THE USE OF AMITRAZ IN THE CONTROL OF AN OUTBREAK OF SARCOPTIC MANGE IN A COLONY OF KOALAS

SUMMARY: An outbreak of sarcoptic mange in a colony of koalas was effectively controlled by the topical application of amitraz as a 0.025% aqueous suspension. Several koalas died in the 9 months preceding treatment, with lesions suggestive of Sarcoptes scabiei ; however, no further deaths occurred following treatment and there was complete recovery of all affected animals.     

Orthotopic Osteochondral Transplantation of the Canine Proximal Femur

An 18-week study was conducted to evaluate orthotopic osteochondral transplantation of the proximal femur in the dog. Eighteen dogs were divided into 3 groups of 6 each. The first group received autografts, the second received fresh allografts, and the third received grafts that had been frozen in a bone bank for 24–28 days. The grafts were fixed in position using dynamic compression plates. The grafted limbs were maintained in a sling and thus were nonfunctional and non-weight bearing throughout the 18-week study. Postoperatively the dogs were given oral tetracycline to assess osteo- cyte viability. The dogs were radiographed at 2–week intervals and 1 dog in each group was euthanatized every 3 weeks. The femurs were examined using standard histopathologic and fluorescent labeling techniques. All femoral heads were luxated by the 2nd postoperative week. The bones of all the femoral heads underwent avascular necrosis and degenerative changes were present in the transplanted cartilage by the 6th postoperative week. During the first 18 weeks following transplantation there was little radiographic and histologic difference among the 3 types of grafts regarding the nature and rate of bone healing. Based on the data obtained from techniques utilized in this study, the femoral head, neck, and articular cartilage did not survive, while the femoral diaphysis did survive the transplantation process. Different techniques may alter to some degree the results obtained.     

Radiographic and Histologic Changes After Thoracolumbar Disc Curettage

Forty-eight thoracolumbar disc spaces were approached by a dorsolateral muscle-separating technique in six mature dogs. Twenty-four of the discs were fenestrated and curetted, and the changes were followed radiographically and histologically for 16 weeks. Disc space collapse was visible radiographically immediately after the surgical procedure, and those disc spaces remained narrow throughout the observation period. Histologically, there was evidence of chondrocyte activation within 2 weeks in the excavated disc spaces. By 16 weeks, fibrocartilage had filled the void in the curetted disc spaces.     

Plasma and urine disposition and dose proportionality of ceftiofur and metabolites in dogs after subcutaneous administration of ceftiofur sodium

Nine male dogs (10.3–13.5 kg body weight) were randomly assigned to three groups of three dogs each and administered ceftiofur sodium subcutaneously as a single dose of 0.22, 2.2, or 4.4 mg ceftiofur free acid equivalents/kg body weight. Plasma and urine samples were collected serially for 72 h and assayed for ceftiofur and metabolites (derivatized to desfuroylceftiofur acetamide) using high-performance liquid chromatography. Urine concentrations remained above the MIC ₉₀ for Escherichia coll (4.0 μg/mL) and Proteus mirabilis (1.0 μg/mL) for over 24 h after doses of 2.2 mg/kg (8.1 μg/mL) and 4.4 mg/kg (29.6 μg/mL), the interval between treatments for ceftiofur sodium in dogs, whereas urine concentrations 24 h after dosing at 0.22 mg/kg (0.1 mg/Ib) were below the MIC ₉₀ for E.coli and P. mirabills (0.6 μg/mL). Plasma concentrations were dose-proportional, with peak concentrations of 1.66 ± 0.0990 μg/mL, 8.91 ± 6.42 μg/mL, and 26.7 ± 1.07 μg/mL after doses of 0.22, 2.2, and 4.4 mg/kg, respectively. The area under the plasma concentration versus time curve, when normalized to dose, was similar across all dosage groups.     

Immunocytological confirmation of a diagnosis of canine distemper using cells in urine

Immunofluorescent staining of epithelial cells present in urine of early clinical cases of canine distemper confirmed the presumptive diagnosis by revealing fluorescing intracytoplasmic inclusions. Positive results were not obtained in urine samples from control dogs nor from samples from dogs ill for more than three weeks. The urine samples, with added preservative, still yielded positive results after 5 days storage at 37°C or 21 days storage at 18°C.     

