992 resultados para Tuberculosis in cattle.


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Atresia coli is a congenital defect with disruption of the intestinal flow. Its etiopathogenesis is still unknown and the prognosis is reserved. This paper describes the case of a one week old Holstein Friesian calf that was referred to the HCVC, and was diagnosed with atresia coli. This confirmation was made by contrast radiography and the lesion was detected in dorsal portion of the spiral colon. A cecostomy was performed followed by a marsupialization of the intestinal cecum to the abdominal wall. After 36 hours of surgery, calf’s state worsens dramatically and for reasons of welfare, it was proceeded to sacrifice. The post-operative recovery is possible, even though the mortality rate is high. As in this case, this mortality rate increases when early diagnosis of atresia coli does not take place and there is peritonitis.

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Thesis (Master's)--University of Washington, 2016-08

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Although diarrhoea caused by Cryptosporidium is prevalent in livestock species throughout the world relatively little is known about the species and subtypes of Cryptosporidium found in cattle on Scottish farms. In particular, little is known about the shedding profiles (age when calves become infected and duration of shedding) of the different species found in cattle and how calves become infected. There are several theories about how neonatal calves first become infected with the parasite but the role which adult cattle play in the transmission of the parasite has not been fully addressed. It was previously thought that adult cattle did not become infected with the same species of Cryptosporidium which causes disease in the young calves. Some studies have shown that this may not be true and with the advance of new techniques to discriminate species this is an area which should be revisited. In addition, it is known that it is possible for humans to become infected with Cryptosporidium and show clinical disease early in life and then again later in adulthood. In livestock however, diarrhoea caused by the parasite is generally only seen in neonatal livestock while older animals tend to be asymptomatic. It is not known if this resistance to clinical disease at an older age is due to changes in the host with an increase in age or if prior infection “immunises” the animal and provides protection against re-infection. It is also not known if infection with one isolate of C. parvum will provide protection against infection with another or if the protection formed is species/isolate specific. The main aims of this thesis were to: determine the species and subtypes of Cryptosporidium found in calves on a study farm over a one year period from birth; assess the role which adult cattle play in the transmission of the parasite to newborn calves; develop new typing tools to enable the rapid and easy differentiation of Cryptosporidium species found in cattle and to examine the host-pathogen interactions in animals given serial experimental challenges with distinct Cryptosporidium parvum isolates to determine if the resistance seen in older animals on farms is due to an increase in age or as a result of prior infection. iii A variety of different approaches were taken to achieve these aims. Longitudinal experiments carried out on a study farm revealed that in calves <9 weeks of age the most common species of Cryptosporidium is C. parvum and that all calves in the group became infected with Cryptosporidium within the first two weeks of life. Sample collection from the same animals later in life (at 6 months of age) showed that contrary to most previous studies the most common species detected at in this age group was also C. parvum although, interestingly, the subtype which the calves were shedding was not the same subtype that they were shedding previously. The longitudinal study which investigated the role of adult cattle in the transmission of Cryptosporidium also yielded some interesting results. It was found that most of the adult cattle on this farm were shedding Cryptosporidium albeit intermittently. Speciation of the positive samples revealed that, on this farm, the most predominant species of Cryptosporidium in adult cattle was also C. parvum. This is very unusual as most previous studies have not found this level of infection in older cattle and C. parvum is not usually found in this age group. A number of different subtypes were found in adult cattle and some animals shed more than one subtype over the course of the study. This contradicts prior findings which demonstrated that only one subtype is found on a single farm. The experimental infection trial involving infection of young (<1 week old) and older (6 week old) lambs with distinct C. parvum isolates demonstrated that an increase in age at primary infection reduces the effect of clinical disease. Animals which were infected at <1 week of age were re-challenged at 6 weeks of age with either a homologous or heterologous infection. Results revealed that previous exposure does not protect against re-infection with the same or a different isolate of C. parvum. This study also demonstrated that an increase in infective dose leads to a shorter pre-patent period and that there are variations in the clinical manifestations of different isolates of the same Cryptosporidium species.

