Pneumatosis coli in a dog

A 17-year-old, castrated male Maltese was presented with chronic polyphagia and a 2-week history of tenesmus, diarrhea, hematochezia, weight loss, and ribbon-like feces. Pneumatosis coli was diagnosed by abdominal radiography. Concurrent hyperadrenocorticism was suspected. The clinical signs of colorectal disease resolved within 2 days of initiating a lowresidue diet and oral metronidazole. Pneumatosis coli should be considered as a differential diagnosis for colorectal disease in dogs.     

Influence of native catfish mucus on Flavobacterium columnare growth and proteolytic activity

Flavobacterium columnare causes columnaris disease of farmed and wild freshwater fish. Skin mucus is an important factor in early stages of columnaris pathogenesis, albeit little studied. Our objectives were to (a) characterize the terminal glycosylation pattern (TGP) of catfish mucus, (b) determine the growth of F. columnare in formulated water (FW)‐containing channel catfish (Ictalurus punctatus) or hybrid catfish (Ictalurus punctatus X Ictalurus furcatus) mucus and (c) examine extracellular protease activity of two F. columnare isolates differing in virulence. The TGP of catfish mucus by lectin binding was as follows: alpha‐D‐mannose/alpha‐D‐glucose >N‐acetyl‐beta‐D‐glucosamine >N‐acetyl‐beta‐D‐glucosamine/N‐acetylneuraminic acid >N‐acetyl‐D‐galactosamine >alpha‐D‐galactose/N‐acetyl‐alpha‐D‐galactosamine >beta‐D‐galactose = alpha‐L‐fucose. Virulence studies demonstrated isolate AL‐02‐36 was highly virulent in channel catfish fry (0.1 g) with cumulative mortality of 90%‐100% versus 60% for isolate ALG‐00‐530 at equivalent doses (~3 × 10⁶ CFU/ml); a similar result was observed in larger (0.7 g) catfish. In multiple experiments, F. columnare replicated (2‐3 logs) and survived (28 days) in formulated water‐containing catfish mucus. Highly virulent isolate AL‐02‐36 possessed at least 2.5‐ to fivefold higher protease activity following growth in mucus than the less virulent ALG‐00‐530. Flavobacterium columnare utilized catfish mucus as a nutrient source and mucus presence modulated extracellular protease production.     

The effects of dietary inclusion of a Saccharomyces cerevisiae fermentation product in a commercial catfish ration on growth,immune readiness,and columnaris disease susceptibility

ABSTRACT

We evaluated a Saccharomyces cerevisiae fermentation product (Diamond V Original XPC) in hybrid catfish (Ictalurus furcatus x I. punctatus) for its potential effects on growth, blood parameters, and disease resistance. The trial featured four levels of inclusion that were added to a commercial 32% protein floating catfish ration. Following six weeks of feeding, we observed marginally heightened resistance to columnaris disease and saw significant changes in the levels of immune effectors in the serum, including lysozyme, complement, and immunoglobulin.     

Plant and animal endemism in the eastern Andean slope: challenges to conservation

Background

The Andes-Amazon basin of Peru and Bolivia is one of the most data-poor, biologically rich, and rapidly changing areas of the world. Conservation scientists agree that this area hosts extremely high endemism, perhaps the highest in the world, yet we know little about the geographic distributions of these species and ecosystems within country boundaries. To address this need, we have developed conservation data on endemic biodiversity (~800 species of birds, mammals, amphibians, and plants) and terrestrial ecological systems (~90; groups of vegetation communities resulting from the action of ecological processes, substrates, and/or environmental gradients) with which we conduct a fine scale conservation prioritization across the Amazon watershed of Peru and Bolivia. We modelled the geographic distributions of 435 endemic plants and all 347 endemic vertebrate species, from existing museum and herbaria specimens at a regional conservation practitioner's scale (1:250,000-1:1,000,000), based on the best available tools and geographic data. We mapped ecological systems, endemic species concentrations, and irreplaceable areas with respect to national level protected areas.

Results

We found that sizes of endemic species distributions ranged widely (< 20 km² to > 200,000 km²) across the study area. Bird and mammal endemic species richness was greatest within a narrow 2500-3000 m elevation band along the length of the Andes Mountains. Endemic amphibian richness was highest at 1000-1500 m elevation and concentrated in the southern half of the study area. Geographical distribution of plant endemism was highly taxon-dependent. Irreplaceable areas, defined as locations with the highest number of species with narrow ranges, overlapped slightly with areas of high endemism, yet generally exhibited unique patterns across the study area by species group. We found that many endemic species and ecological systems are lacking national-level protection; a third of endemic species have distributions completely outside of national protected areas. Protected areas cover only 20% of areas of high endemism and 20% of irreplaceable areas. Almost 40% of the 91 ecological systems are in serious need of protection (= < 2% of their ranges protected).

Conclusions

We identify for the first time, areas of high endemic species concentrations and high irreplaceability that have only been roughly indicated in the past at the continental scale. We conclude that new complementary protected areas are needed to safeguard these endemics and ecosystems. An expansion in protected areas will be challenged by geographically isolated micro-endemics, varied endemic patterns among taxa, increasing deforestation, resource extraction, and changes in climate. Relying on pre-existing collections, publically accessible datasets and tools, this working framework is exportable to other regions plagued by incomplete conservation data.     

Visualizing ribosome biogenesis: parallel assembly pathways for the 30S subunit

Ribosomes are self-assembling macromolecular machines that translate DNA into proteins, and an understanding of ribosome biogenesis is central to cellular physiology. Previous studies on the Escherichia coli 30S subunit suggest that ribosome assembly occurs via multiple parallel pathways rather than through a single rate-limiting step, but little mechanistic information is known about this process. Discovery single-particle profiling (DSP), an application of time-resolved electron microscopy, was used to obtain more than 1 million snapshots of assembling 30S subunits, identify and visualize the structures of 14 assembly intermediates, and monitor the population flux of these intermediates over time. DSP results were integrated with mass spectrometry data to construct the first ribosome-assembly mechanism that incorporates binding dependencies, rate constants, and structural characterization of populated intermediates.