Comparison of intranasal and intratracheal oxygen administration in healthy awake dogs.

Intranasal (IN) and intratracheal (IT) oxygen administration techniques were compared by measuring inspired oxygen concentrations (FIO2) and partial pressures of arterial oxygen (PaO2) in 5 healthy dogs at various IN (50, 100, 150, and 200 ml/kg of body weight/min) and IT (10, 25, 50, 100, 150, 200, and 250 ml/kg/min) oxygen flow rates. Intratracheal administration of oxygen permitted lower oxygen flow rates than IN administration. Each IT oxygen flow rate produced significantly higher FIO2 and PaO2 than the corresponding IN flow rate. An IT oxygen flow rate of 25 ml/kg/min produced FIO2 and PaO2 values equivalent to those produced by an IN oxygen flow rate of 50 ml/kg/min. An IT oxygen flow rate of 50 ml/kg/min produced FIO2 and PaO2 values equivalent to those produced by IN oxygen flow rates of 100 and 150 ml/kg/min. All IT oxygen flow rates greater than or equal to 100 ml/kg/min produced FIO2 and PaO2 values that were greater than FIO2 and PaO2 values produced by IN oxygen flow rates of 200 ml/kg/min. The lowest flow rates studied (50 ml/kg/min, IN, and 10 ml/kg/min, IT) produced PaO2 capable of maintaining 97% hemoglobin saturation, which should be adequate for most clinical situations. Arterial blood gas analysis and FIO2 measurements are necessary to accurately guide oxygen flow adjustments to achieve the desired PaO2 and to prevent oxygen toxicity produced by excessive FIO2.     

Circulating concentrations of immunoreactive inhibin and FSH during the estrous cycle of mares

A heterologous radioimmunoassay developed to measure inhibin in rat plasma was validated and used to characterize changes in peripheral concentrations of immunoreactive inhibin (ir-inhibin) in relation to follicle stimulating hormone (FSH) concentrations during the estrous cycle of mares. The primary antiserum used in the assay was developed against a synthetic porcine inhibin -subunit [(1-26)-Gly-Tyr] fragment. The same synthetic peptide was used for preparation of standards and tracer. Slopes of the dose-response curves for pooled estrus and diestrus mare plasma and equine follicular fluid were similar to the slopes for the porcine inhibin -subunit standard curve and porcine follicular fluid dose-response curve. Twelve mares were bled once daily beginning when diameter of the largest follicle reached ≤25 mm and continuing until 3 days after the end of an interovulatory interval (ovulation=Day 0). Each of the 12 interovulatory intervals were normalized to the mean length of the interovulatory interval (22.2 days; range, 19 to 26). There was an effect of day for concentrations of ir-inhibin (P<0.001) and FSH (P<0.006). Significant mean changes were as follows: 1) ir-inhibin decreased between Days 0 and 1, whereas FSH increased between Days 0 and 5; and 2) ir-inhibin increased between Days 7 and 12, whereas FSH decreased between Days 11 and 14. Mean concentrations of ir-inhibin and FSH were negatively correlated (r=-0.548; P<0.002). In conclusion, mean peripheral concentrations of ir-inhibin and FSH were inversely related during the estrous cycle of mares.     

Evaluation of a thoracic focused assessment with sonography for trauma (TFAST) protocol to detect pneumothorax and concurrent thoracic injury in 145 traumatized dogs

Objective: To estimate the relative accuracy of a thoracic focused assessment with sonography for trauma (TFAST) protocol for rapid diagnosis of pneumothorax (PTX) and other thoracic injury in traumatized dogs. Design: Prospective case series. Setting: Private veterinary emergency center. Animals: One hundred and forty‐five client‐owned dogs evaluated within 24‐hours of injury. Interventions: Thoracic focused assessment with sonography for trauma protocol. Measurements and Main Results: Traumatized dogs were evaluated with a conventional ultrasound (US) machine using a standardized 4‐point thoracic FAST protocol before thoracic radiography (CXR) and thoracocentesis. PTX was diagnosed by the absence of the ‘glide sign,’ defined as the lack of the normal dynamic interface between lung margins gliding along the thoracic wall during respiration. Concurrent thoracic trauma was diagnosed by the presence of pleural or pericardial fluid or the presence of a ‘step sign,’ defined as an abnormal glide sign. Accuracy of TFAST was calculated relative to CXR findings. Results: Overall sensitivity (Se), specificity (Sp), and accuracy of TFAST relative to CXR were 78.1% (95% CI; 61.5, 89.9), 93.4% (95% CI; 87.4, 97.1), and 90.0%, respectively. Se and Sp were higher in dogs with penetrating trauma (93.3%, 96.0%) and for the evaluator with the most clinical experience (95.2%, 96.0%); only Se between the most experienced compared with others was statistically significant (P<0.05). TFAST documented other concurrent thoracic injury. Median time for TFAST was 3 minutes. Conclusions and Clinical Relevance: TFAST has the potential to rapidly diagnose PTX and other thoracic injury and guide therapy, including potentially life‐saving interventions, in traumatized dogs.     

