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991.
Three separate experiments were conducted to determine if the addition of carbohydrate sources directly to freshly-produced laying hen manure reduced the loss of gaseous nitrogen containing compounds during 7 d of storage. The addition of sucrose (8 g/kg) to the manure resulted in a greater increase in bacterial numbers, a greater loss of carbon and a trend for a reduced loss of nitrogen. Although glucose addition to the manure increased bacterial numbers and tended to increase carbon loss, nitrogen loss increased relative to the control. Addition of straw to the manure did not affect the change in bacterial numbers or rate of nitrogen loss compared to the control treatment. Experiment 2 indicated that, when either sucrose or maltose were mixed (8 g/kg) with laying hen manure, microbial numbers were increased and gaseous nitrogen losses were reduced. A combination of starch plus alpha-amylase did not affect the characteristics of the manure. Experiment 3 showed that increasing sucrose addition gave a non-linear reduction in nitrogen loss. Minimum nitrogen loss was obtained with 35 g/kg sucrose, though the maximum increase in bacterial numbers occurred at 20 g/kg of added sucrose.  相似文献   
992.
A 3-year-old dog with cervical myelopathy resulting from a vascular anomaly is described. Marked intradural-extramedullary spinal cord compression was observed, in association with multilevel ectatic anastomotic radicular arterial branches connecting the left and right vertebral arteries. A nonpatent proximal segment of the right subclavian artery had resulted in compensatory enlargement of the left vertebral artery. Flow within the right vertebral artery was retrograde and fed into the patent distal segment of the right subclavian artery. Multiple imaging techniques including myelography, computed tomography, magnetic resonance imaging, and selective digital angiography were used to document this anomaly. To reduce spinal cord compression the largest collateral vessel was embolized without complication. Good clinical response was observed within 6 weeks and improved clinical neurologic function was maintained at the time of a 12-month re-evaluation.  相似文献   
993.
CASE DESCRIPTION-A 4-year-old Quarter Horse stallion was evaluated because of a 10-month history of moderate (grade 3/5) left forelimb lameness (detectable during trotting over a smooth, hard surface). CLINICAL FINDINGS-No abnormalities were detected in either forelimb via palpation or application of hoof testers; however, lameness was eliminated after administration of a palmar digital nerve block in the left forelimb. Whereas radiography and ultrasonography did not identify any left forelimb foot abnormalities, magnetic resonance (MR) imaging revealed a circumscribed soft tissue mass in the distal aspect of the digital flexor tendon sheath (DFTS) dorsal to the lateral aspect of the deep digital flexor tendon. Subsequently, the left forelimb DFTS was injected with local anesthetic, which resulted in 90% improvement of the horse's lameness. TREATMENT AND OUTCOME-The distal aspect of the left forelimb DFTS was evaluated tenoscopically. The mass was removed under tenoscopic guidance, after which the distal digital annular ligament was transected. The horse received phenylbutazone orally for 10 days, and the left forelimb DFTS was injected with hyaluronic acid and methylprednisolone acetate 7 days after the surgery. Following a rehabilitation program, the horse was returned to full training at 6 months after surgery and competed successfully during a 2-year follow-up period. CLINICAL RELEVANCE-Use of MR imaging should be considered in all lame horses for which a definitive diagnosis cannot be made via radiography, ultrasonography, or other imaging techniques, especially when the lameness has been localized to a specific anatomic region by use of diagnostic anesthesia.  相似文献   
994.
A species specific PCR test, based on manganese-dependent superoxide dismutase A encoding gene sodA, was developed for the identification of Staphylococcus hyicus, an important bacterial pathogen in pigs. The designed primers allowed a rapid and reliable identification of phenotypically characterized S. hyicus, isolated in Russia, Germany and Denmark. No cross reactivities could be observed investigating staphylococcal reference strains representing 18 different species and subspecies. The use of the described primers might improve a future diagnosis of this bacterial pathogen.  相似文献   
995.
996.
Several European countries have initiated national and regional control-and-eradication campaigns for bovine viral diarrhea virus (BVDV). Most of these campaigns do not involve the use of vaccines; in Germany, vaccination is used only in states in which it is considered necessary because of high BVDV prevalence. In European countries without organized BVDV control programs, vaccination is commonly used to control BVDV. Diagnostic test strategies are fundamental to all control-and-eradication campaigns; therefore, the purpose of this review is to describe how the available diagnostic tests are combined into test strategies in the various phases of control-and-eradication campaigns in Europe. Laboratory techniques are available for BVDV diagnosis at the individual animal level and at the herd level. These are strategically used to achieve 3 main objectives: 1) initial tests to classify herd status, 2) follow-up tests to identify individual BVDV-infected animals in infected herds, and 3) continued monitoring to confirm BVDV-free status. For each objective or phase, the validity of the diagnostic tests depends on the mode of BVDV introduction and duration of infection in test-positive herds, and on how long noninfected herds have been clear of BVDV. Therefore, the various herd-level diagnostic tools--such as antibody detection in bulk milk or in blood samples from young stock animals, or BVDV detection in bulk milk--need to be combined appropriately to obtain effective strategies at low cost. If the individual diagnostic tests are used with due consideration of the objectives of a specific phase of a BVDV control program, they are effective tools for controlling and eradicating BVDV in regions not using vaccination and where vaccination is a part of the control or eradication program.  相似文献   
997.
