂ during warmer periods from May until October. This contribution was lower during the winter, ranging from 46 to 77?%. In winter, the atmospheric component to soil CO₂ dominated, constituting up to 60?%. On average, the inorganic contribution was estimated to comprise 12?% of the soil CO₂ at all sampling locations. The contribution of this source to soil CO₂ concentration, at up to 41?%, was highest in Grassland during the growing season. The inorganic source of soil CO₂ was also an important component during daily variations. The highest contribution was observed during the day, in parallel to the highest respiration rates.

Conclusions

The inorganic pool is shown to be an important part of soil CO₂ in calcareous areas and should be considered as equal to organic CO₂ as a source in soil CO₂ partitioning.