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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Sodium hypophosphite inhibition of Clostridium botulinum in pasteurized comminuted pork

Leifer, Arthur M. January 1983 (has links)
Sodium hypophosphite was evaluated for inhibition of growth and toxin production of Clostridium botulinum in a model meat system. Fresh comminuted pork was formulated to contain 0, 1000, or 3000 ppm sodium hypophosphite, with or without 50 ppm sodium nitrite, and 156 ppm sodium nitrite. The test formulations were inoculated with an equal mixture of 9 different strains of C. botulinum spores, vacuum packaged, pasteurized, and incubated for 60 days at 27°C. Packages were removed from incubation as swells developed and were analyzed for botulinal toxin by the mouse bioassay. In the first experiment, first toxic samples occurred at 5, 12, and 60 days of incubation for 0, 1000, and 3000 ppm sodium hypophosphite, respectively. Combinations of 1000 or 3000 ppm hypophosphite with nitrite delayed toxic swells by 17 and 14 days respectively, as compared to 6 days for 50 ppm nitrite alone. An experiment on the effects of sodium chloride on sodium hypophosphite inhibition showed that as the sodium chloride level was increased from O to 1.25 to 2.5%, hypophosphite inhibition was enhanced. For any sodium chloride level tested, increasing the hypophosphite concentration, caused a reduction in the rate of toxic swell formation. A combination of 2.5% salt, 50 ppm nitrite, and 3000 ppm sodium hypophosphite was the most effective combination tested. First toxic swell was delayed to day 24, and subsequent swells to day 33. The effects of various divalent cations on hypophosphite inhibition were studied. Cations produced no effect on sodium hypophosphite inhibition of C. botulinum. All experiments showed sodium hypophosphite to delay swell and toxin formation caused by Clostridium botulinum. / M.S.
22

Local Administration of Botulinum Toxin Type-B in the External Anal Sphincter of Horses Produces Transient Reduction of Peak Anal Pressure

Adam-Castrillo, David 25 July 2003 (has links)
Toxins produced by the Gram-positive bacteria Clostridium botulinum cause transient chemodenervation of mammalian muscle. The toxin binds to specific proteins within cholinergic presynaptic nerve terminals which regulate the release of acetylcholine in the synaptic space resulting is loss of muscle activation and function. Local injections with botulinum toxins are currently used in humans for the treatment of disorders that benefit from prolonged neuromuscular blockade such as strabismus, blepharospasm, focal dystonias, spasticity, tremors, and anal fissures. Injections with botulinum toxin type A into the internal or external anal sphincter cause relaxation of the anal canal and allow healing of chronic anal fissures. Perineal lacerations in mares, which occur during foaling often dehisce after surgical repair due to the high pressure across the incision resulting from accumulation of feces in the rectum. We hypothesized local injections of Clostridium botulinum type B toxin into the external anal sphincter could cause a decrease in anal pressures, thus reducing the incidence of dehiscence if used before surgical repair of perineal laceration in mares. The purpose of this project was to determine the effects of BTB injection in the external anal sphincter in normal horses. Our hypothesis was that local injection of BTB would result in transient reduction of anal tone without causing clinical side effects. Peak and resting anal sphincter pressures of horses were measured with a custom made rectal probe connected to a pressure transducer. Pressures were measured before treatment and after injection with Clostridium botulinum type B toxin (BTB) or saline. Dose titration with 500, 1000, 1500 and 2500 units of BTB was completed. The horses' physical changes, behavior, and anal pressure were recorded. Injection of 1000 units of BTB produced significant reduction in peak anal pressure from days 2 to 84 when compared to control animals (P<0.05). Maximal effect of the toxin was observed within the first 15 days after injections followed by a slow return to baseline over 168 days. Injection in the anal sphincter with 2500 units of BTB in one horse produced signs of depression, generalized weakness, and dysphagia for 14 days. Clinical side effects were not observed in horses after injections with 500, 1000, or 1500 units of BTB. In summary, local injections of botulinum toxin type-B in the external anal sphincter of horses caused transient relaxation of the anus and reduction of peak anal pressures. Systemic side effects were observed in one horse, which suggested a narrow dosage range to avoid toxicity. Further research to test the effects of botulinum toxin in clinical cases is needed to determine the full potential of this treatment modality. / Master of Science
23

