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An outbreak of Fusobacterium necrophorum-induced septicemia occurred in a group of 40 captive wild-caught pronghorns (Antilocapra americana). Primary pododermatitis or necrotic stomatitis progressed to produce fatal septicemia with metastatic lesions in the forestomachs, lung, liver, and cecum in 38 of the animals. Two remaining animals were euthanatized because of chronic pododermatitis. Housing the animals in a pasture previously used by bovids and heavy rains with persistence of ground water pools in the pasture were contributing factors in the pathogenesis of this outbreak.  相似文献   
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Cross-sectional prevalences and risk factors for Brucella seropositivity in goats in eastern and western Uganda were investigated. Serum was collected from 1518 goats randomly selected from 145 herds which had been identified using multistage sampling. The brucellosis card test (CT) and the Brucella melitensis tube-agglutination test (TAT) were used in parallel to detect antibodies against B. abortus and B. melitensis, respectively. Interviewer-administered questionnaires were used to collect information on goat health and management. This information was used in multivariable logistic-regression models to determine the risk factors for Brucella seropositivity in goat herds. For each analysis, a herd was considered positive if at least one goat in the herd tested positive for antibodies against Brucella and negative if none was positive.Four percent (55/1480) of the goats screened with the CT had antibodies against Brucella. The reactors were distributed in 13% (19/145) of the herds. The most-important herd-level risk factors identified were use of a hired caretaker as the primary manager of the operation compared to owner/family members (adjusted odds ratio (OR)=8.1; 95% CI 1.6, 39.7), keeping sheep in addition to goats (OR=6.0; CI 1.5, 23.7) compared to having no sheep, and free browsing (OR=4.7; 95% CI 1.0, 20.7) when compared to tethering or zero-grazing.Using the TAT, 10% (141/1446) of the goats tested positive. The positives were distributed in 43% (63/145) of the herds. Free browsing (OR=6.7; 95% CI 2.7, 16.9) when compared to tethering or zero-grazing and lack of veterinary care (OR=2.9; CI 1.3, 6.7) were the most-important factors identified in the multivariable model for B. melitensis herd seropositivity.To explore/reduce the risk of misclassification in a secondary analysis, herds were reclassified as positive if at least one goat tested positive on both tests and negative if none of the goats was positive on any of the two tests. Using this classification, 2% (30/1320; 95% CI 2, 3%) of the goats tested positive resulting in 13% (12/93) of the herds being positive. The distribution of the above risk factors by brucellosis herd-status (as defined by the second criterion) is also presented.  相似文献   
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Horses with undescended testes are frequently presented to the veterinary surgeon for castration. The pertinent pre-operative evaluations and diagnostic procedures that should be made prior to either surgical intervention or referral of such cases are outlined. Several accepted anesthetic and surgical techniques are similarly reviewed. Case histories of 58 horses referred during a two year period are reviewed and correlated with the findings of a recent study of equine testicular development and descent.  相似文献   
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Major outer membrane proteins of Brucella spp.: past,present and future   总被引:16,自引:0,他引:16  
The major outer membrane proteins (OMPs) of Brucella spp. were initially identified in the early 1980s and characterised as potential immunogenic and protective antigens. They were classified according to their apparent molecular mass as 36–38 kDa OMPs or group 2 porin proteins and 31–34 and 25–27 kDa OMPs which belong to the group 3 proteins. The genes encoding the group 2 porin proteins were identified in the late 1980s and consist of two genes, omp2a and omp2b, which are closely linked in the Brucella genome, and which share a great degree of identity (>85%). In the 1990s, two genes were identified coding for the group 3 proteins and were named omp25 and omp31. The predicted amino acid sequences of omp25 and omp31 share 34% identity. The recent release of the genome sequence of B. melitensis 16 M has revealed the presence of five additional gene products homologous to Omp25 and Omp31. The use of recombinant protein technology and monoclonal antibodies (MAbs) has shown that the major OMPs appear to be of little relevance as antigens in smooth (S) B. abortus or B. melitensis infections i.e. low or no protective activity in the mouse model of infection and low or no immunogenicity during host infection. However, group 3 proteins, in particular Omp31, appear as immunodominant antigen in the course of rough (R) B. ovis infection in rams and as important protective antigen in the B. ovis mouse model of infection. The major OMP genes display diversity and specific markers have been identified for Brucella species, biovars, and strains, including the recent marine mammal Brucella isolates for which new species names have been proposed. Recently, Omp25 has been shown to be involved in virulence of B. melitensis, B. abortus and B. ovis. Mutants lacking Omp25 are indeed attenuated in animal models of infection, and moreover provide levels of protection similar or better than currently used attenuated vaccine strain B. melitensis Rev.1. Therefore, these mutant strains appear interesting vaccine candidates for the future. The other group 3 proteins identified in the genome merit also further investigation related to the development of new vaccines.  相似文献   
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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.  相似文献   
8.
Testosterone concentrations in stallions showed a seasonal trend with peak concentrations in the spring (April and May in Britain) and lowest concentrations in the period from December to February. The effect on this pattern of changing the length of the photoperiod at the end of the normal breeding season (mid-summer's day) was studied in 2 experiments. In the first experiment artificial illumination was organised from 21 June to mimic the effect of transfer to a southern hemisphere spring and summer, that is short days becoming longer. The stallions had low concentrations of testosterone in February and high concentrations in April. Concentrations in July, August and September were extremely low with a return to high values in late November/early December. In the second experiment, illumination was maintained at the equivalent of a 16 1/2-hour day from 21 June to mid December. These stallions had high testosterone concentrations in April, after which they fell until August, later rising to a maximum in October. These results are discussed in relation to transfer of stallions between the northern and southern hemispheres.  相似文献   
9.
The Cloward technique for intervertebral fusion was utilized on 12 horses ranging from 3 months to 2 years of age. Of the 12 horses, 9 had been diagnosed as having equine cervical vertebral malformation (CVM) or "wobbles," and 3 were normal controls. A large hole was drilled from the ventral border of the vertebral bodies spanning the intervertebral disc and the vertebral end plates of the 2 articulating vertebrae. Frozen homologous bone dowels of slightly larger diameter from equine cadaver ilia were inserted in the holes. No adverse postoperative complication arose. Clinical improvement was seen in all horses with CVM. Three months postoperatively, partial or complete fusion was evident radiographically in 11 of the 12 horses. Necropsies were performed 3–6 months postoperatively to evaluate the quality of the fusion. Cadaver manipulation demonstrated reduced intervertebral movement at the operative site in all cases. The articulations of the equine cervical spine can be operatively fused by the Cloward technique, and surgically induced trauma is minimal. This technique can be used for stabilizing subluxations and may be applicable for treating fractures and osteolytic processes that have weakened vertebrae.  相似文献   
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