A mussarela de leite de búfala, principal queijo obtido a partir desse leite no Brasil, é um produto praticamente novo no mercado, com alta aceitação pelos consumidores e excelentes perspectivas. Seguindo tecnologia de produção tradicional italiana, caracteriza-se pela intensa manipulação durante a sua elaboração. No presente trabalho, avaliou-se a qualidade microbiológica de duas marcas comerciais de queijo mussarela de leite de búfala, sendo uma das marcas comercializada em embalagem com soro (A) e a outra em embalagem sem soro e a vácuo (B), adquiridas no comércio varejista da cidade de Piracicaba/SP. As análises microbiológicas compreenderam a determinação do NMP de coliformes totais e fecais, a pesquisa de Listeria spp., a contagem de Staphylococcus coagulase-positiva e a pesquisa de Salmonella spp. Com base nos resultados obtidos, pode-se afirmar que as duas marcas analisadas encontram-se em acordo com os padrões microbiológicos legais vigentes. No entanto, pôde-se notar que a qualidade microbiológica dos queijos comercializados em embalagem com soro mostrou-se inferior à dos oferecidos ao consumo em embalagem sem soro e a vácuo. / Buffalo mozzarella cheese, main cheese obtained from buffalo milk in Brazil, is practically a recent product in the market, showing high acceptance by consumers and excellent perspectives. Following traditional italian production tecnology, this cheese is intensely manipulated during its manufacture. In this study, the microbiology quality of two commercial brands of buffalo mozzarella cheese was evaluated, being one of the brands presented in bag with whey (A) while the other one is presented in bag without whey and under vacuum (B). The samples were acquired in the Piracicaba city commerce. Microbiology analysis comprehended the determination of the MPN of total and fecal coliforms, the Listeria spp. presence / absence, the coagulase-positive Staphylococcus accounting and the Salmonella spp. presence / absence. Based on the analysis results, both brands are according to current legal microbiology standards specifications. However, the microbiology quality of the cheeses packed in bag with whey was lower than the microbiology quality of those offered in bag without whey and under vacuum.

Genetic variation, structure and dispersal among Cape buffalo populations from the Hluhluwe-Imfolozi and Kruger National Parks of South Africa Barend Jacobus (Ben) Greyling Doctor of Philosophy (Zoology) Department of Zoology and Entomology Supervisor: Prof. Armanda Slager-Bastos Co-supervisor: Dr. Pim van Hooft 2007 The research reported on in this thesis is aimed at quantifying and qualifying, using a molecular genetics approach, some of the factors that influence the population dynamics of Cape buffalo (Syncerus caffer caffer) from the Kruger National Park (KNP) and Hluhluwe-imFolozi park (HiP) in South Africa. Prior to large-scale genotyping of animals sampled from these parks, a high-throughput, cost- and time-effective profiling system was developed. The system, based on a panel of 17 microsatellites (Msats), was found to be quite suitable for the intended application, since it uncovered substantial genetic variation, while exclusion probabilities were in excess of 0.999 and a random match probability of 6.5 x 10-17 was obtained. Inter-population level analyses revealed that the two populations were significantly differentiated (Msat data: FST = 0.159; mtDNA data: FST = 0.275), while little or no differentiation could be demonstrated among most herds and subpopulations. It seems that while drift has played a major role in divergence of the two populations, gene flow is the primary driving force behind the maintenance of genetic variation among herds and subpopulations. A striking feature was that HiP exhibited significant lower levels of genetic variation than KNP, which is reflected by the fact that a mere 4 haplotypes could be found in HiP compared to 34 identified in KNP. The absence of geographic partitioning and small genetic distances separating the haplotypes may be attributed to genetic contact between the respective populations in the distant past. The reduced levels of genetic variation in HiP may be the remnants of the rinderpest bottleneck. HiP also displayed signals of a population contraction, while KNP is in equilibrium and seems to have retained substantial levels of genetic variation. HiP also experienced a steady decline in genetic variation from 1986 to 2004, while sex-biased dispersal was less pronounced in HiP than in KNP, possibly due to the lack of mtDNA diversity and the small size of the park. The results presented here provide valuable baseline information for making conservation management decisions from a genetic point of view. / Thesis (PhD (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

Foot-and-mouth disease (FMD) is an economically devastating picornaviral disease affecting over 40 species of cloven-hoofed animals. The virus occurs as seven immunologically distinct serotypes which are characterized by high levels of intra- and intertypic variation. The three South African Territories (SAT) serotypes 1-3 are endemic to sub-Saharan Africa, a region where the epidemiology of the disease is particularly complex due to the presence of six of the seven serotypes, the role of wildlife in virus maintenance and the apparently higher levels of variation in the endemic serotypes. These factors make it imperative to establish methods suited to elucidating the regional epidemiology. One of the integral parts of this process is the genetic characterization of regionally representative viruses in order to assess the variation in the field and to clarify the role of