Effect of the bacillus of Calmette-Guerin, Propionibacterium acnes and avridine as immunomodulators in antirabies vaccination of mice using the Fuenzalida-Palacios mouse brain vaccine

Using the laboratory mice, Fuenzalida-Palacios mouse brain human rabies vaccine was administered in groups of animals previously inoculated with rabies virus and then submitted to treatments with the immunomodulators onco-BCG, avridine and Plopionibacterium acnes. Humoral and cellular immune responses were evaluated through the macrophage inhibition factor (MIF), intra-pad inoculation (IPI) and serum neutralization (SN) tests and by the detection of gamma-interferon (IFN-gamma). The IPI test was not effective in detecting the response of delayed-type hypersensitivity, contrary to MIF, which showed the immune cellular response. Higher levels of IFN-gamma were observed in the groups of mice vaccinated and treated with avridine and P. acnes. Although immunomodulating activities have been detected, the use of adjuvants with the Fuenzalida-Palacios type vaccine in mice did not reveal any encouraging results. (C) 1999 Elsevier B.V. Ltd. All rights reserved.

Vaccine immune response and interference of colostral antibodies in calves vaccinated against rabies at 2, 4 and 6 months of age born from antirabies revaccinated females

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

EFFECTS of SELENIUM SUPPLEMENTATION on CATTLE ANTI-RABIES HUMORAL IMMUNE RESPONSE and LEVELS of SERUM SELENIUM and CORTISOL

This study evaluated the effect of different concentrations of selenium (Se) supplementation on cattle anti-rabies humoral immune response, serum Se concentrations and cortisol levels. Sixty uncastrated male Nelore calves from 10 to 12 months grazing on Brachiaria decumbens forage were studied. The animals were assigned to one of four groups (n = 15 each), which received non-supplemented diets (Gc) or supplemented with daily and individual Selenium ( Se) concentrations of 3.6 mg (G(3.6)), 5.4 mg (G(5.4)) or 6.4 mg (G(6.4)). The calves were immunized on day 0 with one dose of commercial liquid inactivated rabies vaccination. on days 15, 30, 60, 90 and 120, the cattle underwent the same stressing procedures used for vaccination in the corral. Cattle blood samples were collected after vaccination and stressing procedures to determine serum Se levels, rabies antibody titers and serum cortisol. Se levels were also determined in forage samples collected from the paddocks in which the cattle were held. Se concentration in B. decumbens was 0.04 mg of Se/kg dry matter. Baseline Se levels obtained on day 0 were higher in Gc than in G(5.4) and G(6.4) (P = 0.005). Serum Se levels decreased in Gc throughout the experiment (P < 0.004), increased in G(3.6) (P < 0.000) and G(5.4) (P < 0.000) and were kept high from day 60 on in group G(6.4) (P < 0.002). Rabies antibody titers did not differ among control and supplemented groups. However, 120 days after vaccination rabies antibody titers were kept above protective levels (>= 0.5 UI/mL) only in group G(3.6) (P < 0.00002), whereas they dropped in the other groups (P < 0.05). Serum cortisol levels did not differ among the experimental groups (P = 0.79), reached peak levels on day 90 and returned close to baseline levels on day 120. Se and cortisol levels were not markedly correlated. Serum cortisol and rabies antibody titers were correlated only in group G(6.4), on day 60 (R = 0.513; P = 0.05) and 120 (R = 0.644; P = 0.009). Serum Se and rabies antibody titers were correlated only in group G(6.4), on day 60 (R = -0.580; P = 0.023). In conclusion: a) the profile of Se variation is different among groups receiving different concentrations of this element; b) the supplementation dosage of 3.6 mg Se/animal/day is efficient to treat/prevent marginal Se deficiency; c) individual supplementation with daily concentrations of 3.6 mg Se enhances the maintenance of rabies antibody titers in cattle; d) individual supplementation with daily concentrations of 3.6; 5.4 and 6.4 mg Se are ineffective in reducing serum cortisol; e) repeated cattle handling in corrals stress animals that adapt to these procedures, although serum cortisol does not return to baseline levels by 120 days; and f) the stress generated by repeated management in cattle in the corral does not diminish antibody titers after vaccination against rabies.

