A review of the general pharmacology of ketamine and its clinical use for injectable anaesthesia in horses

Ketamine is the most commonly used injectable anaesthetic in horses. Combinations of ketamine have been used to produce short durations of anaesthesia or as total intravenous anaesthesia (TIVA) for longer diagnostic or surgical procedures. In recent years, ketamine has been used for pain management due to its effectiveness in producing analgesia at subanaesthetic doses. This paper provides a review of the pharmacological effects of ketamine in general and its clinical use for injectable anaesthesia and pain management in horses.     

A review of equine rectal tears and current methods of treatment

Rectal tears are a risk of rectal palpation during equine clinical examination and can be life‐threatening; prompt medical and surgical intervention is required to improve patient outcome. Depending on the degree of the tear, conservative treatment or surgical management may be warranted. Surgical management involves either direct suturing or faecal diversion techniques, such as colostomy or a temporary indwelling rectal liner. The prognosis for a horse with a rectal tear depends on size of the tear, grade and location of the tear, and time between occurrence and first aid measures.     

Management of apposing,full‐thickness tracheal perforations in two horses

Two horses, one 15‐year‐old Arabian gelding and one 10‐year‐old Quarter Horse gelding, presented with a history of marked subcutaneous emphysema. The first case exhibited no external wound, although there was a depression noted on the ventral neck. The second case had a laceration on the ventral aspect of the neck over the trachea. Endoscopic examination revealed both horses to have concurrent dorsal and ventral perforations of the trachea. The horses were managed by placing a short, cuffed, J‐shaped tracheostomy tube in the ventral perforation, while the dorsal perforation healed. The dorsal perforation in the first horse was allowed to heal by second intention, whereas sutures were placed in the dorsal perforation in the second case to reduce the healing time. Both horses were maintained on oral antimicrobial and nonsteroidal anti‐inflammatory medications throughout treatment. The dorsal perforation healed after 13 days in the first horse, and 22 days in the second horse. The ventral perforation healed in both horses by second intention following tracheostomy removal, giving a cosmetically acceptable result. In addition to facilitating tracheal healing, the tracheostomy tubes prevented the progression of subcutaneous emphysema, and promoted its resolution.     

Solid waste management in Santa Barbara county

Santa Barbara County commenced to modernize its solid waste system in 1960 by passage of an ordinance by the Board of Supervisors assuming the responsibility for waste disposal and regulation of refuse collection. Private collectors were licensed, with collection service, equipment and rates controlled by the County. Transfer facilities were put in service in the populous south coast area in 1967 with a sanitary fill site planned to become a future recreation area. After several years of operation, costs of transfer and disposal are four dollars per ton. Although totally funded by the County plus revenues up to this year, the refuse disposal operation became an ‘enterprise fund’ on July 1, 1974 and will thereafter operate essentially as a private business. Financial planning for refuse disposal in Santa Barbara County has assumed continuation of the sanitary fills and transfer system until 1980, but the new Solid Waste Management Plan for the County now required by the State will evaluate resource recovery, power generation and other possible alternatives. Based on these studies, the plan may lead to a new phase in improvement of solid waste management in the County.     

Effect of elevated manganese on the ultraviolet‐ and blue light‐absorbing compounds of cucumber cotyledon and leaf tissues

The effect of manganese [Mn(II)] on the pigments of cucumber (Cucumis sativus L., cv Poinsett 76) leaf and cotyledon tissues was investigated. Tissue disks (7 mm) were exposed to increasing Mn(II) concentrations from 100 μM to 2.5 mM. Acetone (carotenoid‐rich fraction) and acidified methanol (flavonoid‐rich fraction) extracts were analyzed by high performance liquid chromatography. Although none of the Mn(II)‐treated tissues showed visible damage, Mn(II) at concentrations of 250 μM and above significantly reduced (60%) the ß‐carotene levels of light‐incubated leaf tissues. A major Mn(II)‐induced, UV‐absorbing compound was observed in methanol extracts of cotyledonary tissues exposed to Mn(II) in the dark. In leaf tissues, Mn(II) reduced the levels of certain UV‐absorbing compounds under both light conditions. These results demonstrate that excess leaf Mn(II) can rapidly impair isoprenoid metabolism, altering tissue carotenoid composition. Furthermore, Mn(II) may also modify phenylpropanoid metabolism, changing the tissue flavonoid composition. Both situations could sensitize plant tissues to oxidative stresses, particularly enhanced solar UV‐B radiation, and may reduce the nutritional quality of leafy vegetables.     

End Product Quality and Agronomic Performance of Compost

Washington State University produces a manure-based compost of high pH (>8) and low N content (1 percent) by windrow composting campus wastes. Annual production at the four-acre facility is 18-20,000 cubic yards. In the interest of producing compost of higher N content and lower pH, ten experimental piles were constructed to investigate the effects of different feedstocks on the composting process, end quality and agronomic performance. Biosolids and manure were compared at two rates of bedding both with and without coal ash. Compost temperature and inorganic N content during 96 days of active composting are reported along with end product nutrient analysis and metal concentration. The composts behaved differently based on the N feedstock and level of bedding in the mix. Compost quality was influenced by the characteristics of the feedstocks. Applying the composts to an eroded hilltop (50 Mg/ha) increased winter wheat yield, but there were no differences among the ten composts.     

