Canine Cutaneous Neosporosis: Clinical Improvement with Clindamycin

Résumé— Une dermite pyogranulomateuse provoquée par le protozoaire Neospora caninum a été diagnostiquée chez un Golden Retriever de 12 ans. Le nombreux nodules fistulisés étaient localisés au niveau de la tête et du thorax. De nombreux tachyzoites de N. caninum ont été retrouvés dans les biopsies des nodules et le diagnostic a été confirmé pas immunohistologie et examen en microscopie électronique. Le chien avait un titre de sérologie Neospora caninum de 3200 par immunofluorescence indirecte. Après un traitement à base de clindamycine pendant 45 jours, les lésions cutanées ont disparu. Le chien est probablement mort à cause d'un lymphosarcome. Il existait aussi une infection latente àToxoplasma gondii. les Neospora caninum n'ont pas pu être retrouvés par des techniques biologiques ni en culture ou par inoculation de souris à partir de prélèvements nécropsiques. Seuls des tachyzoites dégenérés ont pu être observés histologiquement. Ces observations montrent que la néosporose peut être envisagée dans le diagnostic différentiel des dermites pyogranulomateuses du chien et que la clindamycine est un médicament efficace pour traiter la néosporoe canine. [Dubey, J. P., Metzger, F. L., Hattel, A. L., Lindsay, D. S., Fritz, D. L. Canine cutaneous neosporosis: clinical improvement with clindamycin (Néosporose cutanée canine: amélioration clinique par la clindamycine). Resumen— Se diagnosticó una dermatitis piogranulomatosa causada por el protozoo parásito Neospora caninum en un perro de raza Golden Retriever de 12 años. El animal presentaba varios nódulos en la piel de la cabeza y tórax. Se observaron numerosos taquizoitos de N. caninum en los cortes histológicos de tejido obtenido mediante biopsia de dichos nódulos y el diagnóstico fue confirmado por tinción inmunohistológica y por microscopia electrónica. El perro mostró un titulo de anticuerpos contra N. caninum de 1:3,200 en la prueba de fluorescencia indirecta. Las lesiones cutáneas se resolvieron tras un tratamiento con hidroclorido de clindamicina durante 45 dias. El perro murió posteriormente a causa de un linfoma y presentaba también una infestación latente por Toxoplasma gondii. No se pudo demostrar la presencia de Neospora caninum mediante bioensayos en cultivos celulares ni en ratones inoculados con tejido canino obtenido en la necrospia. Tan solo se pudieron observar taquizoitos degenerados de N. caninum en tejido cutáneo obtenido en la necrospia. Estos hallazgos indican que se debe incluir neosporosis en el diagnóstico diferencial de dermatitis piogranulomatosas en el perro y que la clindamicina puede ser un fármaco eficaz para el tratamiento de la neosporosis cutánea. [Canine cutaneous neosporosis: clinical improvement with clindamycin (Neosporosis cutánea canina: mejora clinica con clindamicina). Abstract— Pyogranulomatous dermatitis caused by the protozoan parasite Neospora caninum was diagnosed in a 12-year-old Golden Retriever dog. Multiple draining nodules were located in the skin of the head and thorax. Numerous tachyzoites of N. caninum were found in histologic sections of the biopsy tissue from the cutaneous nodules and the diagnosis was confirmed by immunohistochemieal staining and by electron microscopic examination. The dog had a 1:3200 serum antibody titer to N. caninum in the indirect fluorescent antibody test. The cutaneous lesions resolved after a 45-day treatment with clindamycin hydrochloride. The dog eventually died because of lymphosarcoma and also had a latent infection with Toxoplasma gondii. Neospora caninum could not be demonstrated by bioassays in cell culture or mice inoculated with canine tissue obtained at necropsy. Only degenerating N. caninum tachyzoites were seen in skin tissue taken at necropsy. These observations indicate that neosporosis should be considered in the differential diagnosis of pyogranulomatous dermatitis in dogs and that clindamycin may be an effective drug for treating cutaneous neosporosis.     

Inherited progressive spinal myelinopathy in Murray Grey cattle

In a breeding experiment conducted to determine the mode of inheritance of progressive spinal myelinopathy, semen from a Murray Grey bull which had previously sired affected calves was used to inseminate 120 cows. Female progeny were then inseminated with semen from the same bull. Of the 51 calves born, six (11.8%) had spinal cord lesions consistent with progressive spinal myelinopathy. From analysis of pedigrees and the results of the breeding experiment it was concluded that the condition was inherited as an autosomal recessive condition in Murray Grey cattle.     