Humoral immune response in dogs and cats vaccinated against rabies in southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of primovaccination and booster vaccination on serum cortisol and humoral immune response in cattle

The objective of this study was to evaluate the effect of one or two doses of the anti-rabies vaccination on the serum concentration of cortisol and the humoral immune response in cattle as well as the correlation between serum cortisol concentrations and the titers of rabies-neutralizing antibodies. Nelore cattle were randomly assigned to one of three groups, which were vaccinated with one dose of rabies vaccine (group GVSR, N = 15), two doses of rabies vaccine (group GVR, N = 15) or were not vaccinated (group Gc, N = 15). A commercial liquid inactivated rabies vaccine was used. The stressors imposed on the cattle were vaccination, corral handling and the presence of people. Blood samples were collected on days 0, 30 and 60 post-vaccination. Serum cortisol concentrations were determined using a solid-phase radioimmunoassay, and rabies antibody titers were determined using a serum neutralization test with BHK21 cells (RFFIT). Both serum cortisol concentrations and antibody titers increased after the second (booster) vaccination (P < 0.05). In all the groups, the serum cortisol concentrations increased after the cattle were handled in the corral (P < 0.05). No correlation was observed between the serum cortisol concentrations and the antibody titers with any treatment or on any observation day. In conclusion, booster vaccination is indispensable for primovaccinated cattle in achieving high and protective levels of rabies antibodies. Although booster vaccination and frequent cattle handling in corrals are stressors, the response is not strong enough to cause immunosuppression in cattle.

Comparison between a soluble antigen-based ELISA and IFAT in detecting antibodies against Babesia canis in dogs

O presente trabalho estudou um ensaio imunoenzimático (ELISA) indireto para a detecção de anticorpos anti-Babesia canis no soro de cães, tendo a Reação de Imunofluorescência Indireta (RIFI), como teste de referência O antígeno utilizado no ELISA do presente estudo consistiu em uma preparação antigênica solúvel de merozoítas B. canis e as diluições ótimas do antígeno, soros e conjugado foram determinadas por titulação em bloco, utilizando soros de referência positivos e negativos. A preparação antigênica solúvel de B. canis ótima foi de 10 µg.mL-1, com soros de referência positivos e negativos em uma única diluição de 1:100, e conjugado a 1:4.000. Um total de 246 amostras séricas foram colhidas em cães, durante a campanha de vacinação anti-rábica em Jaboticabal, São Paulo, Brasil e a presença de anticorpos anti-B. canis foi avaliada pelo ELISA e RIFI. Nestas condições, a média de absorbância dos soros de referência negativos foi de 0,129 ± 0,025, resultando em um ponto de corte de 0,323 (Nível de ELISA 3) e a média da absorbância dos soros de referência positivos foi de 2,156 ± 1,187. As amostras com sorologia positiva para B. canis por ELISA e RIFI foram 67,89% (n = 167) e 59,35% (n = 146), respectivamente. Os resultados obtidos sugerem que o ELISA descrito revelou-se um teste sorológico eficaz no diagnóstico da babesiose canina.

Ocorrência de anticorpos anti-Neospora caninum em cães da microrregião da Serra de Botucatu, Estado de São Paulo, Brasil

