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1.
JF Pycock S. Dieleman P. Drifjhout Y. van der Brug C. Oei GC van der Weijden 《Reproduction in domestic animals》1995,30(4):224-227
2.
Summary Five live virus vaccines against avian infectious laryngotracheitis were studied with regard to safety, immunogenicity and route of administration. Significant differences in virulence between the vaccine strains were found. Reduced virulence was accompanied by a reduction of immunogenicity and capacity to spread. After eyedrop application, a low virulent vaccine induced 90‐ 100% flock immunity for the first 10 weeks after vaccination (PV), followed by a slow decline to 50% at 31 weeks PV, whereas flock immunity induced with the more virulent types remained at about 90% till the end of the experiments (24 and 48 weeks PV). Aerosol vaccination induced 70 ‐ 100% flock immunity but vaccine reactions were severe. Application of vaccine in a coarse spray did not result in adverse vaccine reactions but induced a maximal protection rate of only 50%. Microneutralisation titres provided a useful indicator of immunity from the onset of immunity until immunity started to decline. A vaccine virus carrier state was demonstrated by means of sentinel birds. 相似文献
3.
Summary Four live virus vaccines against Infectious Bursal Disease (IBD) were studied with regard to their safety, immune response and applicability. None of the vaccines caused clinical symptoms or had an adverse impact on bodyweight. Differences between these vaccins were observed in their effect on the Bursa/ Bodyweight Ratio and the severity of the microscopical lesions of the bursa Fabricii. The immunosuppressive effect of IBD vaccination at one day of age on the response to Newcastle disease vaccine applied was rather low. Three of the four vaccines induced antibodies associated with protection against challenge. Vaccination of SPF rearing chickens by drinking water at an age of 15 weeks produced an antibody response (Agar Gel Precipitin Test) whereas at an age of 23, 32 and 60 weeks it did not. Chickens of all age groups responded serologically to an intramusculair vaccination. A correlation was found between the immunological response and the effect of the vaccines on the bursa Fabricii. 相似文献
4.
P.A. Maas M.P.M. de Winter S. Venema H.L. Oei I.J.T M. Claassen 《The Veterinary quarterly》2013,33(4):223-227
Abstract Routine batch control of licensed inactivated viral vaccines for poultry usually includes a potency assay as a measure of vaccine efficacy. Potency assays often consist of vaccination‐challenge experiments in the target species or in laboratory animals. Instead of measuring the protection of vaccinated animals against virulent pathogens, the serological response after vaccination can be quantified for some vaccines. In vitro antigen quantification assays would be attractive alternatives for the current potency assays because the time and costs involved could be greatly reduced and animal use could be avoided. Such in vitro assays will only be acceptable when the correlation between results and efficacy or potency has been demonstrated convincingly. The results of our studies on antigen quantification assays indicate that, in principle, quantification of viral antigens from inactivated oil‐adjuvanted vaccines is feasible and reproducible using specially developed antigen capture ELISAs in combination with specific software for statistical analysis of the ELISA data. We have developed methods to quantify the haemagglutination‐neuraminidase (HN) and fusion (F) proteins of Newcastle disease virus (NDV), the viral protein 3 (VP3) of the infectious bursal disease virus (IBDV), and the spike‐1 (S1) protein of the infectious bronchitis virus (IBV). Vaccination experiments with inactivated ND vaccines indicate that the in vitro quantified HN‐ or F‐proteins of NDV are reliable indicators of the serological response after vaccination. 相似文献
5.
MB Koivisto F Eschricht C Urhausen HO Hoppen M Beyerbach CHY Oei AR Günzel-Apel 《Reproduction in domestic animals》2009,44(S2):320-325
Effects of a short-term hyper- and hypoprolactinaemia on serum concentrations of LH, testosterone and semen quality in six male Beagles were investigated. Blood samples were collected at 3-day intervals for 12 weeks. The time span was divided into five 3-week periods: pre-treatment, metoclopramide (MCP) treatment (0.2 mg/kg orally three times daily), cabergoline (CAB) treatment (5 μg/kg orally once daily), post-treatment 1 and post-treatment 2. In the latter, only semen characteristics were evaluated. Semen parameters were analyzed once per week during the whole 15-week investigation time. At the end of each period, the effects of a single intravenous injection of thyrotropin-releasing hormone (TRH; 10 μg/kg) on the secretion of prolactin (PRL), LH, testosterone, thyroid-stimulating hormone and thyroxine (T4) were investigated. Pre-treatment serum PRL concentration increased under MCP (p < 0.05), followed by a decrease under CAB administration (p < 0.05). Luteinizing hormone and testosterone concentrations were not affected. Except for straight-line sperm velocity, semen quality did not differ between collection periods. A single iv TRH injection induced a significant PRL increase at 20 min in all experimental periods except during CAB treatment. Luteinizing hormone and testosterone did not show clear TRH-related changes. Basic T4 levels were significantly reduced after CAB treatment (p < 0.05). The results of the present study demonstrate that MCP-induced short-term hyperprolactinaemia in male beagles does not seriously affect the hypothalamo-pituitary axis and semen quality. 相似文献
6.