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Leptospirosis is an important but neglected zoonotic disease that is often overlooked in Africa. Although comprehensive data on the incidence of human disease are lacking, robust evidence of infection has been demonstrated in people and animals from all regions of the continent. However, to date, there are few examples of direct epidemiological linkages between human disease and animal infection. In East Africa, awareness of the importance of human leptospirosis as a cause of non-malarial febrile illness is growing. In northern Tanzania, acute leptospirosis has been diagnosed in 9% of patients with severe febrile illness compared to only 2% with malaria. However, little is known about the relative importance of different potential animal hosts as sources of human infection in this area. This project was established to investigate the roles of rodents and ruminant livestock, important hosts of Leptospira in other settings, in the epidemiology of leptospirosis in northern Tanzania. A cross-sectional survey of rodents living in and around human settlements was performed alongside an abattoir survey of ruminant livestock. Unusual patterns of animal infection were detected by real-time PCR detection. Renal Leptospira infection was absent from rodents but was detected in cattle from several geographic areas. Infection was demonstrated for the first time in small ruminants sub-Saharan Africa. Two major Leptospira species and a novel Leptospira genotype were detected in livestock. L. borgpetersenii was seen only in cattle but L. kirschneri infection was detected in multiple livestock species (cattle, sheep and goats), suggesting that at least two distinct patterns of Leptospira infection occur in livestock in northern Tanzania. Analysis of samples from acute leptospirosis in febrile human patients could not detect Leptospira DNA by real-time PCR but identified social and behavioural factors that may limit the utility of acute-phase diagnostic tests in this community. Analysis of serological data revealed considerable overlap between serogroups detected in cattle and human leptospirosis cases. Human disease was most commonly attributed to the serogroups Mini and Australis, which were also predominant reactive serogroups in cattle. Collectively, the results of this study led to the hypothesis that livestock are an important reservoir of Leptospira infection for people in northern Tanzania. These results also challenge our understanding of the relationship between Leptospira and common invasive rodent species, which do not appear to maintain infection in this setting. Livestock Leptospira infection has substantial potential to affect the well-being of people in East Africa, through direct transmission of infection or through indirect effects on food production and economic security. Further research is needed to quantify the impact of livestock leptospirosis in Africa and to develop effective interventions for the control of human and animal disease.

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Background: Tuberculosis is one of the world’s most common causes of death in the era of Human immunodeficiency virus. The purpose of this study was to determine the prevalence and associated factors of TB/HIV co-infection. Methods: Hospital based retrospective studies were conducted among adult HIV-positive patients. Logistic regression method and Chi square test were applied. Results: A total of 571 HIV positive study participants were enrolled. Of these, 158 (27.7%) were found to have pulmonary tuberculosis. Lower baseline CD4 count<200cell/μl, patients who drunk alcohol, patients who were ambulatory at the initiation of ART, patients whose marital status was single were significant predictors for increased risk of tuberculosis in PLWHIV (P <0.05). Non smoker patients, patients in WHO clinical stage I, patients in WHO clinical stage II and ownership of the house had significant protective benefit against risk of TB (P <0.05). Conclusion: The prevalence of TB/HIV co-infection in adults on ART in our study was moderately high. Having advanced clinical status and presence of risk factors were found to be the predicting factors for co-infection. The health office should open TB/HIV co-infection units in the hospitals and health workers should be cautious when a patient has an advanced disease.