Application of for the identification and management of hybrid poplar accessions

Molecular markers are a powerful tool with many potential applications in agriculture and forestry. In particular, can provide information on the relatedness of various clones or varieties that are difficult to distinguish morphologically, thus helping in the management of plant accessions and in breeding programs. The goal of this study is to genotype 15 clones used in the Prairie Farm Rehabilitation Administration (PFRA) breeding programs. Simple Sequence Repeat (SSR, or microsatellite markers) were selected for genotyping using the polymerase chain reaction (PCR). This type of marker is considered the method of choice due to their abundance, polymorphism and reliability compared to other types of . Sixteen previously isolated and characterized in aspen (Populus tremuloides) and other poplar species (Populus spp.) were initially tested. Nine markers were selected based on the “informativeness” and the quality of the amplification products. The nine markers were combined in groups of three to improve the efficiency of the genotyping technique. Using the nine markers, the average number of alleles per locus was 5.1. The expected and observed heterozygosity ranges were 0.32 to 0.80 and 0.13 to 0.92 respectively. The results also show that it is possible to produce a unique “DNA fingerprint” specific to each of the 15 hybrid poplar clones with the nine . In this study it was possible to show that two clones, P. ‘Melville’ and P. x ‘Walker’ used in Saskatchewan have similar DNA profiles with nine markers and a combined probability of identity of 2.23×10⁻⁶ suggesting that these clones are identical. This observation will prevent unnecessary duplication of the two accessions in breeding programs. This revised version was published online in August 2006 with corrections to the Cover Date.     

Regenerative adsorption and removal of H2S from hot fuel gas streams by rare earth oxides

Sorbent materials that allow for high-temperature, regenerative desulfurization of fuel gas streams for the anode of a solid oxide fuel cell have been developed. Reversible adsorption of H2S on cerium and lanthanum oxide surfaces is demonstrated over many cycles at temperatures as high as 800 degrees C, on both fresh or presulfided sorbents, and at very high space velocities. The adsorption and desorption processes are very fast, and removal of H2S to sub-parts per million levels is achieved at very short (millisecond) contact times. Any type of sulfur-free gas, including water vapor, can be used to regenerate the sorbent surface. Preferably, the anode off-gas stream is used to sweep the desorbed H(2)S to a burner.     

Substrate-controlled succession of marine bacterioplankton populations induced by a phytoplankton bloom

Phytoplankton blooms characterize temperate ocean margin zones in spring. We investigated the bacterioplankton response to a diatom bloom in the North Sea and observed a dynamic succession of populations at genus-level resolution. Taxonomically distinct expressions of carbohydrate-active enzymes (transporters; in particular, TonB-dependent transporters) and phosphate acquisition strategies were found, indicating that distinct populations of Bacteroidetes, Gammaproteobacteria, and Alphaproteobacteria are specialized for successive decomposition of algal-derived organic matter. Our results suggest that algal substrate availability provided a series of ecological niches in which specialized populations could bloom. This reveals how planktonic species, despite their seemingly homogeneous habitat, can evade extinction by direct competition.     

Behavioral Interference Between Sympatric Reindeer and Domesticated Sheep in Norway

Interspecific interaction among sympatric ungulates is important in management and conservation. We investigated behavioral interference between sympatric wild or semidomestic reindeer (Rangifer tarandus tarandus) and sheep (Ovis aries) in two field studies and one enclosure experiment. For free-ranging wild and semidomestic reindeer, interference between the two species increased with decreasing distances, occurring only at less than 200 m and 30 m, for wild and semidomestic reindeer, respectively, and neither species consistently dominated the other. In a controlled, duplicated experiment we tested interference and confrontations at the feeding patch level among semidomestic reindeer and sheep within 40 × 50 m enclosures. When new reindeer or sheep were introduced into enclosures already occupied by reindeer, new reindeer resulted in significantly more interference and confrontations among individuals compared to new sheep; i.e., intraspecific interference was more prevalent than interspecific interference at equal densities. For all study areas, confrontations decreased with time after “first encounter,” indicating cohabituation. A sympatric use of pastures was not visually disruptive for recorded grazing behavior for either species.     

Incidence and treatment of inadequate postovulatory progesterone concentrations in repeat breeder cows

The incidence of low day 5 milk progesterone in dairy cows has been investigated and the efficacy of treating the problem assessed. The incidence of inadequate milk progesterone (empirically defined as <3ng/mL) in repeat breeder cows was 34% compared with 11.4% in first insemination cows. Treatment with an intravaginal progesterone device for 7 days starting from day 5 or 6 did not improve pregnancy rate. Treatment with 1500 iu human chorionic gonadotrophin (hCG) on day 5 gave an increase in pregnancy rate that was dependent on initial progesterone concentration and significant (P<0.05) in multiparous but not primiparous cows. While the incidence of inadequate day 5 progesterone was high in repeat breeder cows, it was responsive to hCG treatment, although only in multiparous and not primiparous animals.