Effects of Chlorhexidine Diacetate and Povidone-lodine on Wound Healing in Dogs

To correlate the results of an in vitro study with clinical response, the effects of 0.005 and 0.05% chlorhexidine diacetate and 0.1 and 1.0% povidone-iodine concentrations on wound healing were evaluated in five beagle dogs. Full-thickness skin wounds (2 X 2 cm) were irrigated once daily for 14 days with the antiseptic solutions or physiologic-buffered saline. Chlorhexidine diacetate 0.05% had significantly more bactericidal activity than povidone-iodine and saline, and both chlorhexidine diacetate concentrations had residual effects 6 hours after irrigation. Neither povidone-iodine nor saline had significant bactericidal activity. The percentages of unhealed wound area and wound contraction were calculated 7, 14, and 21 days after wounding. Healed wound area and contraction were similar in wounds treated with chlorhexidine diacetate and povidone-iodine. However, wounds treated with chlorhexidine diacetate had more healed wound area on days 7 and 14 and more contraction on days 7, 14, and 21 than saline-treated wounds. At the concentrations tested, chlorhexidine diacetate irrigations provided bactericidal activity and were more beneficial to wound healing than irrigations with saline alone. These results suggest that concentrations of chlorhexidine diacetate which are cytotoxic to tissue culture fibroblasts in vitro do not interfere with wound healing in vivo.     

The bacteriological and clinical assessment of a new preparation for the treatment of otitis externa in dogs and cats

The efficacy of a preparation (Oterna—Glaxo Laboratories Ltd) for use in the treatment of otitis externa in small animals has been assessed bacteriologically. The aetiology of the disease was studied in 133 ears of cats and dogs; normal ears were examined by comparison. Pityrosporum canis and staphylococci were the organisms most commonly isolated; their incidence was much higher in clinically affected ears than in normal ears. Gram-negative organisms were found only in diseased ears. Seventy-three clinical cases of otitis in dogs and cats were treated with a preparation containing neomycin, monosulfiram and betamethasone. Bacteriological and clinical evaluations were made before and after treatment and the organisms isolated were tested for sensitivity to the antimicrobial constituents of the preparation. There was a 92 % correlation between the bacteriological and clinical results. A ‘good’ or ‘very good’ bacteriological response was recorded for 71% of the ears treated. Résumé. On a évalué bactériologiquement l'efficacité d'une préparation (Oterna—Glaxo Laboratories Ltd) pour l'usage dans le traitement de l'otite externe de petits animaux. L'étiologie de la maladie a été étudiée dans 133 oreilles de chats et chiens; des oreilles normales ont été examinées pour comparaison. Le Pityrosporum canis et des staphylocoques ont été les microorganismes le plus souvent isolés; leur incidence était beaucoup plus élevée dans les oreilles affectées cliniquement que dans les oreilles normales. Des micro-organisms Gram-négatifs ont été seulement trouvés dans les oreilles malades. Soixante-treize cas cliniques d'otite chez les chats et les chiens ont été traités avec une préparation contenant de la néomycine, du monosulfiram et du bétaméthazone. Les évaluations bactériologique et clinique ont été faites avant et après le traitement et les micro-organismes isolés ont été vérifiés pour la sensibilité aux constituants antimicrobiens de la préparation. Il y avait une corrélation de 92% entre les résultats bactériologiques et cliniques. On a enregistré une réaction bactériologique ‘bonne’ ou ‘très bonne’ dans 71% des oreilles traitées. Zusammenfassung. Die Wirksamkeit eines Präparats (Oterna—Glaxo Laboratories Ltd) für die Behandlung von äußerer Otitis bei kleinen Tieren ist bakteriologisch bestimmt worden. Die Ursachenforschung dieser Krankheit wurde an 133 Ohren von Katzen und Hunden durch-geführt. Zum Vergleich wurden normale Ohren untersucht. Pityrosporum canis und Staphylokokken waren die am häufigsten abgesonderten Lebewesen. Ihr Vorkommen war bei klinisch betroffenen Ohren viel größer als bei normalen Ohren. Gram-negative Lebewesen wurden nur in kranken Ohren vorgefunden. Dreiundsiebenzig klinische Fälle von Otitis bei Hunden und Katzen wurden mit einem Präparat behandelt, das Neomycin, Monosulfiram und Betamethasone enthielt. Bakteriologische und klinische Bewertungen wurden vor und nach Behandlung durchgeführt, und die abgesonderten Lebewesen wurden auf Empfindlichkeit gegen mikrobenbetreffende Bestandteile des Präparates geprüft. Zwischen den bakteriologischen und klinischen Ergebnissen bestand eine 92 prozentige Wechselbeziehung. Eine “gute” oder “sehr gute” bakteriologische Reaktion wurde an 71% der behandelten Ohren festgestellt.     

Simulated carrying capacities of fish in Norwegian fjords

The influence of oceanographic and meteorological conditions and topography on the carrying capacity of organisms in coastal areas of western Norway is investigated by field studies and dynamic modelling. Published data on Calanus finmarchicus , the dominant species in the zooplankton biomass of west Norwegian coastal waters, demonstrate a strong gradient, with high densities at the outer coastal areas and lower densities at the innermost localities. This gradient spans several orders of magnitude. A similar tendency is found in the data from pelagic trawling and from beach seine catches, and simulation modelling indicates that fish production depends on zooplankton availability. According to the model, the carrying capacity level of fish production is high in the outer areas and decreases with distance from the outer coast according to the decrease in advected biomass of zooplankton. The simulations indicate that while growth prospects for individuals at lower trophic levels vary with the distance from the coast, potential for growth seems largely unaffected by the distance from the coast for the sublittoral piscivores (e.g. cod). This indicates that, for immigration of a new sublittoral piscivore to a habitat, it does not matter whether the habitat is situated close to the outer coast or far from it. A consequence for stock enhancement may be that a small-scale release of sublittoral piscivores will be equally productive in most coastal areas, while the outcome of a large-scale release will be strongly dependent on distances from the coast. The outcome may be high, but variable, in the outer areas and low, but probably more constant in the innermost areas, provided that releases of juvenile, sublittoral, piscivorous fish do not result in a fish stock density in excess of the carrying capacity level.     

Contributions of FOCI research to forecasts of year-class strength of walleye pollock in Shelikof Strait, Alaska

NOAA's Fisheries Oceanography Coordinated Investigations (FOCI) contributes information to help forecast year-class strength of walleye pollock (Theragra chalcogramma ) in the Gulf of Alaska. Quantitative estimates of recruitment are obtained from models of stock assessment and stock projection employing information supplied by FOCI. To generate its information, FOCI convenes specialists in marine biology, physical and fisheries oceanography, meteorology, and statistics to assemble and analyse relevant biological and physical time series with respect to recruitment and processes hypothesized to influence fish survival. Statistical methods encompass linear and nonlinear regression, stochastic simulation modelling, transfer function time series modelling, and tree-modelling regression. The current database consists of 31 years of data, and analyses have identified factors that affect ocean stratification and circulation during spring and summer of the fish's birth year as being important to recruitment. A conceptual model of the recruitment process serves as the framework for a recruitment forecast scheme. A stochastic mathematical simulation model of the conceptual model produces similarities between simulated and observed recruitment time series. FOCI has successfully forecast recruitment observed over the past several years.