Pulmonary Hypertension and Cardiac lnsuff iciency in Three Cows with Primary Lung Disease

Increased pulmonary arterial pressures as a result of pulmonary disease are described in two cows with chronic pneumonia and one cow with acute pneumonia. Based on clinical signs of congestive right heart failure, increased pulmonary arterial pressure, and right ventricular hypertrophy, cor pulmonale was diagnosed in one cow. Two cows had increased pulmonary arterial pressure and signs of right heart insufficiency, but right ventricular hypertrophy was not identified. Two of the cows had ventral edema and exercise intolerance. All cows had jugular venous distention and increased right atrial and pulmonary arterial pressures. Peripheral arterial PaO2 was decreased in two cows, and not measured in the third cow. Although an uncommon cause of congestive heart failure in cattle at low altitudes, pulmonary hypertension should be considered in cattle with clinical right heart failure.     

The use of traits to interpret responses to large scale - edge effects: a study of epigaeic beetle assemblages across a <Emphasis Type="Italic">Eucalyptus</Emphasis> forest and pine plantation edge

Context

Edge effects due to habitat loss and fragmentation have pervasive impacts on many natural ecosystems worldwide.

Objective

We aimed to explore whether, in tandem with the resource-based model of edge effects, species feeding-guild and flight-capacity can help explain species responses to an edge.

Methods

We used a two-sided edge gradient that extended from 1000 m into native Eucalyptus forest to 316 m into an exotic pine plantation. We used generalised additive models to examine the continuous responses of beetle species, feeding-guild species richness and flight-capable group species richness to the edge gradient and environmental covariates.

Results

Phytophagous species richness was directly related to variation in vegetation along the edge gradient. There were more flight-capable species in Eucalyptus forest and more flightless species in exotic pine plantation. Many individual species exhibited multiple-peaked edge-profiles.

Conclusions

The resource based model for edge effects can be used in tandem with traits such as feeding-guild and flight-capacity to understand drivers of large scale edge responses. Some trait-groups can show generalisable responses that can be linked with drivers such as vegetation richness and habitat structure. Many trait-group responses, however, are less generalisable and not explained by easily measured habitat variables. Difficulties in linking traits with resources along the edge could be due to unmeasured variation and indirect effects. Some species’ responses reached the limits of the edge gradient demonstrating the need to examine edge effects at large scales, such as kilometres.

     

Concurrent infection with ranavirus, Batrachochytrium dendrobatidis, and Aeromonas in a captive anuran colony

Four species (Dendrobates auratus, Phyllobates terribilis, Pyxicephalus adspersus, and Rhacophorus dennysi) of captive anurans with a clinical history of lethargy and inappetence were found dead and were submitted for necropsy. Gross lesions included irregular patches of sloughed skin and rare dermal ulcerations. Histologic findings included epidermal proliferation that was most pronounced on the digits and that included intracytoplasmic chytrid organisms. Bacteria were often associated with the epidermal lesions. Intracytoplasmic inclusion bodies were observed in hepatocytes. Real-time polymerase chain reaction yielded positive results for both Ranavirus and Batrachochytrium dendrobatidis (Bd). Bacterial culture of internal organs yielded Aeromonas hydrophila. This is the first report of concurrent infections in anurans by Ranavirus and Bd and A. hydrophila.     

Feed Containing Novacq Improves Resilience of Black Tiger Shrimp,Penaeus Monodon,to Gill‐associated Virus‐induced Mortality

The ability of Novacq to improve resilience of black tiger shrimp, Penaeus monodon, to infection and mortality induced by gill‐associated virus (GAV) was investigated. Over a 26‐d period, shrimp were fed pellets with or without 10% Novacq. Following this, four replicate tanks, each containing 10 shrimp that had been fed either diet, were maintained as‐is, injected with saline or injected with GAV inoculum (i.e., 40 shrimp for each of the six groups). For shrimp (n = 20) in two of each group of four tanks, survival was monitored daily over 14 d and a pleopod was sampled from each shrimp on Days 0 and 14. For the other two tanks, a pleopod was sampled from each shrimp on Days 0, 3, 7, 10, and 14 to track changes in GAV loads over time. Survival was significantly higher (P < 0.05) from Day 7 onward among the group fed Novacq. GAV infection loads appeared to vary more between individuals in the Novacq diet cohort, but overall were not reduced significantly at any time points post‐challenge compared to shrimp tested from the Control diet cohort.     