An Economic Evaluation of Selected Treatments for Avian Botulism in Waterfowl on Utah Marshes, 1953-54

Smith, Donald A. 01 January 1955 (has links)
Each year thousands of western waterfowl succumb to disease, predators, mechanical injury and other decimating factors. Based on a review of records it is conservatively estimated that an average of 25,000 ducks have succumbed to botulism on western marsh areas annually. In a recent study, the United States Fish and Wildlife Services valued each duck and goose at $8.00 (McLeod, 1950). Applying this value to the estimated annual numerical loss, a total of $200,000 has been lost each season in mortality of western waterfowl from botulism. Control of this malady would reduce annual waterfowl and monetary losses. Prevention and cure are the only means of controlling botulism in wild ducks. At present, no economical preventative measure exists and control is based on curing stricken birds. The purpose of this study was to evaluate the cost of treatment and rate of recovery of birds stricken with botulism when treated by selected methods. The 4 treatments selected for evaluation were: (1) hospital inoculation, (2) fresh water, (3) field inoculation, and (4) no treatment or control. Research included a comprehensive evaluation of factors such as age, sex, species, body condition, degrees of affliction, reaction to various amounts of antitoxin, and reaction to selected treatment methods, thought to be pertinent in botulism control. This study was conducted during botulism outbreaks of 1953 and 1954, and was confined to state-owned marshlands of Utah.
24

Nitrate, nitrite and nitrosamine: contents and analyses in selected foods; effect of vitamin C supplementation on N-nitrosodimethylamine formation in humans; and an investigation of natural alternatives to nitrites as preservatives in cured meat products

Hsu, James Chun Hou, Chemical Sciences & Engineering, Faculty of Engineering, UNSW January 2009 (has links)
Dietary nitrite intake has been implicated in numerous gastrointestinal cancers in humans due to the formation of a group of carcinogens called N-nitroso compounds. The need to estimate their intake is vital in establishing at risk population and to monitor and perhaps one day manage their dietary intake. This is the first study to estimate nitrate and nitrite in selected vegetables, cured and fresh meat in Australian food supply using ion-paired reversed-phased HPLC. Nitrite content in meat products analysed ranged from 0 to 83.9 mg/kg in medallion beef and Frankfurt, respectively; nitrate content ranged from 18.7 mg/kg in minced beef to 142.5 mg/kg in salami. The nitrite content was below the maximum limit set by the Food Standards Australia and New Zealand. Nitrate content in selected vegetables ranged from 123 to 4850 mg/kg in Iceberg lettuce and English spinach, respectively; only minimal nitrite at 20 mg/kg was present in Gai choy, which was most likely due to bacterial contamination during storage. Based on the food consumption pattern of Australians, the dietary nitrite and nitrate intake from bacon were 1.51 and 3.42 mg per capita per day, which was below the Adequate Daily Intake set by the European Union Scientific Committee for food in 1995. Taking into considerations of oral nitrate reduction to nitrite and the endogenous nitrate formation, the upper extreme of dietary nitrite and nitrate intake in Australians were 44 and 2.4 times over the ADI, respectively. However, this does not take into effect of other dietary promoters and inhibitors. Eighteen healthy human volunteers were put on a low nitrate, nitrite and antioxidant diet for three days during which they were fed one serving of cured meat with and without 500 mg of vitamin C. Using GC-MS, N-nitrosodimethylamine was not detected in the urine before or after vitamin C supplementation, suggested that a diet low on nitrate and nitrite cannot produce NDMA and thus may reduce the risk of developing gastrointestinal cancers. Different extraction methods and combination of herbs and spices were demonstrated in vitro to show inhibition against B. cereus, Escherichia coli, Listeria monocytogenes, Salmonella Enteritidis and Staphylococcus aureus. In addition, autoclaved turmeric powder at 0.3 % (w/v), hot water extracted turmeric with ginger at 0.5 % and rosemary at 1.0 % showed growth inhibition against Clostridium sporogenes, which was used as a surrogate for Clostridium botulinum. The use of these combinations of herbs and spices may replace or at least reduce the use of nitrite as a preservative in cured meat products to prevent botulism and reduce dietary nitrite intake.
25