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Mycobacterium bovis causes animal tuberculosis (TB) in cattle, humans, and other mammalian species, including pigs. The goal of this study was to experimentally assess the responses of pigs with and without a history of tonsillectomy to oral vaccination with heat-inactivated M. bovis and challenge with a virulent M. bovis field strain, to compare pig and wild boar responses using the same vaccination model as previously used in the Eurasian wild boar (Sus scrofa), to evaluate the use of several enzyme-linked immunosorbent assays (ELISAs) and lateral flow tests for in vivo TB diagnosis in pigs, and to verify if these tests are influenced by oral vaccination with inactivated M. bovis. At necropsy, the lesion and culture scores were 20% to 43% higher in the controls than those in the vaccinated pigs. Massive M. bovis growth from thoracic tissue samples was observed in 4 out of 9 controls but in none of the 10 vaccinated pigs. No effect of the presence or absence of tonsils was observed on these scores, suggesting that tonsils are not involved in the protective response to this vaccine in pigs. The serum antibody levels increased significantly only after challenge. At necropsy, the estimated sensitivities of the ELISAs and dual path platform (DPP) assays ranged from 89% to 94%. In the oral mucosa, no differences in gene expression were observed in the control group between the pigs with and without tonsils. In the vaccinated group, the mRNA levels for chemokine (C-C motif) receptor 7 (CCR7), interferon beta (IFN-β), and methylmalonyl coenzyme A mutase (MUT) were higher in pigs with tonsils. Complement component 3 mRNA levels in peripheral blood mononuclear cells (PBMC) increased with vaccination and decreased after M. bovis challenge. This information is relevant for pig production in regions that are endemic for M. bovis and for TB vaccine research.

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Environmental factors may drive tick ecology and therefore tick-borne pathogen (TBP) epidemiology, which determines the risk to animals and humans of becoming infected by TBPs. For this reason, the aim of this study was to analyze the influence of environmental factors on the abundance of immature-stage Ixodes ricinus ticks and on the prevalence of two zoonotic I. ricinus-borne pathogens in natural foci of endemicity. I. ricinus abundance was measured at nine sites in the northern Iberian Peninsula by dragging the vegetation with a cotton flannelette, and ungulate abundance was measured by means of dung counts. In addition to ungulate abundance, data on variables related to spatial location, climate, and soil were gathered from the study sites. I. ricinus adults, nymphs, and larvae were collected from the vegetation, and a representative subsample of I. ricinus nymphs from each study site was analyzed by PCR for the detection of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum DNA. Mean prevalences of these pathogens were 4.0% ± 1.8% and 20.5% ± 3.7%, respectively. Statistical analyses confirmed the influence of spatial factors, climate, and ungulate abundance on I. ricinus larva abundance, while nymph abundance was related only to climate. Interestingly, cattle abundance rather than deer abundance was the main driver of B. burgdorferi sensu lato and A. phagocytophilum prevalence in I. ricinus nymphs in the study sites, where both domestic and wild ungulates coexist. The increasing abundance of cattle seems to increase the risk of other hosts becoming infected by A. phagocytophilum, while reducing the risk of being infected by B. burgdorferi sensu lato. Controlling ticks in cattle in areas where they coexist with wild ungulates would be more effective for TBP control than reducing ungulate abundance.

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Mycobacterium bovis is the etiological agent of tuberculosis in domestic and wild animals. Its involvement as a human pathogen has been highlighted again with the recent descriptions of transmission through dairy products (18), reactivation or primary infection in human immunodeficiency virus-infected patients (5), and association with meat industry workers, animal keepers, or hunters (3). Strains resistant to antituberculous drugs (M. bovis is naturally resistant to pyrazinamide) pose an additional risk (2). Several studies have demonstrated that mutations in target genes are associated with resistance to antituberculous drugs (4, 7, 10, 11, 16). However, most of them have been developed in Mycobacterium tuberculosis strains and limited data are available regarding M. bovis isolates. The aim of this study was to characterize by sequencing the main genes involved in antibiotic resistance in two multidrug-resistant (MDR) M. bovis isolates in a human outbreak detected in a hospital in Madrid that subsequently spread to several countries (5, 6, 15). The isolates were resistant to 11 drugs, but only their rpoB and katG genes have been analyzed so far (1, 14). We studied the first (93/R1) and last (95/R4) M. bovis isolates of this nosocomial outbreak, characterized by spoligotyping as SB0426 (hexacode 63-5F-5E-7F-FF-60 in the database at www.mbovis.org) (1, 13). Several genes involved in resistance to isoniazid (katG, ahpC, inhA, and the oxyR-ahpC intergenic region), rifampin (rpoB), streptomycin (rrs, rpsL), ethambutol (embB), and quinolones (gyrA) were studied. These genes, or fragments of genes, were amplified and sequenced as previously described (12). The sequence analysis revealed polymorphisms in five (ahpC, rpoB, rpsL, embB, and gyrA) out of nine analyzed genes (Table 1). Nucleotide substitutions in four genes cause a change in the encoded amino acid. Two additional synonymous mutations in ahpC and rpsL differentiated the first and last isolates from the outbreak.