wildlife. Nucleotide sequence data and methods suited to studying the SAT-types are however limited. A first priority was therefore to establish a PCR-based nucleotide sequencing technique targeting the highly immunogenic and phylogenetically informative 1D genome region encoding the VP1 protein. The screening of multiple serotypes and subtypes prevalent on the African continent confirmed that this method was robust and well-suited to molecular epidemiological studies in the southern Africa region. The method was first applied in the characterization of FMD virus recovered from the reproductive tract of free-living African buffalo in the Kruger National Park. Nucleotide sequencing assisted in authentication of the results and indicated that carrier status was likely, but it was not possible to unequivocally demonstrate persistent infection of FMDV. In a separate study, the role of impala antelope (Aepyceros melampus) in the epidemiology of the disease in South Africa was assessed. Genetic characterization of impala and African buffalo (Syncerus caffer) viruses collected over an eleven year period confirmed that inter-species transmission occurred on several occasions and that virus can persist in impala populations for more than 12 months. Inter-species transmission and investigation of the possible mechanisms facilitating virus transmission from persistently infected buffalo focussed on the Kruger National Park in South Africa. In order to ensure regional relevance the study was broadened to incorporate buffalo populations throughout southern Africa. Viruses of the three SAT-types recovered from diverse African buffalo populations were therefore characterized. The results reveal that independently evolving viral lineages occur in distinct geographical regions for each of the SAT-types examined and that the levels of intratypic variation are in the order of 52 - 55 % on nucleotide level across the genome region characterized. Given the strict locality-specific grouping of buffalo viruses the likely usefulness of this database for tracing the origin and course of contemporary and historical SAT-type outbreaks was investigated. Molecular epidemiological studies conclusively show that buffalo are indeed the ultimate source of infection for susceptible cloven-hoofed animals occurring in close proximity, that interspecies transmission occurs between cattle and antelope and that trans-boundary transmission of virus remains a threat to disease security in southern African countries. / Thesis (PhD (Microbiology))--University of Pretoria, 2007. / Microbiology and Plant Pathology / unrestricted

The effect of trampling on vegetation and soil, as a result of recreational pressure, was studied in the Buffalo campground of the Targhee National Forest, Idaho. Site deterioration was most evident in the forty-two year old site. The tree stand had matured, but there were few young trees and tree reproduction had been reduced to ten seedlings per acre for Pinus contorta. Only two shrub species were sampled with a combined population of eight individuals per acre. Most of the grass species had been seeded; forbs provided 20% of the ground cover, 13% was bare ground and 71% litter. The soil had become compacted, and a hard-pan had formed. Similar deterioration was found in the six-year old site, but to a lesser degree. The year-old site was most similar to the control area, but site deterioration had occurred. It is difficult to reverse or halt site deterioration and still maintain the area as a public facility. Seeding and rest-rotation could improve the oldest site; younger sites could be maintained by restrotation, to allow existing vegetation to re-stock the depleted areas.

BACKGROUND:In a globalized word, prevention of infectious diseases is a major challenge. Rapid detection of viable virus particles in water and other environmental samples is essential to public health risk assessment, homeland security and environmental protection. Current virus detection methods, especially assessing viral infectivity, are complex and time-consuming, making point-of-care detection a challenge. Faster, more sensitive, highly specific methods are needed to quantify potentially hazardous viral pathogens and to determine if suspected materials contain viable viral particles. Fourier transform infrared (FTIR) spectroscopy combined with cellular-based sensing, may offer a precise way to detect specific viruses. This approach utilizes infrared light to monitor changes in molecular components of cells by tracking changes in absorbance patterns produced following virus infection. In this work poliovirus (PV1) was used to evaluate the utility of FTIR spectroscopy with cell culture for rapid detection of infective virus particles.RESULTS:Buffalo green monkey kidney (BGMK) cells infected with different virus titers were studied at 1 - 12 hours post-infection (h.p.i.). A partial least squares (PLS) regression method was used to analyze and model cellular responses to different infection titers and times post-infection. The model performs best at 8 h.p.i., resulting in an estimated root mean square error of cross validation (RMSECV) of 17 plaque forming units (PFU)/ml when using low titers of infection of 10 and 100 PFU/ml. Higher titers, from 103 to 106 PFU/ml, could also be reliably detected.CONCLUSIONS:This approach to poliovirus detection and quantification using FTIR spectroscopy and cell culture could potentially be extended to compare biochemical cell responses to infection with different viruses. This virus detection method could feasibly be adapted to an automated scheme for use in areas such as water safety monitoring and medical diagnostics.