Nitrate, nitrite and nitrosamine: contents and analyses in selected foods; effect of vitamin C supplementation on N-nitrosodimethylamine formation in humans; and an investigation of natural alternatives to nitrites as preservatives in cured meat products

Hsu, James Chun Hou, Chemical Sciences & Engineering, Faculty of Engineering, UNSW January 2009 (has links)
Dietary nitrite intake has been implicated in numerous gastrointestinal cancers in humans due to the formation of a group of carcinogens called N-nitroso compounds. The need to estimate their intake is vital in establishing at risk population and to monitor and perhaps one day manage their dietary intake. This is the first study to estimate nitrate and nitrite in selected vegetables, cured and fresh meat in Australian food supply using ion-paired reversed-phased HPLC. Nitrite content in meat products analysed ranged from 0 to 83.9 mg/kg in medallion beef and Frankfurt, respectively; nitrate content ranged from 18.7 mg/kg in minced beef to 142.5 mg/kg in salami. The nitrite content was below the maximum limit set by the Food Standards Australia and New Zealand. Nitrate content in selected vegetables ranged from 123 to 4850 mg/kg in Iceberg lettuce and English spinach, respectively; only minimal nitrite at 20 mg/kg was present in Gai choy, which was most likely due to bacterial contamination during storage. Based on the food consumption pattern of Australians, the dietary nitrite and nitrate intake from bacon were 1.51 and 3.42 mg per capita per day, which was below the Adequate Daily Intake set by the European Union Scientific Committee for food in 1995. Taking into considerations of oral nitrate reduction to nitrite and the endogenous nitrate formation, the upper extreme of dietary nitrite and nitrate intake in Australians were 44 and 2.4 times over the ADI, respectively. However, this does not take into effect of other dietary promoters and inhibitors. Eighteen healthy human volunteers were put on a low nitrate, nitrite and antioxidant diet for three days during which they were fed one serving of cured meat with and without 500 mg of vitamin C. Using GC-MS, N-nitrosodimethylamine was not detected in the urine before or after vitamin C supplementation, suggested that a diet low on nitrate and nitrite cannot produce NDMA and thus may reduce the risk of developing gastrointestinal cancers. Different extraction methods and combination of herbs and spices were demonstrated in vitro to show inhibition against B. cereus, Escherichia coli, Listeria monocytogenes, Salmonella Enteritidis and Staphylococcus aureus. In addition, autoclaved turmeric powder at 0.3 % (w/v), hot water extracted turmeric with ginger at 0.5 % and rosemary at 1.0 % showed growth inhibition against Clostridium sporogenes, which was used as a surrogate for Clostridium botulinum. The use of these combinations of herbs and spices may replace or at least reduce the use of nitrite as a preservative in cured meat products to prevent botulism and reduce dietary nitrite intake.
26

