Crosspin Fixation of Fractures of the Proximal Tibia in Three Foals

Three foals, each less than 1 month of age, were presented with Salter Type II fractures of the proximal tibial physis. Reduction of the fractures was accomplished manually and maintained by crosspin fixation. Fracture healing in two of the foals was uncomplicated. The third foal developed an infection around the implants, which responded to periodic local antiseptic flushing and administration of penicillin and gentamicin. Follow-up information ranging from 11 to 22 months after surgery revealed satisfactory results in two of three foals; premature closure of the proximal tibial physis was found in the other foal, resulting in the development of an angular limb deformity.     

Critical Transport Infrastructure in Urban Areas: Impacts of Traffic Incidents Assessed Using Accessibility‐Based Network Vulnerability Analysis

Incidents (vehicle breakdowns, crashes, roadworks, lane blockages, severe weather, etc.) are believed responsible for about 50 percent of traffic congestion in Australia's major cities, which is a similar situation to that found in cities in many other parts of the developed world. Incident‐based congestion is particularly disruptive because of its random occurrence in space and time, which maximises the operational impacts of the congestion on social and economic activities. This paper discusses a method for assessing critical locations—congestion “hot spots”—in urban road networks, and the development and application of diagnostic tools that will allow urban road system managers to anticipate potential vulnerabilities to incident‐related congestion and take proactive action to avoid congestion rather than react to it. The expected outcomes are then reduced congestion, delays, and pollution; significantly improved performance from the existing urban road system; and reduced pressure to build more roads. The method involves modelling of travel demand, network topology, capacity and road geometry, the identification and assessment of impacts of traffic incidents at specific locations in a road network, and the use of accessibility impact analysis to assess system‐wide effects. Accessibility impact analysis is undertaken using an accessibility framework, which can account for time of day, transport mode and destination choices by individuals, and level of traffic congestion among other factors. A case‐study application to a specific (potential) incident in a real‐world network indicates that the proposed method is feasible and demonstrates its power in identifying not just total impacts but the distribution of those impacts across a region or community. While current approaches to urban road network planning and management tend to be reactive—finding cures for problems as they arise or addressing locations of recurrent congestion or bad incident record—the vulnerability analysis method described in the paper should lend itself to a proactive approach that can anticipate structural weaknesses and vulnerabilities and help to avoid or at least temper potential adverse effects, rather than to react to them afterwards.     

Growth and viability of hatchery-reared Argyrosomus japonicus released into open and semi-closed systems

Abstract  Hatchery-reared Argyrosomus japonicus (Temminck & Schlegel) were released into estuaries of varying habitat between 1996 and 2004, and growth and recruitment to the fishery evaluated. Fish stocked earlier in summer had significantly faster growth rates ( P  < 0.01), and post-stocking mortality ranged from 1.1% to 11.7% within 7 day post-release. Argyrosomus japonicus stocked in the Georges River in 2003 and 2004 yielded fishery independent recapture rates up to 0.2%. For A. japonicus stocked in Smith's Lake in 1997 and 2004, growth rates, timing of recaptures and increases in commercial catches suggested recruitment to the fishery by 18 months. The 1997 stocking led to a 30-fold increase in A. japonicus catch, but stocking was not financially viable, with a cost:benefit ratio of 2.1. Small, shallow coastal lagoons may represent experimental units for refining stocking strategies, but are not optimal for A. japonicus . The potential for density-dependent effects, and complex relationships between growth, habitat and mortality, highlighted the need for a thorough understanding of species – system interactions. Pilot releases can contribute to this understanding, particularly assessment of habitat requirements, and season, site and size-of-release.     

Anesthesia and pain management in Russia

There was only limited emphasis on anesthesia and pain management in veterinary colleges in Russia until the last ten years. There is now great interest in improvement by Russia practitioners. This effort is hampered by the lack of approved and available medications and limited instructions. At this time, the small animal practitioners have tranquilizers, alpha₂ agonists local anesthetics and NSAID's for their use. Propofol is available through pharmacies and efforts are being made for veterinarians to use ketamine. Only a few practices have inhalant anesthetic units and halothane. During a recent lecture tour of Russia, general clinical principles and specific anesthetic and pain management protocols were taught. The audience, primarily young and progressive veterinarians, actively participated and showed great desire to practice quality anesthesia and pain management for their patients. Teaching young veterinarians how to manage their cases without the availability of opioids, ketamine advanced anesthetic equipment and monitors was indeed challenging. Protocols for perioperative management consisting of medetomidine with or without local anesthesia followed by carprofen for post-operative pain is an improvement. We sometimes spend so much time discussing which of many drug combinations we will use but seldom consider what we would do if we were practicing our specialty in parts of the world where we would have to modify dosages and combinations to achieve humane care with few drug choices.     

Progressive tetraparesis and laryngeal paralysis in a young Rottweiler with neuronal vacuolation and axonal degeneration: an Australian case

A 5-month-old female Rottweiler dog was diagnosed to have a neurodegenerative disease that has been recently report ed in Rottweilers from North America and Europe. The dog was presented with progressive signs of ataxia, tetraparesis and inspiratory stridor. The clinical investigation included analysis of CSF, radiography, myelography and electrophysiolog-ical testing. No evidence of vertebral malformation or inflammatory CNS disease was identified. Bilateral laryngeal paraly sis was identified in the lightly anaesthetised dog. Electromyography showed abnormal spontaneous activity from the intrin sic musculature of the larynx. At necropsy there were no gross abnormalities of the nervous system but there was atrophy of the dorsal cricoarytenoid muscles of the larynx. There were widespread histological abnormalities throughout the ner vous system including neuronal vacuolation, spongiform changes in the neuropil and axonal degeneration which was most prominent in the spinal cord. These clinical and pathological findings are consistent with the diagnosis of a new neurode-generative disease reported from North America and Europe. This diagnosis is of particular significance in Australia where transmissible spongiform encephalopathies have not been identified.     

EFFECT OF pH ON PHOSPHATE ADSORPTION AND ISOTOPIC EXCHANGE IN ACID SOILS AT LOW AND HIGH ADDITIONS OF SOLUBLE PHOSPHATE

Measurements of equilibrium phosphate concentrations, adsorbed phosphate and isotopically exchangeable phosphate (E_t) were made on suspensions of acid soils at initial P concentrations ranging from 1–1000 μM and pH values between 4.2 and 6.8. At low P concentrations (1–100 μM), the affinity of the adsorption reaction was greatest at pH 5.2–5.5. This result, which was inconsistent with the ligand-exchange hypothesis of Kingston et al. (1967, 1972, 1974), was interpreted in terms of the formation of basic aluminium phosphates of varying composition that depended on the OH/P ratio in solution. At the highest P concentrations (1000 μM), when the affinity of adsorption was least at pH 5.2–5.5, it appeared that basic calcium phosphates were precipitating at pH values > 5.5. In suspensions containing 1–100 μM P initially, values of E_t did not change consonantly with values of adsorbed P over the pH range 4.8 to 5.5. It is suggested that the E_t values were underestimated due to the presence of labelled complexes in solution which were detected by scintillation counting but not by the analysis for orthophos-phate. Evidence from solution studies (White et al., 1976) suggested that as much as one-third of the phosphate could be complexed with aluminium in solutions between pH 4.7 and 5.4 at P/A1 mole ratios of 0.075 to 7.5. It was apparent that the interpretation of the physical significance of E values in acid soils is complex and requires careful appraisal of the experimental techniques used.