Neosporose é uma enfermidade parasitária causada pelo protozoário Neospora caninum reconhecido como importante causa de abortamento bovino e neuropatia canina. Considerando o isolamento de N. caninum e a sorologia freqüente em bovinos em nossa região, os objetivos do presente trabalho foram avaliar a ocorrência de anticorpos anti-N. caninum em cães da Microrregião da Serra de Botucatu, Estado de SãoPaulo, e sua associação ao sexo, idade e procedência quanto à zona urbana (exclusivamente cidade), rural (somente chácaras e sítios) e peri-urbana (acesso à zona urbana e rural) dos cães estudados. Foram analisados 963 cães, com ou sem raça definida, de ambos os sexos e diferentes idades, sem apresentação de qualquer sintomatologia clínica. Os animais foram selecionados aleatoriamente durante a campanha de vacinação anti-rábica da microrregião da Serra de Botucatu, no período de maio a setembro de 1998. O soro obtido dos animais foi avaliado por meio da Reação de Imunofluorescência Indireta (RIFI) utilizando como antígeno a cepa padrão NC-1 deN. caninum. Observaram-se 245 animais reagentes (25,4% de positividade), sendo 161 (27,5%) machos e, 84 (22,3%) fêmeas. Dos animais de zona urbana, rural e mista 223 (25,8%),11(16,9%) e 11(33,3%), respectivamente, foram reagentes à prova de RIFI. Todos os 11 municípios apresentaram cães soropositivos com valores de ocorrência que variaram de 8,9% a 53,5%. Observou-se percentual de positividade menor em cães até um ano (16,2%) quando comparados àqueles entre 1 a 4 anos e superior a 4 anos (28,4 % e 28,0%, respectivamente) que não apresentaram diferença entre si. Os resultados obtidos caracterizaram soropositividade para N. caninum em cães pertencentes a todos os municípios da Microrregião da Serra de Botucatu evidenciando a ampla distribuição do agente na região.

Avaliação da vacinação anti-rábica e da suplementação com probiótico na resposta imune humoral em bovinos

This study evaluated the humoral immune response of a new rabies vaccine developed by the Instituto Butantan (potency of 3.27 UI/ml) in primovaccinated cattle and the effect of probiotic on this response. Thirty-four 15-month old Nelore cattle were randomly divided into 2 groups (17 animals/group). All the animals were vaccinated on day 0 (zero) and then animals in one group received probiotic added to a mineral mixture (GP) while the others were given only the mineral mixture (GC). Blood samples were collected on days 0, 75 and 150 for rabies neutralizing antibodies titers by seroneutralization assay on BHK21 cells (RFFIT). Protective antibody titers (>= 0.5 UI/mL) were found in 82.4% of the animals from GP and in 76.5% of the animals from GC and no statistical difference (p>0.05) between antibody titers in GP and GC was detected on days 75 and 150. It was also observed that in both groups antibody titers was decreased on day 150 (p<0.01). In conclusion, the tested rabies vaccine promotes efficient soroconversion and keeps antibody levels in primovaccinated cattle, but probiotic does not affect the humoral anti-rabies immune response.

Avaliação da população canina da zona urbana do Município de Araçatuba, São Paulo, SP, Brasil

Planning control programs, for diseases such as rabies requires information on the size and structure of the dog and cat population. In order to evaluate the dog population of the urban area of Araçatuba city, S. Paulo State, Brazil, a survey was conducted using a questionnaire to interview members of households. Eighty-eight districts were visited (37,778 houses) and the interview was possible at 77.93% of these. Human population size evaluated was 113,157 inhabitants. Houses that owned animals represented 55.2%, 26,926 of the animals concerned were dogs and 5,755 were cats. Of the dogs, 56.64% were 1-4 year olds and males represented 56.2% of the total population. Dog: person ratio was estimated at 2.8 dogs to every 10 persons, almost 3 times the ratio hitherto estimated and used in the planning of rabies vaccination campaigns.

Investigação soroepidemiológica de leptospirose canina na área territorial urbana de Botucatu, São Paulo, Brasil

Leptospirosis was seroepidemiologically investigated in 775 dogs from Botucatu, state of Sao Paulo, in blood samples collected during the annual anti-rabies vaccination campaign. The samples were collected from 14 out of the 45 vaccination stations geographically distributed in five different municipal districts, with a territorial urban area of 31Km2. Samples were taken from 449 males and 326 females; 564 were of undetermined breed, and 211 were pedigree animals; ages ranged from 3 months to 20 years. Diagnosis included the microscopic serum agglutination tests using 12 Leptospira spp serovars. Serological results and epidemiological variables were compared using Goodman and chi-square tests, with χ=0.05. There were 119 (15.3%) positive samples for 11 serovars; the most important was canicola with 48 (40.3%), followed by pyrogenes 41 (34.5%). Statistical analysis showed significant difference for: breed, 17.7% positive in undetermined breeds and 9.0% in pedigrees; and sex, 18.4% positive in males and 11.0% in females. There was no statistically significant difference in relation to age with uniform distribution of positives.