Resposta humoral de bovinos para os toxóides botulínicos C e D

Curci, Vera Cláudia Lorenzetti Magalhães [UNESP] 19 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-19Bitstream added on 2014-06-13T18:48:10Z : No. of bitstreams: 1 curci_vclm_dr_jabo.pdf: 208355 bytes, checksum: b31da2026d8809c55818b68c4c8d77b7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foi avaliado pelo teste de ELISA indireto a resposta humoral para as toxinas botulínicas tipos C e D em animais vacinados com quatro diferentes produtos comerciais. Empregou-se duas vacinas bivalentes C e D (vacina 1 e vacina 2) e duas polivalentes contendo ainda os toxóides botulínicos tipos C e D (vacina 3 e vacina 4). Para análise foram realizadas seis colheitas de sangue ao longo do experimento, nos dias 0, 42, 75, 160, 250 e 342 após a vacinação. A imunidade passiva em bezerros até os 90 dias de idade, filhos de mães vacinadas com diferentes toxóides comerciais foram avaliados em 75 bezerros, agrupados de acordo com a vacina utilizada na mãe (B1, B2, B3 e B4). Para análise foram realizadas 3 colheitas de sangue, nos dias 5 (± 2), 45 e 90 dias após o nascimento. A avaliação da resposta humoral de bovinos vacinados em diferentes faixas etárias também foi realizada empregando-se uma vacina antibotulínica bivalente (C e D) comercial. Para análise, 90 bovinos foram divididos em 3 grupos de acordo com a faixa etária; animais com idade inferior a 2 anos, entre 2 e 5 anos e superior a 5 anos. Na avaliação da resposta humoral de animais vacinados com quatro diferentes produtos comerciais, para a toxina tipo C, as vacinas 1, 2, 3 e 4 não apresentaram diferenças significativas aos 42 dias da primeira dose. Aos 75 dias, a vacina 1, foi superior às vacinas 3 e 4, induzindo maior produção de anticorpos nos animais, porém não diferiu da vacina 2. Aos 160 dias houve queda na quantidade de anticorpos em todos os grupos, não havendo mais diferenças significativas entre as quatro vacinas testadas. Para a toxina tipo D, aos 42 dias da vacinação, não houve diferenças significativas entre as vacinas 1, 2 e 4, que apresentaram neste momento, valores superiores a vacina 3. No entanto, quando avaliadas aos 75 dias, a vacina 1 apresentou maior produção de anticorpos, diferindo... / To compare the efficiency of an “in house” ELISA test, standardized to measure antibody C and D from Clostridium botulinum, a survey to analysis four different commercial vaccines was conducted. The vaccines used were two commercial, bivalent botulinum containing subtypes C and D (vaccine 1 and vaccine 2) and other two polyvalent including subtypes C and D. The first trial was blood samples taken at 0, 42, 75, 160, 250 and 342 days after vaccination, whereas the booster was performed at day 42. The second trial, maternal antibodies were also measured taken blood samples from 1-3 months age steers obtained from vaccinated heifers with the same vaccines described above, and divided into four different groups (B1, B2, B3, B4). The blood samples were taken at days 5, 45 and 90 after birth. Third and last trial was humoral response from vaccinated cattle with different age evaluation performed using the commercial Clostridium botulinum vaccine subtype C and D. For this purpose, 90 animals never vaccinated, were divided into 3 groups: 1 - 2 years old; 2 – animals aged between 2 and 5 years old; 3 – animals 5 years old. The blood samples were taken 30 days after vaccination after second dose of the vaccine. From the first trial, no significant difference was observed when subtype C was search in sera from animals at 42 days after vaccination. However, at 75 days after vaccination, vaccine 1 was able to induce higher levels of antibodies when compared to vaccine 3 and 4. The antibody level was declining after 160 days post vaccination. For subtype D antigen, at 42 days after vaccination, no differences could be observed. However, at 75 day after vaccination, higher levels of antibodies were observed from animals vaccinated with vaccine 1. Comparing the bivalent vaccines, these were able to induce higher antibodies levels at 75 days after vaccination (toxoid C). In addition, the same... (Complete abstract click electronic access below)
27

Aspectos epidemiológicos, clínicos, patológicos e laboratoriais do botulismo em bovinos no estado de Santa Catarina / Epidemiologival, clinical, pathological and laboratory findings of botulism in cattle in the State of Santa Catarina

