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1.
Twelve commercial 5-component clostridial vaccines with known variations in potency of the blackleg (Clostridium chauvoei) component, were simultaneously tested in sheep and guinea pigs. Controlled challenge experiments provided evidence of a highly significant correlation in the response of the 2 species. The guinea pig laboratory model is considered to be a valid indicator of field performance for vaccines containing blackleg antigen. 相似文献
2.
Cell culture assays are possible alternatives to replace in vivo neutralization tests currently required for potency testing of clostridial vaccines. Cell culture assays based on the MDCK cell line and the Vero cell line which are sensitive to the Clostridium (C.) perfringens type D epsilon toxin and Clostridium novyi type B alpha toxin, respectively, were developed, and the test conditions were standardized. The antibody titres of vaccinated rabbits measured in vitro were compared with the results of current test procedures recommended by European Pharmacopoeia. The correlation coefficients calculated were significant for all sera tested. The cell culture assays proved to be sensitive, specific, reproducible and reliable. Therefore, these cell culture assays could be suitable in vitro alternatives to the in vivo mouse neutralization experiments required for potency tests of clostridial vaccines, but further validation studies are necessary. 相似文献
3.
Six commercially available clostridial vaccines comprising one oil-emulsion, two alum-precipitated and three aluminum hydroxide adjuvanted preparations, each containing between two and seven antigenic components, were administered to groups of 10 rabbits and eight sheep in accordance with manufacturers' recommendations. Serum antitoxic values to Cl welchii beta, Cl welchii epsilon, Cl septicum, Cl oedematins and Cl tetani toxins were determined 14 days after completion of each vaccination course. The overall pattern of mean antitoxic values was found to be similar in sheep and rabbits, a vaccine eliciting a comparatively high antibody titre to any given antigen component in sheep also inducing a comparatively high titre in the corresponding group of rabbits. Similarly, comparatively poor responses in sheep were associated with poor responses in rabbits. The degree of variation in response within groups of animals was greater in sheep than in rabbits for all five antigenic components assayed. Sheep consistently developed higher titres than rabbits to Cl oedematins component but consistently lower titres to both Cl welchii beta and epsilon components irrespective of the type of vaccine used. The response of both species to Cl tetani antigen was similar in terms of serum antitoxic values. It was concluded that rabbits provide a suitable model for the assessment of potency of sheep clostridial vaccines. 相似文献
4.
Guinea pig protection test as indicator of potency of oil emulsion foot-and-mouth disease vaccines 总被引：1，自引：0，他引：1
A vaccine potency test is described involving virus challenge to six groups of 10 guinea pigs at five weeks after vaccination. Sixteen oil emulsion foot-and-mouth disease vaccines were so tested and nine retested after storage at 4 degrees C for up to 28.3 months. The results were compared with those of the routinely used oil emulsion vaccine potency test (protection afforded to eight pigs challenged 21 days after vaccination). When guinea pig estimates of 3 log2 PD50 or more were obtained, then, with one exception, the batches protected all or almost all pigs from challenge, but when the guinea pig estimates were less than 1 log2 PD50, the vaccines failed to protect five out of eight pigs. The sensitivity and reproducibility of the guinea pig method, established by repeated tests on two vaccine batches, seemed acceptable. The results suggested that guinea pig estimates might provide a suitable substitute for pig challenge potency tests because they reflected the potency of the vaccines, were likely to involve smaller standard errors and caused less discomfort to animals. 相似文献
5.
Efficacy of ten commercial Campylobacter fetus vaccines was tested in pregnant guinea pigs and compared with that of an experimental vaccine prepared from the challenge-exposure strain. If the first lot of vaccine failed to protect 50% of the guinea pigs, one or two additional lots of that vaccine were purchased and retested. Three vaccines for cattle, evaluated, as the most effective of those tested, protected 62%, 72%, and 89% of the guinea pigs from abortion; the experimental vaccine protected 98%. The two vaccines for sheep protected 50% and 61% of the guinea pigs from abortion. With the other five vaccines produced for immunizing cattle, protection was from 0% to 36%, with the exception of one lot of a vaccine that protected 74%. Blood infection was found at necropsy in only 6% of the guinea pigs given vaccines that protected 50% or more from abortion, but was found in 66% of those given vaccines that protected less than 50%. Similarly, tissue infection was found at necropsy in only 18% of the guinea pigs given vaccines that protected more than 50%, but was found in 91% of those given vaccines that protected less than 50% from abortion. Oil-emulsion adjuvants appeared to enhance protection from abortion and infection. Nodules persisted at the injection site in most of the guinea pigs immunized with vaccines containing oil-emulsion adjuvants, but rarely persisted in guinea pigs given aqueous-phase adjuvant vaccines. Comparison of efficacy of the vaccines in guinea pigs with efficacy in sheep and cattle remains to be made. 相似文献
6.
