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21.
An 18-month-old neutered male Rottweiler was examined because of slowly progressive spastic tetraparesis and ataxia. Signalment and clinical signs were suggestive of 2 neuronal degenerative diseases presumed to be inherited in young Rottweilers: leukoencephalomyelopathy and neuroaxonal dystrophy. Myelography revealed an extradural compression at the articulation of the second and third cervical vertebrae. At surgery, focal hypertrophy of the yellow ligament was observed to compress the spinal cord ventrally at that site.  相似文献   
22.
Three doses of sodium monoiodoacetate (MIA) were used to induce degenerative changes in articular cartilage in middle carpal joints of horses. Twelve young (2- to 5-year-old) horses, free of lameness, were randomly allotted to 3 groups. One middle carpal joint of each horse was injected with 0.9% NaCl solution (control joint). The contralateral middle carpal joint was injected with 0.09 mg of MIA/kg of body weight (group 1); 0.12 mg/kg (group 2); or 0.16 mg/kg (group 3). After MIA administration, horses were allowed ad libitum exercise in a 2-acre paddock for 12 weeks. At the end of the study, gross and microscopic tissue changes were evaluated and biochemical analyses of articular cartilage were done. Grossly, diffuse partial-thickness articular cartilage lesions were observed in group-2 (n = 2) and group-3 (n = 4) horses, but not in group-1 horses. Articular cartilage uronic acid content was significantly (P less than 0.03) decreased in all MIA-injected joints, compared with controls. Articular cartilage matrix staining with safranin-O was decreased in 3 of 4 MIA-injected joints of group-1 horses and in all MIA-injected joints of group-2 and group-3 horses, compared with controls (P less than 0.06). Microscopic degenerative changes in articular cartilage were not significantly different between MIA-injected and control joints in group-1 horses, but were increased (P less than 0.06) in all MIA-injected joints of group-2 and group-3 horses, compared with controls. Qualitatively, decreased matrix staining and degenerative changes were more severe in group-3 horses. On the basis of articular cartilage gross and microscopic changes, as well as biochemical changes, 0.12 mg of MIA/kg injected intra-articularly was determined to induce moderate degrees of articular cartilage degeneration. This model of chemically induced articular cartilage injury could be useful for evaluating treatment effects of anti-arthritic drugs in horses.  相似文献   
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24.
Influence of nonbiologic implants on laminectomy membrane formation in dogs   总被引:1,自引:0,他引:1  
The effects of various surgical implants, spinal cord hypothermia, and glucocorticoid administration on formation of the laminectomy membrane were evaluated in 32 preconditioned chondrodystrophoid dogs. Modified dorsal laminectomies and full-length durotomies, from T12 to L1, were performed on all dogs. Dogs were allotted to 2 groups. Group-1 dogs (n = 20) were further allocated to 4 subgroups (a, b, c, and d) consisting of 5 dogs each. Group-1a dogs received no implant, group-1b dogs had absorbable gelatin sponges implanted, group-1c dogs had absorbable gelatin films implanted, and group-1d dogs had absorbable gelatin sponges and absorbable gelatin films implanted. Daily neurologic examinations permitted correlation of neurologic dysfunction with secondary spinal cord compression in those dogs in which it developed. The influence of these implants on laminectomy membrane formation and dural healing was assessed by gross and microscopic evaluation of transverse sections of the vertebrae and spinal cord after euthanasia of one member of each subgroup at 1, 2, 4, 8, and 16 weeks after surgery. Group-2 dogs (n = 12) were further allotted to 3 subgroups (a, b, and c) consisting of 4 dogs each. One dog in each group-2 subgroup underwent the same surgical procedures described for the group-1 subgroups (ie, 4 procedures/group-2 subgroup). The additional effects of 3 conventional supportive techniques (selective regional spinal cord hypothermia, glucocorticoid administration, or spinal cord hypothermia and glucocorticoid administration) on laminectomy membrane formation and on immediate postoperative recovery were examined in groups 2a, 2b, and 2c, respectively. Neurologic examinations were performed daily until this time. All dogs in group 2 were euthanatized 1 week after surgery for gross and microscopic examination of transverse sections of the vertebrae and spinal cord. Qualitative histopathologic effects of the different implants and supportive techniques on formation of the laminectomy membrane were determined. Statistical analysis of the degrees of secondary spinal cord compression was performed in group-1 dogs by measuring and comparing ratios of the vertical to the horizontal diameters of the transverse spinal cord sections from locations within (T12 to L1) and out of (T11, T11-12, L1-2, and L2) the region of surgical intervention. The vertical/horizontal diameter ratios measured from transverse sections from T11 to L2 in size-matched, untreated control dogs formed the standards for a mean roundness index of the spinal cord in the various anatomic locations of the vertebral column.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
25.
Arthroscopic surgery for the treatment of osteochondritis dissecans was undertaken on 252 femoropatellar joints in 161 horses (82 Thoroughbreds, 39 Quarter Horses, 16 Arabians, 9 Warmbloods and 15 others of various breeds). There were 53 females and 108 males. Twenty-two horses were 1 year of age at the time of surgery, 68 were yearlings, 36 were 2-year-olds, 21 were 3-year-olds, and 14 were > or = 4 years old. Ninety-one had bilateral involvement and 70 had unilateral disease. Follow-up information was obtained on 134 horses, including 79 racehorses and 55 non-racehorses: 86 (64%) of these 134 horses returned to their intended use, 9 (7%) were in training, 21 (16%) were unsuccessful and 18 (13%) were unsuccessful due to other defined reasons. Horses with Grade I lesions (< 2 cm in length) had a significantly higher success rate (78%) than did horses with Grade 2 (2-4 cm) or Grade 3 (> 4 cm) lesions (63% and 54% success rates respectively). A significantly higher success rate was also noted for horses operated on as 3-year-olds compared with the remainder of the study population. A significantly lower success rate was noted for yearlings than for the remainder of the population. There was no significant difference in outcome as related to sex of animal involved, racehorse versus non-racehorse, lesion location, unilateral versus bilateral involvement, presence or absence of patellar or trochlear groove lesions, or presence or absence of loose bodies.  相似文献   
26.
Surgery for abnormal vulvar and perineal conformation in the mare   总被引:1,自引:0,他引:1  
Reproductive failure in mares can present a challenge to the attending veterinarian. Although many causes of failure to conceive or to carry to term may be easy to diagnose and treat effectively, others may be difficult. In some cases, more than one problem will be present, and both medical therapy and surgical intervention will be required to achieve a successful outcome. Pneumovagina and its sequelae remain a common cause of reproductive failure in mares. Depending on the case involved, different surgical techniques may be required to correct the problem.  相似文献   
27.
As forested systems are impacted by both natural and anthropogenic factors such as climate change, the biodiversity supported by those forests is likely to change. Quantifying that change, however, remains a difficult task due to variations in the sizes and conditions of forested systems. Species accumulation curves are a commonly used tool to scale estimates of species richness and provide an avenue for comparing biodiversity among habitats through rarefaction. However, we found that the ranked biodiversity among forested systems depends on the sample unit used, and there is a need to integrate landscape heterogeneity in spatially scaleable estimates of biodiversity. Both of these biodiversity assessment issues can be addressed using a new approach we term the Integrated Accumulation Function (IAF), a method based on combining component species accumulation curves. Using this approach on communities of canopy arthropods found in pinyon pine forests in the southwestern United States, we found three major patterns. First, in small stands, trees growing under low environmental stress support the greatest species richness. Second, when stands are large, stands growing under higher environmental stress support greater species richness, and species richness is resilient to change over a broad range of the stress gradient. Third, there are threshold levels of stress at both ends of the stress spectrum beyond which species are rapidly lost. This analysis reveals unexpected patterns and suggests that conservation practices should consider the inclusion of forests growing under suboptimal conditions to maximize the preservation of biodiversity.  相似文献   
28.
CASE HISTORY: A 2-year-old female Siberian Husky was presented with a 6-month history of sneezing and mucous discharge from the right nostril.