Veronezi, Luciane Orbem 11 November 2009 (has links)
Made available in DSpace on 2016-12-08T16:24:17Z (GMT). No. of bitstreams: 1 PGCA09MA137.pdf: 7646125 bytes, checksum: aa6f9bf26c4235333e8d6e22c4835a6a (MD5) Previous issue date: 2009-11-11 / The study was carried out through the epidemiological, clinical, pathological and laboratory findings of botulism in cattle in the state of Santa Catarina, during the period from 1987 to 2008. The data were obtained through information from the files of the Department of Animal Pathology CAV/UDESC and in the properties which the disease continued to occur. In properties with the botulism associated phosphorus deficiency cattle, the animals were kept on native pastures, in most cases, located in the Planalto Serrano. The disease occurred mainly in the summer months, when cows with calf without mineral supplementation and that were not vaccinated against botulism. In the farms visited, there were several bones of corpses scattered in the pastures. Eight outbreaks of botulism were studied from 2006 to 2008, including seven cases related to phosphorus deficiency and osteophagia, and one case associated with oat pasture fertilized with incomplete decomposed carcasses of pigs and poultry. In all outbreaks clinical signs consisted of paresis, progressive paralysis and recumbency followed by death. At necropsy there were no lesions, but bone fragments were found mixed with the contents of the reticulum of two cattle. On histological examination, significant lesions were not observed. In the microbiological analisys performed in the samples collected from seven outbreaks C. botulinum was isolated. In the botulism associated phosphorus deficiency, botulinum toxin type C was detected from the intestinal contents of cattle and type D on samples collected from bone and soil. In the botulism associated with contamineted feed, was detected spores of C.botulinum type D isolated from samples of compost, soil and bones of carcasses scattered in the pasture. The diagnosis of botulism was established through the analysis of epidemiological, clinical and pathological findings associated with the detection of toxin present in outbreaks studied / O trabalho foi realizado através de estudo dos aspectos epidemiológicos, clínicos, patológicos e laboratoriais do botulismo em bovinos no Estado de Santa Catarina, durante os anos de 1987 a 2008. Os dados foram adquiridos através de informações obtidas dos arquivos do Setor de Patologia Animal CAV/UDESC e nas propriedades em que a enfermidade continuou a ocorrer. Nas propriedades com botulismo associado à deficiência de fósforo, os bovinos eram mantidos em campos nativos, na maioria dos casos, localizados na região do Planalto Serrano. A doença manifestou-se principalmente nos meses de verão, em vacas com terneiro ao pé, sem suplementação mineral e que não eram vacinados contra botulismo. Nas propriedades visitadas foram observados inúmeros ossos de cadáveres espalhados nas pastagens. Oito surtos de botulismo foram acompanhados no período de 2006 a 2008, sendo sete deles relacionados à carência de fósforo e osteofagia e um associado à pastagem de aveia adubada com compostagem incompleta de carcaças de suínos e aves. Em todos os surtos os sinais clínicos consistiam em paresia, paralisia progressiva, decúbito seguido de morte. Á necropsia não foram evidenciadas lesões, porém fragmentos de ossos foram encontrados misturados ao conteúdo do retículo de dois bovinos. No exame histológico não foi observado lesões significativas. Na análise microbiológica das amostras coletadas de sete surtos foi isolado C. botulinum. No botulismo associado a deficiência de fósforo foi detectada toxina botulínica tipo C em conteúdo intestinal de um bovino e tipo D a partir de ossos e amostras de solo coletado. No botulismo associado a alimentos contaminados, foi detectados esporos do Clostridium botulinum tipo D nas amostras da compostagem, de solo e ossos das carcaças espalhadas na pastagem. O diagnóstico de botulismo foi estabelecido através da análise dos aspectos epidemiológicos, clínicos e patológicos associado à detecção da toxina botulínica presente nos surtos acompanhados
28

Estudo da cinetica de acidificação de palmito em conserva / Study of the kinetic of acidification in canned heart of palm