L’augmentation depuis une trentaine d’années des maladies infectieuses dites émergentes ou ré-émergentes chez l’homme, causées à plus de 70% par des pathogènes issus d’espèces hôtes animales (i.e. Ebola, SIDA), stimule l’étude de systèmes éco-épidémiologiques à l’interface entres populations humaines et animales (i.e. sauvages et/ou domestiques).Le contact entre hôtes est un phénomène important dans l’étude de ces systèmes car il permet la transmission des pathogènes entre individus et la diffusion de maladie au sein et entre populations. Nous avons choisi la maladie de la fièvre aphteuse comme modèle d’étude de la transmission de pathogènes des populations sauvages vers les populations domestiques. Le buffle africain (Syncerus caffer) étant le réservoir présumé de cette maladie fortement contagieuse, nous nous sommes interrogés sur les conditions de transfert au bétail (Bos taurus et Bos indicus) du virus aphteux aux frontières de trois parcs nationaux africains qui constituent des interfaces entre espaces anthropiques et protégés perméables aux mouvements d’animaux. Dans le cadre de ce doctorat 4 protocoles ont été mis en place entre 2010 et 2011 au Zimbabwe. Premièrement, des colliers GPS (Global Positionning System) ont été déployés sur des bovins sauvages/domestiques pour décrire leurs déplacements dans le paysage et quantifier les contacts interspécifiques. Des colliers furent également posés sur l’une des espèces prédatrices de ces ongulés: le lion (Panthera leo). L’intégration de la guilde des prédateurs nous a permis d’estimer les modifications de l’utilisation de l’espace par les herbivores en réponse à la présence de carnivores et les conséquences en termes de contacts et de transmission interspécifique de pathogènes. Deuxièmement, un suivi longitudinal sérologique sur le bétail a complété le protocole télémétrique avec des prélèvements répétés sur des individus marqués selon le cycle saisonnier. Troisièmement, les contacts au sein des populations de bovins domestiques ont été caractérisés par des enquêtes auprès des éleveurs. Quatrièmement, le rôle potentiel de la diversité des hôtes sur le risque infectieux d’un écosystème a été exploré par l’estimation de densité de macro-parasites dans le paysage selon une variation de la gamme d’hôtes potentiels (i.e. (i) sauvages, (ii) sauvages et domestiques et (iii) uniquement domestiques).Nos résultats montrent que (1) les taux d’interaction interspécifiques, estimés par télémétrie, varient entre sites et présentent une saisonnalité prononcée (i.e. pic saison sèche chaude). (2) La distribution des ressources conditionne la périodicité et la distribution de ces contacts dans les différents compartiments du paysage. (3) La fréquence des incursions du bétail dans un espace protégé ainsi que les taux de contacts avec les buffles influencent positivement la probabilité d’acquisition d’anticorps anti-aphteux chez le bétail. La probabilité de perte d’anticorps est également fonction du niveau d’interaction avec les buffles mais selon une relation négative. (4) La densité du réseau d’interaction intra-spécifique domestique influence positivement l’incidence sérologique de la fièvre aphteuse. (5) La présence de prédateurs supérieurs dans le paysage permettrait de limiter les incursions du bétail dans les espaces protégés et diminuerait la probabilité d’infection par les populations d’hôtes sauvages. (6) Enfin les densités de macro-parasites dans la végétation sont supérieures dans des espaces communaux sans interaction avec les populations sauvages et où la richesse spécifique des hôtes est plus faible. Les résultats de cette étude sur la transmission interspécifique de pathogènes entre populations sauvages et domestiques dans les écosystèmes tropicaux ouvrent des champs de réflexion encore largement inexplorés, notamment sur l’évolution de la virulence et des modes de transmission des pathogènes ayant comme hôtes des populations sympatriques sauvages et domestiques. / Emerging or re-emerging diseases in human populations have increased over the last thirty years. Since 70% of such diseases are caused by pathogens originating from animal hosts (i.e. Ebola, AIDS, and avian influenza), this increase has prompted the study of eco-epidemiological systems that occur at the interface between human and animal populations (i.e. wild and/or domestic). Contacts between hosts are particularly important factors in these systems since they result in pathogen transmission among individuals and, therefore, disease diffusion within and among populations. We used foot-and-mouth disease (FMD) as a model to study pathogen transmission from wild to domestic populations. As the African buffalo (Syncerus caffer) is the presumed reservoir of this highly contagious disease, we examined the conditions in which the virus was transmitted to cattle sensitive to the disease (Bos taurus and Bos indicus) at the borders of African national parks; these areas are interfaces between anthropogenic and protected areas in which animals can move freely.In the context, 4 protocols were implemented