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101.
Transplacental Neospora caninum infection in dogs   总被引:3,自引:0,他引:3  
A Beagle bitch was inoculated SC and IM with 1.5 million Neospora caninum tachyzoites on the 35th day of gestation. Eight pups were born alive 28 days after N caninum inoculation of the bitch. Pup 1 did not breathe and died while still enclosed in fetal membranes. Pup 2 died 2 days after birth (DAB). Pups 3, 4, and 5 were euthanatized on 2, 3, and 20 DAB, respectively, because they were hypothermic and not nursing. Pups 6, 7, and 8 remained clinically normal. Indirect fluorescent N caninum serum antibody titers were: less than 50 (pups 1 and 8 at 17 DAB, and the bitch before inoculation), 50 (pups 2 and 3 on 2 DAB), 200 (pups 6 and 7 on 17 DAB), and 800 (bitch on day 17 after parturition). Neospora caninum was recovered in cultured cells inoculated with placenta and tissues from all 5 pups necropsied, and N caninum was seen in histologic sections of the heart of pup 5. Results indicate that N caninum can be transplacentally transmitted in dogs.  相似文献   
102.
Severe necrotizing myelitis secondary to localization and reactivation of Toxoplasma gondii within the spinal cord of a domestic shorthair cat was diagnosed by use of light and electron microscopy and immunohistochemistry. The cat also was infected with feline immunodeficiency virus. This case may have useful comparative features to T gondii infections in human patients with acquired immunodeficiency syndrome.  相似文献   
103.
Sixteen 50 day gestational ewes were fed lasalocid at the rate of 30 g t-1 and were orally inoculated with 100 infective Toxoplasma gondii oocysts 5 days after beginning feeding of lasalocid. Seventeen control ewes were similarly inoculated with T. gondii and were not fed lasalocid. The rate of abortion and neonatal mortality in both treated and untreated ewes was similar, indicating that feeding lasalocid was not effective in preventing T. gondii abortion in sheep.  相似文献   
104.
105.
Immunohistochemical diagnosis of Neospora caninum in tissue sections   总被引:10,自引:0,他引:10  
An avidin-biotin-peroxidase complex immunoperoxidase staining method was developed to detect Neospora caninum in formalin-fixed, paraffin-embedded tissue sections. Specific antiserum to N caninum was made in rabbits and used to probe tissues from dogs naturally and experimentally infected with N caninum. The test detected tachyzoites and bradyzoites of N caninum. A reaction was not observed to Toxoplasma gondii, Hammondia hammondi, Sarcocystis cruzi, S capricanis, S tenella, Besnoitia jellisoni, Caryospora bigenetica, Hepatazoon canis, Atoxoplasma sp, or the organism causing canine dermal coccidiosis. When antiserum made in rabbits to T gondii was used in the test, reaction to N caninum was not observed.  相似文献   
106.
Ovine sporozoan encephalomyelitis linked to Sarcocystis infection   总被引:1,自引:0,他引:1  
The unidentified sporozoan causing encephalomyelitis in sheep described by Hartley and Blakemore (1974) was restudied, and the parasite was identified as a Sarcocystis species based on its location and structure. The parasite was located free in the host-cell cytoplasm, divided by endopolygeny and mature merozoites lacked rhoptries.  相似文献   
107.
Toxoplasmosis   总被引:2,自引:0,他引:2  
  相似文献   
108.
Serum samples from 283 llamas (Lama glama) from Oregon, Washington State and Idaho were tested for antibodies to Toxoplasma gondii using the modified agglutination test. Antibodies were found in 95 (33.5%) llamas. Percent seropositivity in serum dilutions of 1:25, 1:50, 1:500, and 1:5000 was 9.5%, 18.3%, 4.9%, and 0.7%, respectively.  相似文献   
109.
Nineteen does (female goats) were dosed with 500,000 oocytes of Hammondia hammondi prior to breeding. At about 90 days of gestation these, and 18 uninoculated does were challenged with 25,000 Toxoplasma gondii oocysts. The 19 H. hammondi--inoculated does produced 26 live and one dead kid (newborn goat). The 18 does not given H. hammondi produced 12 live and 19 dead kids. However, examination of all of the kids by isolation of T. gondii in mice, serology and histology revealed that they were all infected with T. gondii. Thus, while H. hammondi "vaccination" is protective against the deleterious effects of T. gondii on pregnant does, perhaps by reducing the severity of placental lesions, it does not prevent foetal infection.  相似文献   
110.
Food safety regulations require the control of the presence of protozoa in meats destined for human consumption. Wild boar (Sus scrofa) meat may constitute a source of zoonoses. A 23.8% (688/2881) seroprevalence of anti‐Toxoplasma gondii antibodies and 72.2% (662/910) Sarcocystis sarcocysts prevalence were detected among wild boars hunted in Southwestern areas of Spain. Identity of Sarcocystis spp. was performed by RFLP‐PCR and sequencing, detecting S. miescheriana (7/8) and the zoonotic S. suihominis (1/8). Risk assessment studies of these coccidian in meats destined to human consumption are needed.  相似文献   
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