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51.
Temporal ELISA response of rams to Brucella ovis following experimental infection or vaccination 总被引:1,自引:0,他引:1
Sera from rams vaccinated with antigens extracted chaotropically from Brucella ovis by potassium thiocyanate treatment were used to optimise a whole-cell, enzyme-linked immunosorbent assay (CELISA) and to monitor the temporal serological response of rams which had been challenged with infected semen by the intranasal or intrapreputial route. Three patterns of CELISA response were detected. Thirteen of 15 rams intranasally challenged did not respond serologically (pattern 1 or nil response). Only one of 15 rams in the intranasal group exhibited a rise and fall response with CELISA (pattern 2), while another showed a rise and surge response (pattern 3). The numbers of rams in the intrapreputial group which displayed a pattern 1 or 2 or 3 response were four, nine and two, respectively. No ram with a pattern 2 response excreted B ovis in the semen or showed any other evidence of infection, whereas rams with a pattern 3 response excreted B ovis in the semen and developed palpable lesions. Intrapreputially challenged rams that were CELISA-positive consistently mounted an antibody response against B ovis about two to four weeks earlier than intranasally challenged rams. 相似文献
52.
在查清天津市园林主要花灌木刺吸口器害虫桃粉蚜、绣线菊蚜、棉蚜和山楂红蜘蛛发生消长规律的基础上 ,确定了防治适期和结合点 ,筛选出 10 %吡虫啉、绿灵、蚧螨灵、 1. 8%齐螨素和花保5种低、无毒药剂 ,防效均达到 90 %以上。查出天敌 13种 ,并对优势种作了取食量调查 相似文献
53.
根据饲料可消化氨基酸研制肉仔鸡无鱼粉饲粮试验 总被引:1,自引:0,他引:1
选用240只AA商品代出壳肉仔鸡进行试验,以探讨根据饲料中可消化氨基酸含量,研制菜籽粕型无鱼粉低蛋白肉仔鸡饲粮的饲用效果。结果表明:以可消化氨基酸为基础研制的菜籽粕型无鱼粉肉仔鸡低蛋白平衡饲粮,可降低饲粮蛋白质水平1-1.5个百分点,试验鸡49日龄体重达2158.26克、料肉比2.15:1,增重和饲料转化率均达到或接近鱼粉型高蛋白饲粮的效果;每吨菜籽粕型无鱼粉饲粮可比鱼粉型饲粮降低原料成本72-8 相似文献
54.
对5个无核葡萄品种的试验表明,不同培养方式对离体胚发育的影响是很明显的,其中4个品种胚发育率液体培养高于固体培养,‘京早晶’在液体培养中胚发育率高达73.7%,是目前国内外胚发育率最高的报道;液体培养比固体培养胚的发育程度高,发育整齐,无畸形胚,易成苗. 相似文献
55.
The crossreactivity of mouse monoclonal antibodies (MoAbs) (Tab. I) prepared against human HLA-DR and HLA-DP antigens was studied in various bovine cells: lymphocytes from lymph nodes and peripheral blood, adherent (B) and nonadherent (T) lymphocytes, monocytes, granulocytes and platelets. In the immunofluorescence test, MoAbs Bra13, Bra14, Bra20, Bra22, Bra30, Bra70, HL-38 reacted with bovine B lymphocytes and monocytes, but not with other tested cells (Tab. III, IV). These antibodies, except Bra22, were positive with B lymphocytes in the complement dependent cytotoxic test (Tab. II). The similarity of the bovine antigens and HLA-DR antigens determined by used MoAbs was also proved by immunoblotting. Monoclonal antibodies Bra38 and BraFB6 did not react with the bovine cells and separated antigens. The epitope (HLA-DR) recognized by the antibody Bra38 is probably absent in cattle. The presence of HLA-DP analogue determined by the antibody BraFB6 has not been confirmed. The crossreactive MoAbs could be used for the detection of B lymphocytes and macrophages in veterinary immunology. 相似文献
56.
J A Ellis H Russell J Cavender T R Haven 《Veterinary immunology and immunopathology》1992,34(1-2):35-45
Cattle were immunized with vaccines containing modified-live or inactivated bovine respiratory syncytial virus (BRSV) and serum antibody responses were analyzed. Compared with preinculation values, at Day 14 after two biweekly immunizations with modified-live or inactivated vaccines there were significant increases in BRSV-specific titers in the sera of cattle that received both types of vaccines, as determined by a whole cell ELISA. Using a blocking ELISA and radioimmune precipitation it was determined that there was recognition of the fusion (F) protein by antibodies from cattle that received both types of BRSV antigens: however, virus neutralization assays revealed that only cattle that received modified live virus, either in monovalent or polyvalent vaccines, developed neutralizing antibodies to BRSV after two immunizations. These results indicate that inactivation of BRSV can lead to a dissociation between serological recognition of the F protein and virus neutralization in vaccinated cattle. 相似文献
57.