between 2010 and 2011 in Zimbabwe. First, GPS (Global Positioning System) collars were placed on cattle and buffalo in order to describe and analyze their movements across the landscape as well as to quantify interspecific contacts. In one of the study sites, collars were attached to one of the predators of these ungulates: the lion (Panthera leo). By integrating the predator guild into our telemetry protocols, we could examine the potential changes in spatial use by cattle and buffalo in response to predator presence and their consequences for contact dynamics and interspecific pathogen transmission. Second, a longitudinal serological survey was conducted in which tagged individuals were sampled repeatedly over the course of different seasons. Third, to characterize contacts within the domestic host population, interviews were conducted with cattle owners regarding their husbandry practices across seasons. Fourth, to describe the potential role of host diversity in ecosystem infection risks, macroparasite density (i.e. ticks) was estimated for landscape compartments that contrasted in terms of potential hosts present (i.e. (i) wild, (ii) domestic and wild, and (iii) domestic only).Our study primarily shows the following results. (1) Interspecific interaction rates, as estimated by telemetry, vary between sites and have a pronounced seasonality (peak occurs during the hot dry season). (2) Resource distribution (i.e. water and grazing areas) seems to condition the frequency and distribution of these contacts in the different landscape compartments. (3) Cattle incursion frequencies into protected areas and the frequency and intensity of contact with buffalo significantly positively affect the probability of foot-and-mouth antibody acquisition in cattle. The probability of antibody loss in cattle is also a function of diminished rates of interaction with buffalo. (4) Intraspecific interaction densities positively influence FMD serological incidence in cattle. (5) Top predator presence in the landscape could limit cattle incursion into protected areas and reduce the likelihood of their being infected by wild host populations. (6) Finally, the estimated densities of macroparasites in the vegetation were higher in communal spaces where there was no interaction with wild hosts and where host species richness was weak.The results of this study on the interspecific transmission of pathogens between wild and domestic populations in tropical ecosystems encourage the exploration of research topics that are still largely unexplored, including the evolution of virulence transmission modes of pathogens hosted by sympatric wild and domestic populations.

Introdução: Com o crescente aumento de hipersensibilidades alimentares e doenças do trato gastrintestinal, o mercado de lácteos vem ampliando a variedade de produtos com diferentes matrizes alimentares. A expansão da criação bubalina no país incentivou o desenvolvimento de produtos derivados do leite bubalino, os quais contém propriedades nutricionais e físico-químicas diferentes da matriz bovina, ganhando maior participação no atual mercado consumidor. As bactérias probióticas são capazes de modular a resposta imune inata e adaptativa de acordo com a cepa, matriz e tecnologia empregada no desenvolvimento do produto. Assim como a modulação imune também pode ser alterada de maneira epigenética por interferência da matriz alimentar empregada. Método: Sendo os microRNAs de leite e leite bubalino homólogos aos do leite humano, foram preparados leites fermentados em matriz bovina e bubalina usando a cepa Bifidobacterium animalis subsp. lactis HN019 com o intuito de identificar a diferença entre o perfil físco-químico, viabilidade da cepa probiótica utilizada, e presença de microRNAs imunomoduladores homólogos com o intuito de verificar se as modificações sofridas nas matrizes bovina e bubalina durante o processo de fermentação por bactérias probióticas teria interferência na presença de miRNAs imunomoduladores e na resposta imune de mucosa. Conclusão: Os resultados obtidos mostraram maior teor de proteínas, sólidos totais e gordura na matriz bubalina em relação a matriz bovina. Enquanto na matriz bubalina fermentada apresentou maior teor de ácidos graxos comparado a matriz bovina fermentada, o perfil de acidificação e pós acidificação foi semelhante em ambas as matrizes. O processo de fermentação em matrizes lácteas distintas, proporcionou modificação do perfil celular imunológico na mucosa intestinal, porém levou a destruição dos miRNAs do processamento térmico, identificando que esta modificação da resposta imune independe dos microRNAs homólogos estudados. / Introduction: With the increasing increase of food hypersensitivity and diseases of the gastrointestinal tract, the dairy market has been increasing the variety of products with different food matrices. The expansion of buffalo breeding in the country encouraged the development of products derived from buffalo milk, which contain different nutritional and physicochemical properties of the bovine matrix, gaining greater