CLINICAL FINDINGS: Reduced airflow through the right nostril was evident. Radiographs showed subtle loss of detail of turbinates within the right nasal chamber. Rhinoscopy revealed swollen and erythematous turbinates and a white mass within the caudal aspect of the right nasal cavity. Histopathologically, there was a heavy mixed inflammatory infiltrate in the submus- cosa of the right turbinate, and the presence of fungal hyphae and spores in the white mass. A heavy growth of Scedosporium apiospermum was cultured from the mass.

DIAGNOSIS: Chronic rhinitis of the right nasal cavity and infection with S. apiospermum.

CLINICAL RELEVANCE: This is the first reported case of S. apiospermum isolated from the nasal cavity of a dog in New Zealand. Fungal culture is necessary to differentiate this fungus from Aspergillus spp.  相似文献   
29.
CASE HISTORY: A 5-year-old neutered male Cornish Rex cat was presented for evaluation with a history of vomiting over the previous 5 days.

CLINICAL FINDINGS: An abdominal mass was palpated, which was shown to be cystic by ultrasound examination. Exploratory surgery revealed this to be associated with the pancreas and it was duly resected. Histopathology was performed on the cystic mass.

DIAGNOSIS: Pancreatic cyst with associated chronic active infl ammation.

CLINICAL RELEVANCE: This is the first report of a true pancreatic cyst in a cat.  相似文献   
30.
The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes.  相似文献   
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