OBJECTIVE: To evaluate effects of 2 commercially available colostrum replacement products on serum IgG and total protein concentrations in dairy calves. DESIGN: Prospective clinical trial. ANIMALS: 84 Holstein bull calves from a single dairy. PROCEDURES: Calves were randomly assigned to be given 4 quarts of colostrum (group 1; n = 21), 2 packages of a colostrum replacement product (product A; group 2; 21), 1 package of a different colostrum replacement product (product B; group 3; 21), or 2 packages of product B (group 4; 21). Treatments were given within 3 hours after birth, and blood samples were collected 24 hours later and submitted for determination of serum total protein and IgG concentrations. RESULTS: Group 1 calves had significantly higher serum total protein and IgG concentrations than did calves in the other 3 groups. However, the percentage of calves with adequate passive transfer (ie, serum IgG concentration > 1,000 mg/dL) was not significantly different among groups 1 (90%), 3 (81%), and 4 (95%). In contrast, only 10% of calves in group 2 had adequate passive transfer. It was predicted that calves fed product B that had serum total protein concentrations > 5.2 g/dL would have serum IgG concentrations > 1,000 mg/dL at least 90% of the time. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that product B could be considered as an alternative to colostrum in dairy calves, but product A failed to routinely provide adequate serum IgG concentrations when fed according to label directions.  相似文献   
998.
999.
A three year long experimental study was carried out to investigate horizontal MVV-infection by PCR and ELISA, in 191 one year-old latxa dairy-sheep raised in two separate groups under low and high MVV-infection pressure, respectively. Sheep originated from a previous MVV-transmission study in lambs and seroprevalence among one year-old sheep in both groups was 15% approximately. The high infection-pressure group (H-group) consisted of 147 replacement ewes that joined a milk-producing, housed dairy-flock with 42-66% MVV-seroprevalence and the low infection-pressure group (L-group) were castrated males raised in a separate shed. In contrast to results obtained when infection was investigated in lambs, the overall degree of agreement between ELISA and PCR results was very good and there was some indication that it increased further as sheep became older. MVV-prevalence did not change in the L-group and increased to 57% in three year-old sheep in the H-group (p<0.001). Random effects logistic regression confirmed seroconversion was significantly higher in the H-group compared to the L-group and was highest during the year after the sheep were introduced in the dairy flock and did not increase with age as in previous studies using less sensitive antibody assays. The evidence that horizontal transmission can be very low in spite of prolonged close contact between infected and non-infected sheep is valuable for MVV-control purposes. Furthermore it highlights the need to investigate virus excretion dynamics in infected animals and animal to animal transmission to improve our overall understanding of horizontal MVV transmission in MVV endemic populations.  相似文献   
1000.
A reverse line blot hybridization (RLB) one-stage nested PCR (nPCR) for Anaplasma centrale and a nested PCR for Anaplasma marginale were used to detect infected cattle grazing within an endemic region in Israel. A novel set of PCR primers and oligonucleotide probes based on a 16S ribosomal RNA gene was designed for RLB detection of both Anaplasma species, and the performance of the molecular assays compared. The immunofluorescent antibody test (IFA) was used to detect antibodies to both Anaplasma species, whereas, a highly sensitive and specific competitive enzyme-linked immunosorbent assay (cELISA) was used to detect antibodies in A. centrale-vaccinated cattle. The RLB and the nested PCR procedures showed bacteremia with sensitivity of 50 infected erythrocytes per milliliter. Up to 93% of the A. centrale vaccinates carried specific antibodies that were detected by cELISA, and up to 71% of the vaccinated cattle were found to be naturally infected with A. marginale according to the PCR and the RLB assays. Nevertheless, no severe outbreaks of A. marginale infection occurred among vaccinated herds in this endemic region. It appears that both, molecular tools and serology are useful for evaluation of the vaccine efficacy. In the light of wide natural field infection with A. marginale, strong recommendations to continue the A. centrale vaccination program regime will continue until a new generation of non-blood-based vaccine will be developed.  相似文献   
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