7.
Concentrated cell culture fluids of African horse sickness virus were shown to agglutinate erythrocytes from cattle, horses, sheep, goats, guinea pigs, rabbits, and poultry at 4°C, room temperature, and 37°C. The titres obtained were dependent on pH and NaCl molarity of the diluent, optimal titres being obtained at pH 7.5 and 0.6 M NaCl. The HA inhibiting antibodies to two AHS viruses were proven to be type specific. 相似文献
8.
Antibody responses of guinea-pigs, rabbits and pigs to inactivated porcine parvovirus vaccines 总被引：3，自引：0，他引：3
Antibody responses were compared in guinea-pigs, rabbits and pigs following vaccination with inactivated porcine parvovirus (PPV) vaccines. Mean PPV hemagglutination inhibition (HI) antibody titers of 52, 56 and 36 at 1 week after first vaccination and 896, 640 and 512 at 2 weeks after second vaccination were detected in guinea-pigs, rabbits and pigs, respectively. PPV vaccines prepared with greater concentrations of virus, as determined by hemagglutination (HA) units, and of aluminum hydroxide gel adjuvant, induced higher HI antibody titers in guinea-pigs. Optimal concentrations for inducing consistently high antibody titers consisted of vaccine virus with a HA titer of 256/0.1 ml and gel adjuvant at a final concentration of 50%. A second vaccination at 4 weeks compared to 2 or 3 weeks after first vaccination resulted in higher mean HI titers. These data provide preliminary information on the use of guinea-pigs or rabbits as laboratory animal models for testing the potency of PPV vaccines. 相似文献
9.
Sheep were immunised with Corynebacterium pseudotuberculosis toxoid formulated as a monocomponent vaccine with aluminium adjuvant or in combination with 5 clostridial antigens, and also in the combined form with sodium selenate. Immunised and control sheep were experimentally infected 16 days after vaccination and slaughtered and inspected after a further 3 months to determine their resistance to infection. All 3 vaccines afforded an equal and high level of protection; 91% of vaccinated sheep exhibiting no lesions of caseous lymphadenitis compared with 51.5% affected sheep in the control group. Average lesion counts were 1.2 per affected vaccinated sheep and 4.5 per affected control sheep. Antitoxin responses to the clostridial toxoids incorporated in the combined vaccines were not affected by inclusion of the C pseudotuberculosis toxoid or the sodium selenate. 相似文献
10.
A total of 288 serum samples were collected from 12 species of animals in various localities of Japan from 1975 to 1977. Neutralizing antibody to bovine rotavirus was found in serum samples from all the species, viz., horses, cattle, sheep, goats, pigs, dogs, rabbits, guinea pigs, rats, mice, chickens and human beings. The incidence of neutralizing antibody in titers of 1 : 2 or higher ranged from 31 to 100%, and high incidences exceeding 70% were obtained in horses, cattle, sheep, pigs, dogs, rabbits and human beings. High titers were most common in horses, cattle, sheep and pigs. These serological results suggest that rotaviruses occur commonly in these species of animals. 相似文献
11.
《Preventive veterinary medicine》1988,6(3):235-238
Cichorium pumilum Jacq. is an annual plant, widely distributed in the Middle East. When it flowers during April, May and June it is claimed by sheep farmers, to be poisonous to sheep, producing symptoms similar to those of babesiosis. The results of 4 years of clinical studies on sheep reported to be ill owing to C. pumilum toxicity, revealed that they were actually suffering from babesiosis. Experimental groups of sheep, rabbits and guinea pigs were fed on freshly-collected flowering C. pumilum for a minimum of 10 days showed no symptoms of ill health. A small flock of sheep survived grazing naturally on C. pumilum for the months of April, May and June. 相似文献
12.