Annemarie Spruijt Hans Kooistra Christine Oei Claudia Vinke Auke Schaefers-Okkens Jeffrey De Gier 《Reproduction in domestic animals》2023,58(1):97-108
Chemical castration, that is the reduction of circulating testosterone concentrations to castrate levels by administration of a GnRH-agonist implant, is a popular alternative to surgical castration in male dogs. Detailed information concerning the pituitary-testicular axis following administration of a GnRH-agonist implant is still scarce. Therefore, GnRH-stimulation tests were performed in male dogs, prior to and after surgical and chemical castration. This approach also allowed us to determine plasma concentrations of testosterone and oestradiol in intact male dogs for future reference and to directly compare the effects of surgical and chemical castration on the pituitary-testicular axis. In intact male dogs (n = 42) of different breeds GnRH administration induced increased plasma LH, FSH, oestradiol and testosterone concentrations. After surgical castration basal and GnRH-induced plasma FSH and LH concentrations increased pronouncedly. Additionally, basal and GnRH-induced plasma oestradiol and testosterone concentrations decreased after surgical castration. After chemical castration, with a slow-release implant containing the GnRH-agonist deslorelin, plasma LH and FSH concentrations were lower than prior to castration and lower compared with the same interval after surgical castration. Consequently, plasma oestradiol and testosterone concentrations were lowered to values similar to those after surgical castration. GnRH administration to the chemically castrated male dogs induced a significant increase in the plasma concentrations of LH, but not of FSH. In conclusion, after administration of the deslorelin implant, the plasma concentrations of oestradiol and testosterone did not differ significantly from the surgically castrated animals. After GnRH-stimulation, none of the dogs went to pre-treatment testosterone levels. However, at the moment of assessment at 4,4 months (mean 133 days ± SEM 4 days), the pituitary gonadotrophs were responsive to GnRH in implanted dogs. The increase of LH, but not of FSH, following GnRH administration indicates a differential regulation of the release of these gonadotrophins, which needs to be considered when GnRH-stimulation tests are performed in implanted dogs. 相似文献
7.
Five live virus vaccines against avian infectious laryngotracheitis were studied with regard to safety, immunogenicity and route of administration. Significant differences in virulence between the vaccine strains were found. Reduced virulence was accompanied by a reduction of immunogenicity and capacity to spread. After eyedrop application, a low virulent vaccine induced 90-100% flock immunity for the first 10 weeks after vaccination (PV), followed by a slow decline to 50% at 31 weeks PV, whereas flock immunity induced with the more virulent types remained at about 90% till the end of the experiments (24 and 48 weeks PV). Aerosol vaccination induced 70-100% flock immunity but vaccine reactions were severe. Application of vaccine in a coarse spray did not result in adverse vaccine reactions but induced a maximal protection rate of only 50%. Microneutralisation titres provided a useful indicator of immunity from the onset of immunity until immunity started to decline. A vaccine virus carrier state was demonstrated by means of sentinel birds. 相似文献
8.
Summary Four live virus vaccines against Infectious Bursal Disease (IBD) were studied with regard to their safety, immune response and applicability. None of the vaccines caused clinical symptoms or had an adverse impact on bodyweight. Differences between these vaccins were observed in their effect on the Bursa/ Bodyweight Ratio and the severity of the microscopical lesions of the bursa Fabricii. The immunosuppressive effect of IBD vaccination at one day of age on the response to Newcastle disease vaccine applied was rather low. Three of the four vaccines induced antibodies associated with protection against challenge. Vaccination of SPF rearing chickens by drinking water at an age of 15 weeks produced an antibody response (Agar Gel Precipitin Test) whereas at an age of 23, 32 and 60 weeks it did not. Chickens of all age groups responded serologically to an intramusculair vaccination. A correlation was found between the immunological response and the effect of the vaccines on the bursa Fabricii. 相似文献
9.
Knowledge of the dose-response relation of inactivated vaccines and of the factors that influence this relation is essential for the evaluation of existing vaccine potency assays and the development of new potency assays that are based on the antigen content of the inactivated vaccines. We quantified the relation between vaccine dose, serologic response, and clinical protection after vaccination for three different inactivated Newcastle disease (ND) vaccines. Qualitatively, similar dose-response curves were obtained for the three vaccines when either the serologic response or the clinical protection of specific-pathogen-free (SPF) chickens was plotted against the different vaccine doses applied. However, the vaccines differed quantitatively: doses of vaccines that induced similar antibody titers or clinical protection differed 2-8-fold. In contrast with the narrow range of antibody titers induced by a full vaccine dose, a very broad range of titers was obtained after dilution of the vaccines. At least 95% of the SPF chickens with detectable antibody in the serum were protected against a challenge with virulent Herts ND virus. The relation between the dosage of two different ND vaccines and the serum antibody titers remained markedly constant between 3 and 18 wk after vaccination. Vaccination of broilers instead of layers with a dilution series of inactivated ND vaccine resulted in significantly lower antibody levels and less clinical protection against virulent challenge. In conclusion, despite quantitative differences, we found comparable dose-response relations for the three inactivated ND vaccines studied. 相似文献
10.
Routine batch control of licensed inactivated viral vaccines for poultry usually includes a potency assay as a measure of vaccine efficacy. Potency assays often consist of vaccination-challenge experiments in the target species or in laboratory animals. Instead of measuring the protection of vaccinated animals against virulent pathogens, the serological response after vaccination can be quantified for some vaccines. In vitro antigen quantification assays would be attractive alternatives for the current potency assays because the time and costs involved could be greatly reduced and animal use could be avoided. Such in vitro assays will only be acceptable when the correlation between results and efficacy or potency has been demonstrated convincingly. The results of our studies on antigen quantification assays indicate that, in principle, quantification of viral antigens from inactivated oil-adjuvanted vaccines is feasible and reproducible using specially developed antigen capture ELISAs in combination with specific software for statistical analysis of the ELISA data. We have developed methods to quantify the haemagglutination-neuraminidase (HN) and fusion (F) proteins of Newcastle disease virus (NDV), the viral protein 3 (VP3) of the infectious bursal disease virus (IBDV), and the spike-1 (S1) protein of the infectious bronchitis virus (IBV). Vaccination experiments with inactivated ND vaccines indicate that the in vitro quantified HN- or F-proteins of NDV are reliable indicators of the serological response after vaccination. 相似文献