participation in the current consumer market. Probiotic bacteria are able to modulate the innate and adaptive immune response according to the strain, matrix and technology employed in product development. Just as immune modulation can also be altered epigenetically by interference of the food matrix employed. Method: Since the microRNAs of milk and buffalo milk were homologous to those of human milk, fermented milks were prepared in bovine matrix and buffalo using the strain Bifidobacterium animalis subsp. Lactis HN019 in order to identify the difference between the physico-chemical profile, viability of the probiotic strain used, and the presence of homologous immunomodulatory microRNAs in order to verify if the modifications suffered in the bovine and buffalo matrices during the fermentation process by probiotic bacteria would interfere with the presence of immunomodulatory miRNAs and the mucosal immune response. Conclusion: The results showed higher protein content, total solids and fat in the buffalo matrix in relation to the bovine matrix. While in the fermented buffalo matrix presented higher content of fatty acids compared to fermented bovine matrix, the profile of acidification and post acidification was similar in both matrices. The fermentation process in distinct milk matrices provided a modification of the immunological cell profile in the intestinal mucosa but led to the destruction of the miRNAs of the thermal processing, identifying that this modification of the immune response is independent of the homologous microRNAs studied.

A técnica de cultivo em camada delgada contendo ágar Middlebrook 7H11 modificado foi comparada com o cultivo padrão em meio de Stonebrink, visando avaliar a sensibilidade e o tempo de detecção de Mycobacterium bovis em órgãos de bovinos e bubalinos oriundos de abatedouros comerciais. Posteriormente, a PCR foi utilizada para a confirmação do crescimento observado nos cultivos, bem como a coloração de Ziehl-Neelsen na pesquisa de bacilos álcool-ácido resistentes. As 49 amostras testadas foram descontaminadas pelo método tradicional de Petroff e trabalhadas em duas etapas. Na primeira, todas foram semeadas nas placas contendo o meio de Middlebrook 7H11 em camada delgada e nos tubos contendo o meio de Stonebrink, e as colônias observadas macroscopicamente em ambos os meios foram submetidas à PCR. Na segunda, 10 amostras cultivadas na primeira etapa foram submetidas a novo cultivo, somente em camada delgada, para observação do crescimento microscópico das colônias e também analisadas pela PCR. Os resultados obtidos demonstraram que: 1) a técnica de cultivo de Mycobacterium bovis em camada delgada no meio de Middlebrook 7H11 modificado em amostras de órgãos de bovinos e bubalinos mostrou-se viável quando comparada ao cultivo clássico no meio de Stonebrink, reduzindo o tempo de isolamento e podendo ser utilizada de forma complementar aos métodos tradicionais de diagnóstico da tuberculose bovina; 2) foi possível a identificação precoce do crescimento das micobactérias em camada delgada (entre 12º e 25º dia de crescimento) quando comparadas ao Stonebrink; 3) a PCR mostrou-se uma ferramenta complementar à somatória das técnicas de descontaminação de Petroff, coloração de Ziehl-Neelsen e cultivo em camada delgada na confirmação do diagnóstico de presença de micobactérias em amostras de órgãos de bovinos e bubalinos. / The modified thin layer Middlebrook 7H11 cultivation was compared to the standard culture technique containing Stonebrink media, in order to evaluate the sensitivity and time for the detection of Mycobacterium bovis in bovine and buffalo organs deriving from commercial slaughterhouses. The PCR was applied for confirmation of the growth observed in the cultures, as well as the Ziehl-Neelsen color technique in order to detect acid-fast bacilli. 49 samples were submitted to the classic Petroff\'s decontamination method, and worked in two stages. In the first one, all of them were sowed in plates containing modified Middlebrook 7H11 agar in thin layer and in tubes containing the Stonebrink media, and the colonies observed macroscopically in both medias were submitted to the PCR. In the second stage, 10 samples from the first stage were submitted to a new culture, only in thin layer, for microscopical growth observation of the colonies and also submitted to the PCR. The results showed that: 1) Mycobacterium bovis cultivation in modified thin layer Middlebrook 7H11 for bovine and buffalo samples were viable when compared to the classic culture in Stonebrink, reducing the time of isolation, and can be applied as a complement to the traditional bovine tuberculosis diagnosis methods; 2) earlier identification of mycobacteria growth was found in thin layer (between 12nd and 25th day of growth) when compared to the Stonebrink; 3) PCR technique showed to be a complementary tool to the sum of techniques including Petroff decontamination, Ziehl-Neelsen color and thin layer cultivation for the diagnosis confirmation of the presence of mycobacteria in bovine and buffalo organs samples .

