A novel approach to studying the effects of temperature on soil biogeochemistry using a thermal gradient bar

The temperature dependence of chemical reaction rates and microbial metabolism mean that temperature is a key factor regulating soil trace gas emissions and hydrochemistry. Here we evaluated a novel approach for studying the thermal response of soils, by examining the effects of temperature on gas emissions and hydrochemistry in (a) peat and (b) soil from a Sitka spruce plantation. A thermal gradient was applied along an aluminium bar, allowing soil to be incubated contemporaneously from 2 to 18 °C. The approach demonstrated clear differences in the biogeochemical responses of the two soil types to warming. The peat showed no significant emission of CH₄ at temperatures below 6 °C, while above 6 °C, a marked increase in the rate of release was apparent up to 15 °C (Q₁₀ = 2.5) with emissions being similar between 15 and 18 °C. Conversely, CH₄ emissions from the forest soil did not respond to warming. Nitrate availability in the peat decreased by 90% between 2 and 18 °C (P < 0.01), whereas concentrations in the forest soil did not respond. Sulphate availability in the peat decreased significantly with warming (60%, P < 0.01), while the forest soil showed the opposite response (a 30% increase, P < 0.01). Conventionally, thermal responses are studied by incubating individual soil samples at different temperatures, involving lengthy preparation and facilities to incubate samples at different temperatures simultaneously. Data collected on a given thermal response is usually limited and thus interpolated or extrapolated. The thermal gradient method overcomes these problems, is simple and flexible, and can be adapted for a wide range of sample types (not confined to soil). Such apparatus may prove useful in the optimization of management practices to mitigate the effects of climate change, as thermal responses will differ depending on land use and soil type.     

The Relationship Between Body Weight,Body Condition,and Survival in Cats with Heart Failure

Background: Obese people with heart failure have improved survival compared with their normal or underweight counterparts. The purpose of this study was to determine if there is a relationship between body weight or body condition and survival in cats with heart failure. Hypothesis: Body weight and body condition score (BCS) are predictors of survival in cats with heart failure. Animals: One‐hundred and one cats with heart failure (International Small Animal Cardiac Health Council Classes II, IIIa, or IIIb) evaluated between March 2007 and June 2009. Methods: Data regarding initial body weight and BCS, subsequent changes in body weight, and treatment were collected from records and compared with survival times. Results: Median initial body weight was 5.1 kg (range, 2.2–9.5 kg). Median BCS was 5 (range, 3–9). Of the 68 cats that were discharged from the hospital, median body weight change was 0.0 kg (range, ?2.6 to +2.3 kg). Survival time for all 101 cats was 93 days (0–811 days). Survival could be predicted using a model combining initial body weight (P= .02), body weight squared (P= .02), and survival to discharge (P < .001) with a resulting global P value for this model of P < .0001. Conclusions and Clinical Importance: Cats with the lowest and highest body weights had reduced survival times compared with those with body weights in the intermediate ranges, suggesting a U‐shaped relationship between body weight and survival. Additional research into the effects of body composition could help to determine optimal management of cats with heart failure.     

DISTRIBUTION AND DIAGNOSIS OF DIROFILARIASIS AND TOXOCARIASIS IN AUSTRALIA

SUMMARY: The prevalence of Dirofilaria immitis infection in dogs continues to increase in the temperate east coast zone of Australia (and is extending further south into New South Wales and Victoria). However, the infection rate has not changed in the tropics over the past 10 years where it would appear that a maximum infection rate of 90% occurs in a given Australian dog population. Twelve percent of Brisbane dogs had occult dirofilariasis and it is suggested that the proportion of occult infections was probably higher in the tropics. Dogs of all breeds appear equally susceptible to D. immitis with infection being more common in older male dogs. The level of microfilaraemia was, occasionally, proportional to the number of heartwprms per dog. Toxocara canis was present in about 75% of dogs from all areas studied except in Central Australia where the level of infection was much lower.
Immunodiagnosis of D. immitis and T. canis with high specificity and sensitivity was achieved by cyanogen bromide indirect fluorescent antibody and cell-mediated immunity tests using parasite antigens purified by affinity chromatography. These tests enabled occult dirofilariasis to be differentiated from unrelated canine cardiac and pulmonary failure. Such immunodiagnosis can aid in the early diagnosis of dirofilariasis particularly in situations where no circulating microfilariae can be detected.
The prevalence of serum antibody in man to purified Dirofilaria and Toxocara antigens was proportional to the incidence of respective canine infections at each location.     

Correlations of fatty acid supplementation, aeroallergens, shampoo, and ear cleanser with multiple parameters in pruritic dogs

Seventy-two pruritic dogs were fed one of four diets controlled for n-6:n-3 fatty acid ratios and total dietary intake of fatty acids. Multiple parameters were evaluated, including clinical and cytological findings, aeroallergen testing, microbial sampling techniques, and effects of an anti-fungal/antibacterial shampoo and ear cleanser. Significant correlations were observed between many clinical parameters, anatomical sampling sites, and microbial counts when data from the diet groups was combined. There were no statistically significant differences between individual diets for any of the clinical parameters. The importance of total clinical management in the control of pruritus was demonstrated.     

Ectopia cordis thoracoabdominalis in a piglet

A congenital anomaly characterised by displacement of the heart through a ventral body wall fissure involving the thoracic and cranial abdominal regions was recorded in a female Yorkshire-cross piglet. Dissection to assess the morphology of the developmental defect and a summary review of the literature on ectopia cordis were made. This case appears to be one of only three of ectopia cordis thoracoabdominalis reported in swine.     

Serial evaluation of protein C and antithrombin in dogs with sepsis

BACKGROUND: Protein C (PC) and antithrombin (AT) activities are decreased in humans with severe sepsis, and persistent changes are associated with decreased survival. In dogs with sepsis, PC and AT have been shown to be decreased at the time of diagnosis. HYPOTHESIS: PC and AT activities change significantly over time in dogs with sepsis and may be related to outcome. ANIMALS: Twelve dogs with naturally occurring sepsis. METHODS: Blood was collected from 12 dogs with sepsis, defined as histopathologic or microbiologic confirmation of infection and two of the following: hypo- or hyperthermia, tachycardia, tachypnea, leukopenia, leukocytosis, or >3% bands. The time of 1st sampling was considered day 1 and sampling was repeated every 24 hours for 5 days or until discharge or death. Changes over time were analyzed by ANOVA with repeated measures, and the association between PC and AT and outcome was determined by a 2-equation treatment effects model. RESULTS: Nine dogs and 11 dogs had decreased PC and AT activity on day 1, respectively (mean PC, 66.0 +/- 25.8%; mean AT, 48.1 +/- 16.5%). PC activity significantly decreased from day 1 to day 2 (P= .001), then increased over time. Changes in PC (P < .001) and AT (P < .001) over time were likely associated with outcome with nonsurvivors having lower PC and AT activities than survivors. CONCLUSION: Results of this preliminary study show that PC and AT activities change significantly over time in dogs with sepsis and both are likely related to survival.