The Effects of Essential Fatty Acid Supplementation on Intradermal Test Reactivity in Atopic Dogs: a Preliminary Study

Abstract— Twenty-one perennially affected atopic dogs with previous intradermal test reactivity to two or more environmental allergens were retested while receiving either a combination of evening primrose oil and fish oil (EfaVet Regular, Efamol Vet) or a concentrated supplement containing gammalinolenic acid and eicosapentaenoic acid (HGF capsules). Significant differences in the mean number of positive reactions before and during therapy were not found. In addition, the mean histamine, Dermatophagoides pteronyssinus and housedust wheal diameters before and during therapy were not significantly different. However, the mean human dander wheal diameter was significantly reduced (P < 0.05) at the second test, and the mean Dermatophagoides farinae wheal diameter was significantly reduced (P < 0.05) in a group of seven dogs which had received long-term essential fatty acid supplementation with HGF capsules. These results indicate that essential fatty acid supplementation does not abrogate but may reduce intradermal test reactivity in atopic dogs. Résumé— Vingt et un chiens atopiques, présentant des symptômes non saisonniers, ayant eu des tests cutanés positifs à au moins un pneumallergène ont été testés alors qu'ils recevaient une association d'huile d'onagre et d'huile de poisson (Efa Vet Regular, Efamol Vet) ou un supplément concentré d'acides gammalinolénique et éicosapentaénoique (capsules HGF). Aucune différence significative dans le nombre moyen de réactions positives avant et après traitement n'a été observée. En outre les diamètres moyens des réactions à l'histamine. Dermatophagoïdes pteronyssinus et la poussère de maison avant et après traitement n'étaient pas significativement différents. Toutefois, le diamètre moyen des réactions aux squames humaines étaient significativement réduits (P < 0,05) lors du second test, et le diamètre moyen des réactions àDermatophagoïdes farinaeétait significativement réduit (P < 0,05) dans un groupe de sept chiens ayant reçu une supplémentation à long terme de capsules HGF. Ces résultate montrent qu'une supplementation en acides gras essentiel n'anihile pas les tests cutanés mais peu modérer la réactivité cutanée chez certains chiens atopiques. Resumen Veintiún perros atópicos de tipo estacional que presentaban reactividad positiva en la prueba de inyacciones intradérmicas con respecto a dos o más alergenos ambientales, fueron sometidos a una segunda prueba recibiendo simultáneamente una combinación de aceite de Evening Primrose y aceite de pescado (Efa Vet Regular, Efamol Vet) o un concentrado que contenía ácidos gammalinoleico y ecosapentanoico (HGF cápsulas). No se encontraron diferencias significativas en la media de las reacciones positivas antes y después de la medicación. Tampoco se encontraron diferencias significativas entre las medidas del diámetro de la roncha producida por la histamina, el Dermatophagoides pteronyssinus y el alergeno del polvo. Sin embargo, la media del diámetro producido por el alergeno de la caspa humana se vió considerablemente reducida en el segundo test (P < 0.05), así como la del Dermatophagoides farinae (P < 0.05) en un grupo de siete perros los cuales recibieron suplementación con ácidos grasos esenciales a largo plato con HGF cápsulas. Éstos resultados indican que el uso de ácidos grasos esenciales no produce supresión de las reacciones positivas del test intradérmico en perros atópicos, pero sí de las mismas.     

Human rhodopsin

Human rhodopsin in aqueous solution has lambda(max). of 493 mmicro and is lower in the spectrum than the rhodopsins of all other known vertebrates, with the exception of certain deep-sea fishes. Its molar extinction is 40,000 +/- 800. Like other rhodopsins, it bleaches to a mixture of opsin and all-trans retinene and is resynthesized by incubating opsin with neo-b (11-cis) retinene. The regenerated rhodopsin has the same lambda(max). as the extracted pigment; this is due, therefore, not to an unusual retinene but to a characteristic human opsin. The regeneration in solution from opsin and neo-b retinene is a second-order reaction with a half-time, at 29.5 degrees C, of about 2.5 minutes. This is much faster than the synthesis of rhodopsin in the living human eye, and faster than human rod dark-adaptation; the rate of both processes in vivo must be limited by reactions which precede the union of neo-b retinene with opsin, the final step in rhodopsin synthesis. In the rods, rhodopsin is virtually in the solid state-highly oriented in close relation with other highly oriented molecules. In this situation its spectrum is displaced toward the red (lambda(max) 500 mmicro) and is narrower than in solution. For light entering the rods axially, rhodopsin has also a considerably increased extinction, some 1.5 times higher than when randomly oriented. The spectrum of rhodopsin in rods agrees well in form and position with the spectral sensitivity of human rod vision, measured at the retinal surface.