Production and Interior Performances of Tropical Ornamental Foliage Plants Grown in Container Substrates Amended with Composts

Three representative Florida composts were mixed by volume with sphagnum peat and pine bark to formulate 12 container substrates. After physical and chemical characterization, the substrates, along with a control, were used to grow containerized Cordyline terminalis ‘Baby Doll’, Dieffenbachia maculata ‘Camille’, and Dracaena fragans ‘Massangeana’ cane. All substrates were able to produce marketable plants, but only five or seven, depending on plant genus, of the 12 compost-formulated substrates resulted in plants comparable or superior to those of the control substrate. The five also had substrate shrinkage equal to or less than the control. Plants were then moved to an interior evaluation site to determine the suitability of compost-formulated substrates in sustaining foliage plant growth under an interior environment. During a six-month interior evaluation, the plants maintained their aesthetic appearances. Based on plant growth parameters and quality ratings as well as substrate shrinkage both in production and interior evaluation, five of 12 compost-formulated substrates were identified to be equal or superior to the control. This study showed that the three composts, after being appropriately mixed with sphagnum peat and pine bark, can be used as container substrates in every phase of tropical foliage plant production and utilization.     

Thresholds in seascape connectivity: influence of mobility, habitat distribution, and current strength on fish movement

Assessing connectivity of the marine environment is a fundamental challenge for marine conservation and planning, yet conceptual development in habitat connectivity has been based on terrestrial examples rather than marine ecosystems. Here, we explore differences in marine environments that could affect localized movement of marine organisms and demonstrate the importance of incorporating them into seascape models. We link a fish-based cost surface model to simulated seascapes to test hypotheses about the effects of fish mobility, water current strength, and their interactions on functional connectivity of a seascape. Our models predict that sedentary fish should be more sensitive to habitat change than more mobile fish. Furthermore, highly mobile fish should be more sensitive to water currents than habitat change. In our models, the cost of swimming against a current (of any strength) exceeded its benefits, resulting in overall decreases in connectivity with increasing current strengths. We further hypothesized that thresholds in functional connectivity will be affected by both fish mobility and water current strength. Connectivity thresholds in the models occurred when 10–50 % of benthic habitat was favourable; below these thresholds there was a rapid increase in path cost. Thresholds were influenced by the interaction of relative habitat costs (simulated fish mobility) and habitat fragmentation: thresholds for less mobile fish (higher relative cost) were reached at lower habitat abundance when habitat was fragmented, while thresholds for mobile fish were less affected by fragmentation. Our approach suggests mobility and water current are useful indicators of connectivity in marine environments and should be incorporated in seascape models.     

Absorption, disposition, metabolism, and excretion of [3-(14)C]caffeic acid in rats

Male Sprague-Dawley rats ingested 140 × 10(6) dpm of [3-(14)C]trans-caffeic acid, and over the ensuing 72 h period, body tissues, plasma, urine, and feces were collected and the overall levels of radioactivity determined. Where sufficient radioactivity had accumulated, samples were analyzed by HPLC with online radioactivity and tandem mass spectrometric detection. Nine labeled compounds were identified, the substrate and its cis isomer, 3'-O- and 4'-O-sulfates and glucuronides of caffeic acid, 4'-O-sulfates and glucuronides of ferulic acid, and isoferulic acid-4'-O-sulfate. Four unidentified metabolites were also detected. After passing down the gastrointestinal tract, the majority of the radiolabeled metabolites were excreted in urine with minimal accumulation in plasma. Only relatively small amounts of an unidentified (14)C-labeled metabolite were expelled in feces. There was little or no accumulation of radioactivity in body tissues, including the brain. The overall recovery of radioactivity 72 h after ingestion of [3-(14)C]caffeic acid was ～80% of intake.     

The Influence of Bioactive Oxylipins from Marine Diatoms on Invertebrate Reproduction and Development

Diatoms are one of the main primary producers in aquatic ecosystems and occupy a vital link in the transfer of photosynthetically-fixed carbon through aquatic food webs. Diatoms produce an array of biologically-active metabolites, many of which have been attributed as a form of chemical defence and may offer potential as candidate marine drugs. Of considerable interest are molecules belonging to the oxylipin family which are broadly disruptive to reproductive and developmental processes. The range of reproductive impacts includes; oocyte maturation; sperm motility; fertilization; embryogenesis and larval competence. Much of the observed bioactivity may be ascribed to disruption of intracellular calcium signalling, induction of cytoskeletal instability and promotion of apoptotic pathways. From an ecological perspective, the primary interest in diatom-oxylipins is in relation to the potential impact on energy flow in planktonic systems whereby the reproductive success of copepods (the main grazers of diatoms) is compromised. Much data exists providing evidence for and against diatom reproductive effects; however detailed knowledge of the physiological and molecular processes involved remains poor. This paper provides a review of the current state of knowledge of the mechanistic impacts of diatom-oxylipins on marine invertebrate reproduction and development.