Predicting the vertical profiles of anchovy (Engraulis mordax) and sardine (Sardinops sagax) eggs in the California Current System

Several published models exist for simulating vertical profiles of pelagic fish eggs, but no one has rigorously assessed their capacity to explain observed variability. In this study, we applied a steady‐state model, with four different formulations for vertical diffusivity, to northern anchovy (Engraulis mordax) and Pacific sardine (Sardinops sagax) eggs in the California Current region. Vertical mixing profiles, based on wind speed and hydrography, were combined with estimated terminal ascent velocities of the eggs based on measurements of egg buoyancy and size, to simulate the vertical profiles of the eggs. We evaluated model performance with two data sets: (1) vertically stratified tows for both species and (2) paired samples for sardine eggs from 3‐m depth and in vertically integrated tows. We used two criteria: whether the model predicted individual observed vertical profiles (1) as well as the observed mean and (2) better than the observed mean. Model predictions made with the formulation producing the most gradual profile of vertical diffusivity provided the best match to observations from both data sets and for both species. Addition of a random error term to the terminal ascent velocity further improved prediction for anchovy eggs, but not sardine. For the paired data, model prediction of integrated abundance from abundance at 3‐m depth had significantly lower mean square error than prediction based on a linear regression of 3 m on integrated abundance. Our results support the feasibility of using data from the Continuous Underway Fish Egg Sampler quantitatively as well as qualitatively in stock assessments.     

Incidental catch and discard of red drum, Sciaenops ocellatus, in a large mesh Paralichthyidae gillnet fishery: experimental evaluation of a fisher's experience at limiting bycatch

Abstract  The ability of a commercial fisher to limit red drum, Sciaenops ocellatus (Linnaeus), bycatch was evaluated by comparing the catch of directed sets (net site chosen by the commercial fisher) vs randomly placed gillnets during 70 days of gillnetting ( n  = 691 sets). Catch rate did not differ between directed sets and nets set randomly. Thus, fisher experience did not lead to reduced bycatch; however, this may have been influenced by overall low red drum bycatch (0.41 fish net⁻¹ for 12 h sets and 0.59 fish net⁻¹ for 24 h sets). Catch rates of southern flounder were much higher at 3.97 and 3.37 fish net⁻¹ for 12 h and 24 h sets, respectively. Fishing 10 nets per day, the catch of red drum exceeded the daily bag limit of seven red drum on 23% of the days. Of the 326 red drum retrieved from gillnets, 32.5% were dead at the time of retrieval; but only 15 of the 106 dead red drum had to be discarded due to size limits, and six were discarded dead based on bag limits. Current fisheries management regulations (bag limit and window limit of 457–686 mm) are supported by these findings given the conditions (e.g. red drum densities) at which the study was performed.     

Aetiology of an ulcerative disease in goldfish, Carassius auratus (L.): characterization of the causative agent

Abstract. A bacterium resembling Aeromonas salmonicida and determined to be the aetiologic agent of a cutaneous ulcerative disease in goldfish Carassius auratus (L.) was further characterized in this study.
Forty-five isolates of the bacterium (43 from the United States and one each position (moles % guanine plus cytosine) and DNA homology. The bacteriological atypical A. salmonicida previously described. Several important biochemical characteristics distinguished the goldfish isolates from typical A. salmanicida , but the DNA binding experiments indicated a high degree of relatedness between the goldfish isolates and typical A. salmonicida strains.     

A Trial to Cryopreserve Immature Medaka (Oryzias latipes) Oocytes after Enhancing Their Permeability by Exogenous Expression of Aquaporin 3

Fish oocytes have not been cryopreserved successfully, probably because it is difficult to prevent intracellular ice from forming. Previously, we have shown in medaka that immature oocytes are more suitable for cryopreservation than mature oocytes or embryos, in terms of permeability. We have also shown in immature medaka oocytes that the exogenous expression of aquaporin 3 (AQP3), a water/cryoprotectant channel, promotes the movement of water and cryoprotectants through the plasma membrane. In the present study, we attempted to cryopreserve immature medaka oocytes expressing AQP3. We first examined effects of hypertonic stress and the chemical toxicity of cryoprotectants on the survival of the AQP3-expressing oocytes. Exposure to hypertonic solutions containing sucrose decreased the survival of oocytes, but the expression of AQP3 did not affect sensitivity to hypertonic stress. Also, AQP3 expression did not markedly increase sensitivity to the toxicity of cryoprotectants. Of the four cryoprotectants tested, propylene glycol was the least toxic. Using a propylene glycol-based solution, therefore, we tried to cryopreserve immature oocytes by vitrification. During cooling with liquid nitrogen, all intact oocytes became opaque, but many AQP3-expressing oocytes remained transparent. This indicates that the expression of AQP3 is effective in preventing intracellular ice from forming during cooling. During warming, however, all the AQP3-expressing oocytes became opaque, indicating that intracellular ice formed. Therefore, the dehydration and permeation by propylene glycol were still insufficient. Further studies are necessary to realize the cryopreservation of fish oocytes.     

An hypothesis for the aetiology of canine chemoreceptor system neoplasms, based upon an epidemiological study of 73 cases among hospital patients

Of 250, 000 dogs seen by twelve United States and Canadian veterinary-college hospital/clinics, seventy-three dogs were identified with chemo-dectomas. The Boxer and Boston Terrier breeds had significantly higher risk for the tumour than all breeds combined; excessive risk was detected in all male dogs combined and in male dogs 10 years of age and older- especially in Boston Terriers. A familial predisposition aggravated by chronic hypoxia are suggested as possible aetiological factors responsible for the excessive risk in bulldog breeds.