Administration of progesterone in poly(d-,l-lactide) microspheres was used to maintain pregnancy in mares after luteolysis was induced by treatment with prostaglandin F2 alpha at day 14 of pregnancy. Mares were given vehicle only (control, n = 6) or 0.75 g (n = 7), 1.5 g (n = 8), or 2.25 g (n = 5) of microencapsulated progesterone at days 12 and 22 of pregnancy. Serum progesterone concentrations were determined daily, and pregnancy was evaluated by transrectal ultrasonography on alternate days. Significantly (P less than 0.05) more mares given 1.5 or 2.25 g of progesterone (6 of 8 and 4 of 5 mares, respectively), but not those given 0.75 g (3 of 7 mares), maintained pregnancy through day 32, compared with control mares (0 of 6). Progesterone concentrations decreased significantly (P less than 0.025) in all groups after administration of prostaglandin F2 alpha at day 14, and significant (P less than 0.05) effects of time and treatment on progesterone concentrations were found between days 12 and 22, and 22 and 32. Although treatment with 1.5-g and 2.25-g doses of microencapsulated progesterone improved maintenance of pregnancy, compared with that of vehicle-treated controls, administration of 2.25 g of microencapsulated progesterone appeared to be most efficacious in maintenance of pregnancy during the study interval. 相似文献
58.
Neutrophils were isolated from the blood of pregnant cows on days 255, 265, and 275 of pregnancy, and on the day of parturition (n = 5/group), and in addition, simultaneously from 4 ovariectomized healthy cows (control animals). Neutrophils were subjected to neutrophil function assays (chemotaxis against zymosan-activated serum, random migration, ingestion of 125I-iododeoxyuridine [IdUR]-labeled Staphylococcus aureus, iodination of proteins, cytochrome C reduction, antibody-independent and antibody-dependent cell-mediated cytotoxicity). Results were expressed as percentage of control animals. Fetal placental tissue (cotyledon), uterine wall tissue, and skeletal muscle were obtained from the principal animals on the aforementioned days via laparotomy, and tissue suspensions were prepared. Chemotaxis of neutrophils was tested against tissue supernatants. Compared with day 255, there was an increase in ingestion of 125I-IdUR-S aureus at parturition, whereas iodination of proteins and cytochrome C reduction were reduced on the day of calving. The other neutrophil functions tested did not change over time of gestation. Fetal placental and uterine wall tissue attracted neutrophils with uterine wall tissue having a tendency to be more potent than cotyledonary tissue. Skeletal muscle tissue did not attract neutrophils. There was no change in chemotaxis response of neutrophils evoked by intrauterine and uterine tissues over time of gestation. It was concluded that at parturition, neutrophil function is impaired with respect to their bactericidal effects, which may render the animal more susceptible to bacterial infections, and that the chemoattractant properties of fetal placental and uterine wall tissues are tissue-specific, at least when compared with skeletal muscle.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
59.
C Cervantes J B Madison N Ackerman W O Reed 《Journal of the American Veterinary Medical Association》1992,200(12):1997-2000
Between January 1985 and May 1989, 53 Thoroughbred horses (mean age 3.2 years) were surgically treated for dorsal cortical fractures of the third metacarpal bone (MC III). All horses were treated with cortical drilling through the fracture line (osteostixis). Diagnosis of the fractures was confirmed by xeroradiography. Lifetime racing records were obtained for all horses. Forty-seven horses returned to racing after surgery (89%). The mean time between surgery and the first race was 6.8 months. Horses had a mean of 10.9 starts before surgery and 16.1 starts after surgery. The mean earnings per start before surgery was $6,459 and after surgery was $5,685. Of the 47 horses that raced after surgery, 70% raced at the same class or improved. Complications related to surgery were seen in 10 horses. Two horses had a second fracture of MC III at the same site, and were again treated by osteostixis, after which both horses returned to competition. Fractured drill bits were left in the MC III of 4 horses. One of these horses had catastrophic failure of MC III. Two horses developed subcutaneous infections and 2 horses had catastrophic failure of MC III in the surgically treated limb. Osteostixis appears to be an effective treatment for returning horses affected with dorsal cortical fractures to racing. 相似文献
60.
A previously undocumented hypokalaemic condition with a cyclical nature, comprising acute bouts of polymyopathy followed by spontaneous recoveries, is described in the cat. Cats being fed a high protein vegetarian diet developed recurrent episodes of polymyopathy, characterised by ventroflexion of the head and neck, stiff forelimb gait, lateral head-resting and generalised muscle weakness. Plasma potassium concentrations (mean +/- standard deviation) were reduced from 3.28 +/- 0.33 mmol/l at the beginning of the experiment to 2.45 +/- 0.24 mmol/l during bouts of myopathy. This hypokalaemia was associated with increased creatine kinase activities indicative of muscle damage, and decreased urinary potassium concentrations, and was caused by insufficient dietary potassium. Cats that received the same diet supplemented with potassium did not develop hypokalaemic polymyopathy. Spontaneous recoveries of affected cats were not associated consistently with increases in plasma potassium concentrations. Plasma taurine concentrations decreased and glutamic acid increased markedly in all cats fed the experimental diet. There was no evidence of thiamin deficiency associated with the high glutamic acid intake. Veterinarians should be aware that hypokalaemic cats, and in particular those on potassium-deficient diets, may show cyclical disease with episodes of polymyopathy recurring after periods of spontaneous clinical recovery. This condition in cats may be a useful animal model for familial hypokalaemic periodic paralysis in humans. 相似文献