Estimativa da febre maculosa em cães para a vigilância e motitoramento da antropozoonose no municipio de Botucatu, no Estado de São Paulo

Pós-graduação em Medicina Veterinária - FMVZ

Efeito das suplementações de selênio na resposta imune humoral anti-rábica, na concentração sérica de selênio e do cortisol em bovinos

Pós-graduação em Medicina Veterinária - FMVZ

Prevalence and geographical distribution of Toxoplasma gondii in dogs in the urban area of Botucatu, SP, Brazil

Toxoplasmosis is a worldwide zoonosis caused by Toxoplasma gondii, and can infect a wide variety of animals including humans. Domestic animals can be an important sentinel population for infection in the community. Occurrence of T. gondii infection was assessed in dogs in the urban area of Botucatu city, SP, Brazil. In the sample, 10% rate for error estimate, 95% confidence interval, and 5% significance level were established. Serum samples were collected from dogs during a rabies vaccination campaign, and were processed using modified agglutination test (MAT). Blood samples were collected from 670 dogs, with homogeneous distribution in five regions in the urban area, representing 3.74% of 17,910 animals vaccinated. In this sample, 17.3% (116/670) dogs (68 – 58.6% female and 48 – 41.4% male) were positive for T. gondii infection (p<0.03). Regarding age of the infected dogs 4.6% (4/88) were younger and 95.4% (84/88) were older than one year (p<0.01); the age of 28 positive animals were undetermined. The serum titers of anti-T. gondii antibodies were: 16 (69.8%; 81/116), 64 (13.8%; 16/116), 256 (15.5%; 18/116), and 1024 (0.9%; 1/116). Prevalence was distributed among the North 14.2% (19/134), South 18.0% (31/172), East 15.7% (19/121), West 21.6% (27/125), and Central 16.9% (20/118) regions of the municipality (p=0.5). In all these regions, females and dogs aged more than one year showed a higher occurrence of T. gondii infection (p<0.05).

Effect of vaccination and the immunomodulators bacillus of Calmette-Guerin, Avridine and Propionibacterium acnes on rabies in mice

Responses: of vaccination and treatment to immunomodulators against rabies in mice were evaluated through macrophage inhibition factor (MIF), intra-pad inoculation (IPI) and serum neutralization (SN) tests and by the detection of gamma-interferon (IFN-gamma). Onco-BCG, Avridine and Propionibacterium acnes were administered to groups of mice. Higher survival rates were found in animals treated with P. acnes. Lower levels of IFN-gamma were observed in the groups of infected and vaccinated mice. The IPI was not effective on detecting the response of delayed-type hypersensitivity. Vaccine induced in the infected animals a more intense response to MIF reaction. (C) 1998 Elsevier B.V. Ltd. All rights reserved.

Rabies infection and specific effect of vaccination in mice selected for high and low immunobiological parameters

Innate and acquired resistance to rabies infection was investigated in mice genetically selected for high (H) or low (L) antibody responsiveness from selections I, III and IV and in mice selected for maximal (AIRmax) or minimal (AIRmin) acute inflammatory reaction. These mouse lines were infected intramuscularly with different virus dilutions and the LD50 was determined. The HIII and HIV mouse lines were more susceptible than the LIII and LIV lines and the HI line showed a discrete but higher resistance than the LI line. Analysis of the interline (H x L) F1 hybrids from selections III and IV indicated different dominance effects on the resistant and susceptible phenotypes when the route of vaccination was changed. No differences were observed between the AIRmax and AIRmin mice, suggesting that inflammation plays a minor role in the resistance to rabies virus. The comparison of LD50 in mice vaccinated by distinct routes showed that the highest interline difference occurred after intramuscular vaccination (250-fold between H and L and 800-fold between F1 and L). These results indicate that different mechanisms may participate in acquired antirabies resistance