Amimoto K Oishi E Yasuhar H Sasak O Katayama S Kitajima T Izumida A Hirahara T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(8):879-883
The protective effects of Clostridium sordellii lethal toxin (LT) and hemorrhagic toxin (HT) toxoids against challenge with spores in guinea pigs were investigated. Purified LT and partially purified HT were obtained from the culture supernatant of C. sordellii strain 3703, and then were treated with formalin to make toxoids. LT. HT and combined LT and HT (LT/HT) toxoid vaccines were prepared by mixing each toxoid with an aluminum phosphate gel as adjuvant. Guinea pigs immunized twice with the respective toxoid vaccines were challenged with spores of strains 3703 or KZ1047. The latter strain does not produce HT. LT toxoid vaccine conferred protection against challenge with strain KZ1047, but not strain 3703, in guinea pigs. All guinea pigs immunized with HT toxoid vaccine died after challenge with spores of either strain. LT/HT toxoid vaccine gave complete protection against challenge with spores of strains 3703 and KZ1047 to guinea pigs. These results suggest that not only LT toxoid, but also HT toxoid, are essential protective antigens of C. sordellii. 相似文献
13.
Groups of sheep were dosed with vaccines containing Corynebacterium pseudotuberculosis toxoid combined in varying amounts with 5 clostridial antigens. Resistance of the sheep to infection with C pseudotuberculosis was tested at 1, 6 and 12 months after vaccination by infection with pus from ovine lymph glands actively infected with C pseudotuberculosis. The outcome was assessed 3 months after challenge by slaughter and inspection of the sheep for caseous lymphadenitis lesions. Protection was demonstrated by a significant reduction in the proportion of immunised sheep exhibiting lesions compared with control sheep, and by fewer abscesses in affected immunised sheep than in affected control sheep. A positive correlation was found between amount of C pseudotuberculosis toxoid administered and degree of protection obtained. Chromatographically-purified toxoid induced essentially the same protection, suggesting that anti-toxic immunity is the major factor in protection. 相似文献
14.
Immunisation against ovine caseous lymphadenitis: comparison of Corynebacterium pseudotuberculosis vaccines with and without bacterial cells 总被引：2，自引：0，他引：2
Sheep were immunised with Corynebacterium pseudotuberculosis vaccines prepared from cell-free toxoid or from toxoid with formalin-killed cells of C pseudotuberculosis added. Resistance of sheep to infection was tested 6 months after immunisation by inoculation with caseous lymphadenitis pus. The outcome was assessed 3 months later by slaughter and inspection of the sheep for lesions of caseous lymphadenitis. immunised sheep were adequately protected against infection as shown by a significant reduction in the number of sheep exhibiting lesions compared with control sheep, and by fewer abscesses in affected vaccinated sheep than in affected control sheep. The protective potency of the vaccines was not improved by the inclusion of cells of C pseudotuberculosis. 相似文献
15.
Goats, guinea pigs and rabbits were immunized with bovine IgM or with intact molecules, heavy chains, Fc portions or light chains of bovine IgG1 and IgG2. Rabbits and guinea pigs were immunized with bovine secretory IgA. Goats and guinea pigs produced heavy chain specific antisera to intact IgM whereas rabbits produced anti-light chain antibody and in one instance anti-alpha 2-macroglobulin antibody in addition to the anti-mu response. Goats and guinea pigs produced antisera to bovine IgG1 and IgG2 and their Fc portions that needed little absorption to render them monospecific for the heavy chain. In addition to antibody to the heavy chains, rabbits produced anti-light chain antibody when immunized with intact IgG1 or IgG2 molecules. These latter sera, and those produced by rabbits immunized with Fc portions of IgG1 or IgG2 required extensive absorption before they were monospecific for their respective heavy chains. Heavy chains were poor immunogens in all three species. Rabbits immunized with IgA produced both anti-alpha and anti-light chain antibodies while guinea pigs produced sera with antibody activity to the alpha chain only. 相似文献
16.