Quast, Ernesto, 1975- 14 August 2018 (has links)
Orientador: Flavio Luis Schmidt / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-14T15:45:20Z (GMT). No. of bitstreams: 1 Quast_Ernesto_M.pdf: 1820232 bytes, checksum: 30904cbd0aa1ec3f045d21ff606867b5 (MD5) Previous issue date: 2009 / Resumo: A garantia da segurança microbiológica de alimentos prontos para o consumo é essencial para a sua comercialização. Alimentos sensíveis ao calor, como o palmito, podem ser conservados com tratamentos térmicos brandos, adição de conservantes químicos, diminuição do pH ou por métodos combinados. Aliando-se a pasteurização com a acidificação adequada é possível impedir a germinação de Clostridium botulinum. A difusão de ácido até o interior do tecido vegetal deve ocorrer durante um intervalo de tempo que não seja suficiente para permitir a germinação de esporos, multiplicação das células e conseqüente formação de toxina botulínica. A cinética de acidificação dos diferentes tecidos que compõe o tolete de palmito foi estudada, observando-se uma diferença significativa do tempo necessário para o abaixamento do pH dos mesmos. O tempo para a acidificação de toletes de com diferentes comprimentos também foi avaliado, sendo observado o desenvolvimento de esporos de C. sporogenes (PA3679) em toletes de palmito pupunha com comprimento maior que 3 cm, com pH de equilíbrio de 4,41, indicando a possibilidade da formação de toxina botulínica em toletes com tamanho comercial em pH de equilíbrio = 4,5 desde que exista a presença de esporos de C. botulinum no seu interior. O palmito não é um meio rico para o desenvolvimento de esporos de PA3679, fato observado pela não germinação destes esporos em suspensão de palmito triturado e misturado, com pH < 5,2. Isto mostra que o pH no interior do tolete deve atingir pH < 5,2 para impedir o desenvolvimento de esporos microbianos / Abstract: Ready to eat food must have their food safety guaranteed. Heat sensible food, such as heart of palm, can be preserved using mild heat treatment, chemical preservatives addition and acidification or combined methods. Germination of Clostridium botulinum can be inhibited by combining mild heat treatment and lowering of pH. The diffusion of the acid to the interior of the vegetable tissue must be fast enough not to permit spores germination, multiplication of the vegetative cells and consequent botulinum toxin formation. Study of the acidification of heart of palm showed a significant difference between the tissues regarding to the time necessary for lowering the pH. Hearts of palm Bactris gasipaes were evaluated and were observed the growth of C. sporogenes (PA3679) spores in stems with length larger than 3 cm in equilibrium pH of 4.41, indicating the possibility of botulism toxin formation in commercial heart of palm preserves with pH = 4.5 if spores of C. botulinum are present in the vegetable tissue. Heart of palm is not rich growing medium as observed that spores of PA3679 did not grow in suspension of triturated heart or palm with pH < 5.2. This fact shows that pH in the interior of heart of palm should reach pH < 5.2 to inhibit bacteria spores development / Mestrado / Mestre em Tecnologia de Alimentos
29

The Foods and Feeding Habits of Botulism Intoxicated and Healthy Waterbirds on the Bear River Refuge, Utah, with Emphasis on the American Avocet and Blacknecked Stilt

Wilson, George W. 01 May 1973 (has links)
Primary objectives of this study were: (1) to compare the food habits of healthy and botulism intoxicated American avocets and blacknecked stilts for qualitative and quantitative differences, (2) to determine .which invertebrates found in the tracts of intoxicated and healthy birds contained type C toxin, and (3) to explain apparent susceptibilities among different sexes, ages and species of birds. Based on percent utilization and occurrence of food items in the esophagus , the diets of healthy and intoxicated birds were similar. However, intoxicated avocets consumed higher proportions of Gastropoda and intoxicated stilts more Hydrophilidae larvae than did healthy birds. Because of similarities in diets of healthy and intoxicated birds, birds probably became intoxicated from eating randomly toxic foods and not because of differences in diet or food preference. Examinations of esophageal contents of avocets and stilts better described recently consumed food items than did examinations of gizzard contents. Soft-bodied invertebrates were rendered unidentifiable in the gizzard. The esophageal contents of juvenile avocets and stilts contained greater proportions of animal matter than did those of adults. Only three of 86 food samples analyzed were definitely positive for type C botulism toxin. These were: one sample of Tendipedidae larvae and two of pooled gizzard contents which included fragments of Corixidae, Hydrophilidae adults, seeds and vegetative fibers. Only three of 86 food samples analyzed were definitely positive for type C botulism toxin. These were: one sample of Tendipedidae larvae and two of pooled gizzard contents which included fragments of Corixidae, Hydrophilidae adults, seeds and vegetative fibers.
30