A técnica de cultivo em camada delgada contendo ágar Middlebrook 7H11 modificado foi comparada com o cultivo padrão em meio de Stonebrink, visando avaliar a sensibilidade e o tempo de detecção de Mycobacterium bovis em órgãos de bovinos e bubalinos oriundos de abatedouros comerciais. Posteriormente, a PCR foi utilizada para a confirmação do crescimento observado nos cultivos, bem como a coloração de Ziehl-Neelsen na pesquisa de bacilos álcool-ácido resistentes. As 49 amostras testadas foram descontaminadas pelo método tradicional de Petroff e trabalhadas em duas etapas. Na primeira, todas foram semeadas nas placas contendo o meio de Middlebrook 7H11 em camada delgada e nos tubos contendo o meio de Stonebrink, e as colônias observadas macroscopicamente em ambos os meios foram submetidas à PCR. Na segunda, 10 amostras cultivadas na primeira etapa foram submetidas a novo cultivo, somente em camada delgada, para observação do crescimento microscópico das colônias e também analisadas pela PCR. Os resultados obtidos demonstraram que: 1) a técnica de cultivo de Mycobacterium bovis em camada delgada no meio de Middlebrook 7H11 modificado em amostras de órgãos de bovinos e bubalinos mostrou-se viável quando comparada ao cultivo clássico no meio de Stonebrink, reduzindo o tempo de isolamento e podendo ser utilizada de forma complementar aos métodos tradicionais de diagnóstico da tuberculose bovina; 2) foi possível a identificação precoce do crescimento das micobactérias em camada delgada (entre 12º e 25º dia de crescimento) quando comparadas ao Stonebrink; 3) a PCR mostrou-se uma ferramenta complementar à somatória das técnicas de descontaminação de Petroff, coloração de Ziehl-Neelsen e cultivo em camada delgada na confirmação do diagnóstico de presença de micobactérias em amostras de órgãos de bovinos e bubalinos. / The modified thin layer Middlebrook 7H11 cultivation was compared to the standard culture technique containing Stonebrink media, in order to evaluate the sensitivity and time for the detection of Mycobacterium bovis in bovine and buffalo organs deriving from commercial slaughterhouses. The PCR was applied for confirmation of the growth observed in the cultures, as well as the Ziehl-Neelsen color technique in order to detect acid-fast bacilli. 49 samples were submitted to the classic Petroff\'s decontamination method, and worked in two stages. In the first one, all of them were sowed in plates containing modified Middlebrook 7H11 agar in thin layer and in tubes containing the Stonebrink media, and the colonies observed macroscopically in both medias were submitted to the PCR. In the second stage, 10 samples from the first stage were submitted to a new culture, only in thin layer, for microscopical growth observation of the colonies and also submitted to the PCR. The results showed that: 1) Mycobacterium bovis cultivation in modified thin layer Middlebrook 7H11 for bovine and buffalo samples were viable when compared to the classic culture in Stonebrink, reducing the time of isolation, and can be applied as a complement to the traditional bovine tuberculosis diagnosis methods; 2) earlier identification of mycobacteria growth was found in thin layer (between 12nd and 25th day of growth) when compared to the Stonebrink; 3) PCR technique showed to be a complementary tool to the sum of techniques including Petroff decontamination, Ziehl-Neelsen color and thin layer cultivation for the diagnosis confirmation of the presence of mycobacteria in bovine and buffalo organs samples .

Thesis (Ph. D.)--Ohio State University, 2006. / Available online via OhioLINK's ETD Center; full text release delayed at author's request until 2009 Jun 15