Joyappa DH Sasi S Ashok KC Reddy GR Suryanarayana VV 《Veterinary research communications》2009,33(3):263-271
RNA interference (RNAi) has been used as an effective antiviral strategy for its specific silencing of viral gene expression in mammalian cells. In this study, shRNA targeting two regions of Foot and Mouth Disease Virus (FMDV) i.e. 3D and 5'UTR which are very essential in virus replication were evaluated. The constructs were made using h7K RNA polymerase III promoter. We investigated in vivo inhibitory effect of shRNA on FMDV replication in BHK-21 cells and guinea pigs. The results showed that transfection of 3D shRNA could reduce virus growth by three folds when cells were challenged with 10(2) TCID(50) of FMDV. Pretreated guinea pigs with 3DshRNA were protected 80% with 10(3) GPID(50) of FMDV. As a first report in guinea pigs which are recognized animal model for FMD vaccine potency testing, the study suggests that shRNA could be a viable therapeutic approach to control severity of FMD infection and spread. 相似文献
17.
When 400 micrograms ivermectin/kg was administered subcutaneously to rabbits infected with the ear mite Psoroptes cuniculi it significantly reduced the clinical score, and when 500 micrograms ivermectin/kg was administered subcutaneously to guinea pigs with mange due to Trixacaurus caviae it resulted in a clinical cure. In rabbits a subcutaneous dose of 400 micrograms/kg produced high and sustained concentrations of ivermectin in the tissues and body fluids for at least 13 days and its rate of depletion from tissues was similar to that observed in sheep and rats. The mean (+/- sem) maximum concentration in plasma was 42.0 +/- 9.7 ng/ml 37.2 +/- 5.0 hours after administration and the area under the concentration-time curve was 3543 +/- 580 ng/ml hours. After the administration of 500 micrograms ivermectin/kg to guinea pigs orally, subcutaneously or topically the drug could be detected in the plasma only after subcutaneous administration. The mean concentration 72 hours after its administration to four guinea pigs was 0.7 +/- 0.3 ng/ml. 相似文献
18.
Luick K Gottschaldt J Schulze F Werner E Erler W Borrmann E 《DTW. Deutsche tier?rztliche Wochenschrift》2002,109(4):178-182
The toxin binding inhibition test (ToBI) were developed for potency testing of C. novyi type B alpha toxoid containing veterinary vaccines to replace the currently used toxin neutralisation test in mice (TNT). The antitoxin titres of rabbit sera (AN-, HV- and SP sera) were determined with ToBI using the international reference serum with known antitoxin titre. In order to show the validity of the methods, the results were compared with those of the manufacturers/regulatory authorities and correlation coefficients were calculated. The correlation coefficients were r = 0.93 (AN sera), r = 0.73 (HV sera) and r = 0.85 (SP sera). All correlations were statistically significant. The specificity of the methods could be proved using heterologous antisera. The results of the ToBI were reproducible. Thus, the ToBI offers a suitable in vitro method for the determination of the antitoxin titre of rabbit antisera as an alternative to the toxin neutralisation in mice for potency testing of vaccines containing C. novyi type B alpha toxoid. 相似文献
19.
Two commercially available multicomponent clostridial vaccines were studied under field conditions in sheep. An eight-component vaccine designed for use in an initial dose volume of 5 ml with subsequent injections of 2 ml produced significantly better results than a seven-component vaccine designed for use in a dose volume of 2 ml. 相似文献
20.
Veschi JL Bruzzone OA Losada-Eaton DM Dutra IS Fernandez-Miyakawa ME 《Veterinary immunology and immunopathology》2008,125(1-2):198-202
Clostridium perfringens type D-producing epsilon toxin is a common cause of death in sheep and goats worldwide. Although anti-epsilon toxin serum antibodies have been detected in healthy non-vaccinated sheep, the information regarding naturally acquired antibodies in ruminants is scanty. The objective of the present report was to characterize the development of naturally acquired antibodies against C. perfringens epsilon toxin in goats. The levels of anti-epsilon toxin antibodies in blood serum of goat kids from two different herds were examined continuously for 14 months. Goats were not vaccinated against any clostridial disease and received heterologous colostrums from cows that were not vaccinated against any clostridial disease. During the survey one of these flocks suffered an unexpectedly severe C. perfringens type D enterotoxemia outbreak. The results showed that natural acquired antibodies against C. perfringens epsilon toxin can appear as early as 6 weeks in young goats and increase with the age without evidence of clinical disease. The enterotoxemia outbreak was coincident with a significant increase in the level of anti-epsilon toxin antibodies. 相似文献