应用基因重组NcSRS1抗原对新疆部分地区牛（牦牛）新孢子虫病的血清学调查

目的为摸清新疆部分地区牛（牦牛）感染新孢子虫病的情况。方法从阿勒泰市牛场、104团三分牧场牦牛、乌鲁木齐种牛场的随机抽样48头份血清,采用直接酶联免疫吸附反应（direct-ELISA）法进行检测。结果阿勒泰市牛场感染率为53％（9／17）,乌鲁木齐种牛场感染率为0％（0／15）,104团三分牧场牦牛感染率为0％（0／16）,总感染率为18．8％（9／48）。结论新孢子虫病已经传入新疆地区,应引起人们足够重视,加强防范。     

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.     

Multimammate rat (Mastomys natalensis), Tristram's jird (Meriones tristrami) and Wagner's gerbil (Gerbillus dasyurus) as laboratory models of acute neosporosis

To test the different sensitivity of rodents of the subfamily Murinae and Gerbillinae, Wagner's gerbils (Gerbillus dasyurus), Tristram's jirds (Meriones tristrami) and multimammate rats (Mastomys natalensis) were inoculated with Neospora caninum tachyzoites. Clinical signs of neosporosis appeared in all inoculated animals. Histopathological examination confirmed the presence of tachyzoites in brains, lungs, skeletal muscle, myocardium, liver, in serosa of stomach and intestines, and in vesicular accessory genital glands. An examination of brains by PCR revealed presence of N. caninum DNA in all experimentally N. caninum infected rodents. The susceptibility of Wagner's gerbils and Tristram's jirds further proved the high sensitivity of gerbiline rodents to the N. caninum infection. The finding of N. caninum tachyzoites in the vesicular accessory genital glands of the infected gerbils suggests the usefulness of the rodent model for demonstration of N. caninum in the male reproductive system. Moreover, the multimammate rat was a susceptible experimental host to be the first immunocompetent rodent of the subfamily Murinae.     

Prevalence of Neospora caninum and Toxoplasma gondii in sheep and dogs from Guarapuava farms, Paraná State, Brazil

Sheep and dog blood samples were collected from nine farms in the county of Guarapuava, Paraná, Brazil. The indirect fluorescent antibody test (IFAT) was used to detect Neospora caninum and Toxoplasma gondii antibodies. Herein, serum samples from 305 sheep were evaluated, being 29 (9.5%) and 157 (51.5%) seropositives to N. caninum and T. gondii, respectively. Seven (29.1%) and five (20.8%) out of 24 dogs were seropositives to N. caninum and T. gondii, respectively. There were no differences among the sheep serology for N. caninum and reproductive problems, management and animal feeding variables, neurological problems and presence of other animals species on the farm (P>or=0.05). The simultaneous frequency of antibodies between N. caninum and T. gondii was 5.2% in the herds. Age, breed, farm size, semi-intensive activity, mineral salt supplementation, water origin, stage of the pregnancy when reproduction problems occurred, neurological problems in lambs, presence of rodents in the food room and pasture cat access were identified as associated factors for the occurrence of toxoplasmosis in sheep (P<0.05). There were no differences among the seropositivity in dogs for N. caninum and T. gondii and breed, age and sex (P>or=0.05). The present work is the first report on serum prevalence of N. caninum in sheep from the state of Paraná, Brazil.     

Models for experimental infection of dogs fed with tissue from fetuses and neonatal cattle naturally infected with Neospora caninum

Three models were designed to investigate the development and enteroepithelial phase of Neospora caninum in dogs, and to induce oocyst production by the parasite. In the first model, three dogs were fed raw fetal bovine tissue on two occasions. The bovine fetal tissue had been stored at 4 °C for 14 days and 16 days, respectively, and had tested positive for neosporosis using histopathology and immunohistochemistry. In the second model, nine dogs from the beginning of the experiment until euthanasia were fed portions of tissue from bovine fetuses that been stored at 4 °C for between 1 and 2 days. Three fetuses had tested positive for neosporosis using histopathology and immunohistochemistry. In the third model, three dogs were fed pieces of raw tissue from two neonatal calves that had not received colostrum, and which had tested positive for antibodies against N. caninum. The brains of these calves were positive for neosporosis by histopathology and immunohistochemistry. In all three models, none of the dogs excreted oocysts of N. caninum, developed intestinal parasites or seroconverted.     

Studies on Neospora caninum DNA detection in the oocytes and embryos collected from infected cows

Neosporosis is a major cause of abortion in cattle over the world. One of the methods of preventing vertical transmission within the herd is to avoid breeding replacement heifers from infected dams. Another procedure suggested and recommended by the International Embryo Transfer Society (IETS) is embryo transfer (ET) from infected dams into uninfected recipients. Oocytes and embryos taken from seropositive cows were examined for the presence of Neospora caninum DNA. A modified PCR protocol using Np21 and Np6 primers was applied to detect parasite DNA in the samples. The expected 328 bp product was not obtained in oocytes and/or embryos collected from seropositive dams. The results confirmed that transfer of the embryos from seropositive donors into seronegative recipients is an appropriate method to eliminate vertical transmission of neosporosis in a herd. The present study demonstrated that oocytes and embryos are not exposed to N. caninum in the uterine cavity of seropositive dams.     

用重组蛋白 NcSAG1t作为ELISA诊断抗原进行改良绒山羊Neospora caninum的血清学诊断

N caninum；NcSAG1t；ELISA；改良绒山羊；抗体     

青海省海西地区山羊和绵羊犬新孢子虫病的血清学调查

用犬新孢子虫的重组蛋白GST-NcSAG1t作为ELISA诊断抗原,进行了青海省海西地区山羊和绵羊群中犬新孢子虫病的血清学调查。经过对所收集的120份绵羊血清和531份山羊血清抗体的检测,共检出绵羊阳性血清10份,山羊阳性血清36份,其阳性率分别为8.33%和6.78%。说明青海省海西地区的绵羊和山羊群中存在犬新孢子虫的感染。