Resposta humoral de bovinos para os toxóides botulínicos C e D /

Curci, Vera Cláudia Lorenzetti Magalhães. January 2008 (has links)
Orientador: Iveraldo dos Santos Dutra / Banca: Júlio Cesar de Freitas / Banca: Tereza Cristina Cardoso da Silva / Banca: Raul José Silva Girio / Banca: Samir Issa Samara / Resumo: Foi avaliado pelo teste de ELISA indireto a resposta humoral para as toxinas botulínicas tipos C e D em animais vacinados com quatro diferentes produtos comerciais. Empregou-se duas vacinas bivalentes C e D (vacina 1 e vacina 2) e duas polivalentes contendo ainda os toxóides botulínicos tipos C e D (vacina 3 e vacina 4). Para análise foram realizadas seis colheitas de sangue ao longo do experimento, nos dias 0, 42, 75, 160, 250 e 342 após a vacinação. A imunidade passiva em bezerros até os 90 dias de idade, filhos de mães vacinadas com diferentes toxóides comerciais foram avaliados em 75 bezerros, agrupados de acordo com a vacina utilizada na mãe (B1, B2, B3 e B4). Para análise foram realizadas 3 colheitas de sangue, nos dias 5 (± 2), 45 e 90 dias após o nascimento. A avaliação da resposta humoral de bovinos vacinados em diferentes faixas etárias também foi realizada empregando-se uma vacina antibotulínica bivalente (C e D) comercial. Para análise, 90 bovinos foram divididos em 3 grupos de acordo com a faixa etária; animais com idade inferior a 2 anos, entre 2 e 5 anos e superior a 5 anos. Na avaliação da resposta humoral de animais vacinados com quatro diferentes produtos comerciais, para a toxina tipo C, as vacinas 1, 2, 3 e 4 não apresentaram diferenças significativas aos 42 dias da primeira dose. Aos 75 dias, a vacina 1, foi superior às vacinas 3 e 4, induzindo maior produção de anticorpos nos animais, porém não diferiu da vacina 2. Aos 160 dias houve queda na quantidade de anticorpos em todos os grupos, não havendo mais diferenças significativas entre as quatro vacinas testadas. Para a toxina tipo D, aos 42 dias da vacinação, não houve diferenças significativas entre as vacinas 1, 2 e 4, que apresentaram neste momento, valores superiores a vacina 3. No entanto, quando avaliadas aos 75 dias, a vacina 1 apresentou maior produção de anticorpos, diferindo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: To compare the efficiency of an "in house" ELISA test, standardized to measure antibody C and D from Clostridium botulinum, a survey to analysis four different commercial vaccines was conducted. The vaccines used were two commercial, bivalent botulinum containing subtypes C and D (vaccine 1 and vaccine 2) and other two polyvalent including subtypes C and D. The first trial was blood samples taken at 0, 42, 75, 160, 250 and 342 days after vaccination, whereas the booster was performed at day 42. The second trial, maternal antibodies were also measured taken blood samples from 1-3 months age steers obtained from vaccinated heifers with the same vaccines described above, and divided into four different groups (B1, B2, B3, B4). The blood samples were taken at days 5, 45 and 90 after birth. Third and last trial was humoral response from vaccinated cattle with different age evaluation performed using the commercial Clostridium botulinum vaccine subtype C and D. For this purpose, 90 animals never vaccinated, were divided into 3 groups: 1 - 2 years old; 2 - animals aged between 2 and 5 years old; 3 - animals 5 years old. The blood samples were taken 30 days after vaccination after second dose of the vaccine. From the first trial, no significant difference was observed when subtype C was search in sera from animals at 42 days after vaccination. However, at 75 days after vaccination, vaccine 1 was able to induce higher levels of antibodies when compared to vaccine 3 and 4. The antibody level was declining after 160 days post vaccination. For subtype D antigen, at 42 days after vaccination, no differences could be observed. However, at 75 day after vaccination, higher levels of antibodies were observed from animals vaccinated with vaccine 1. Comparing the bivalent vaccines, these were able to induce higher antibodies levels at 75 days after vaccination (toxoid C). In addition, the same... (Complete abstract click electronic access below) / Doutor

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