Presence of residual material following mini-hemilaminectomy in dogs with thoracolumbar intervertebral disc extrusion

Presence of residual material following mini-hemilaminectomy in dogs (n = 9) with spontaneous thoracolumbar intervertebral disc extrusion was prospectively investigated. Volume of extruded disc material within the vertebral canal and the proportion of residual material were determined using pre- and post-operative magnetic resonance imaging. The degree of spinal cord compression, proportion of extradural material considered hemorrhage, and invasion of the articular facets were also determined. Residual material was identified in 44% of the mini-hemilaminectomies. The median percentage of residual material calculated was 7.7% of the preoperative volume. No observed effect of surgical side or site, proportion of extradural material considered hemorrhage, patient weight, and duration of clinical signs was detected.     

Fire history and fire–climate relationships along a fire regime gradient in the Santa Fe Municipal Watershed, NM, USA

The Santa Fe municipal watershed provides up to 40% of the city's water and is at high risk of a stand-replacing fire that could threaten the water resource and cause severe ecological damage. Restoration and crown fire hazard reduction in the ponderosa pine (PP) forest is in progress, but the historic role of crown fire in the mixed-conifer/aspen (MC) and spruce-dominated forests is unknown but necessary to guide management here and in similar forests throughout the southwestern United States. The objective of our study was to use dendroecological techniques to reconstruct fire history and fire–climate relationships along an elevation, forest type, and fire regime gradient in the Santa Fe River watershed and provide historical ecological data to guide management. We combined systematic (gridded) sampling of forest age structure with targeted sampling of fire scars, tree-ring growth changes/injuries, and death dates to reconstruct fire occurrence and severity in the 7016 ha study area (elevation 2330–3650 m). Fire scars from 141 trees (at 41 plots) and age structure of 438 trees (from 26 transects) were used to reconstruct 110 unique fire years (1296–2008). The majority (79.0%) of fires burned during the late spring/early summer. Widespread fires that scarred more than 25% of the recording trees were more frequent in PP (mean fire interval (MFI)_25% = 20.8 years) compared to the MC forest (31.6 years). Only 24% of the fires in PP were recorded in the MC forest, but these accounted for a large percent of all MC fires (69%). Fire occurrence was associated with anomalously wet (and usually El Niño) years preceding anomalously dry (and usually La Niña) years both in PP and in the MC forest. Fire in the MC occurred during more severe drought (mean summer Palmer Drought Severity Index; PDSI = −2.59), compared to the adjacent PP forest (PDSI = −1.03). The last fire in the spruce forest (1685) was largely stand-replacing (1200 ha, 93% of sampled area), recorded as fire scars at 68% of plots throughout the MC and PP forests, and burned during a severe, regional drought (PDSI = −6.92). The drought–fire relationship reconstructed in all forest types suggests that if droughts become more frequent and severe, as predicted, the probability of large, severe fire occurrence will increase.     

Effect of delayed colostrum collection on colostral IgG concentration in dairy cows

OBJECTIVE: To determine the effect of timing of first-milking colostrum collection on colostral IgG concentration. DESIGN: Prospective study. ANIMALS: 13 healthy Holstein cows. PROCEDURES: All calvings were observed. After parturition, calves were not allowed to suckle and were separated from the dam. Colostrum was collected from a single randomly selected quarter at 2, 6, 10, and 14 hours after parturition until all 4 quarters were sampled. Colostral IgG concentration was determined via radial immunodiffusion. RESULTS: Mean colostral IgG concentration was 113, 94, 82, and 76 g/L at 2, 6, 10, and 14 hours after calving, respectively. Colostrum collected 6, 10, and 14 hours after calving had significantly lower IgG concentrations than did colostrum collected 2 hours after calving. Mean colostral IgG concentration at 14 hours after calving was significantly lower than that at 6 hours after calving. Cows in their third or greater lactation had mean colostral IgG concentrations 2 hours after calving (132 g/L) that were greater than the first and second lactation cows (mean, 95 and 100 g/L, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that early or immediate colostrum collection from dairy cows will maximize colostral IgG concentration. Adjustment of routine dairy farm management procedures may be required to maximize colostrum quality and minimize prevalence of failure of passive transfer in dairy calves.     

Rocket launcher mechanism of collaborative actin assembly defined by single-molecule imaging

Interacting sets of actin assembly factors work together in cells, but the underlying mechanisms have remained obscure. We used triple-color single-molecule fluorescence microscopy to image the tumor suppressor adenomatous polyposis coli (APC) and the formin mDia1 during filament assembly. Complexes consisting of APC, mDia1, and actin monomers initiated actin filament formation, overcoming inhibition by capping protein and profilin. Upon filament polymerization, the complexes separated, with mDia1 moving processively on growing barbed ends while APC remained at the site of nucleation. Thus, the two assembly factors directly interact to initiate filament assembly and then separate but retain independent associations with either end of the growing filament.