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Foot-and-mouth disease (FMD), a disease of cloven hooved animals caused by FMD virus (FMDV), is one of the most economically devastating diseases of livestock worldwide. The global burden of disease is borne largely by livestock-keepers in areas of Africa and Asia where the disease is endemic and where many people rely on livestock for their livelihoods and food-security. Yet, there are many gaps in our knowledge of the drivers of FMDV circulation in these settings. In East Africa, FMD epidemiology is complicated by the circulation of multiple FMDV serotypes (distinct antigenic variants) and by the presence of large populations of susceptible wildlife and domestic livestock. The African buffalo (Syncerus caffer) is the only wildlife species with consistent evidence of high levels of FMDV infection, and East Africa contains the largest population of this species globally. To inform FMD control in this region, key questions relate to heterogeneities in FMD prevalence and impacts in different livestock management systems and to the role of wildlife as a potential source of FMDV for livestock. To develop FMD control strategies and make best use of vaccine control options, serotype-specific patterns of circulation need to be characterised. In this study, the impacts and epidemiology of FMD were investigated across a range of traditional livestock-keeping systems in northern Tanzania, including pastoralist, agro-pastoralist and rural smallholder systems. Data were generated through field studies and laboratory analyses between 2010 and 2015. The study involved analysis of existing household survey data and generated serological data from cross-sectional livestock and buffalo samples and longitudinal cattle samples. Serological analyses included non-structural protein ELISAs, serotype-specific solid-phase competitive ELISAs, with optimisation to detect East African FMDV variants, and virus neutralisation testing. Risk factors for FMDV infection and outbreaks were investigated through analysis of cross-sectional serological data in conjunction with a case-control outbreak analysis. A novel Bayesian modeling approach was developed to infer serotype-specific infection history from serological data, and combined with virus isolation data from FMD outbreaks to characterise temporal and spatial patterns of serotype-specific infection. A high seroprevalence of FMD was detected in both northern Tanzanian livestock (69%, [66.5 - 71.4%] in cattle and 48.5%, [45.7-51.3%] in small ruminants) and in buffalo (80.9%, [74.7-86.1%]). Four different serotypes of FMDV (A, O, SAT1 and SAT2) were isolated from livestock. Up to three outbreaks per year were reported by households and active surveillance highlighted up to four serial outbreaks in the same herds within three years. Agro-pastoral and pastoral livestock keepers reported more frequent FMD outbreaks compared to smallholders. Households in all three management systems reported that FMD outbreaks caused significant impacts on milk production and sales, and on animals’ draught power, hence on crop production, with implications for food security and livelihoods. Risk factor analyses showed that older livestock were more likely to be seropositive for FMD (Odds Ratio [OR] 1.4 [1.4-1.5] per extra year) and that cattle (OR 3.3 [2.7-4.0]) were more likely than sheep and goats to be seropositive. Livestock managed by agro-pastoralists (OR 8.1 [2.8-23.6]) or pastoralists (OR 7.1 [2.9-17.6]) were more likely to be seropositive compared to those managed by smallholders. Larger herds (OR: 1.02 [1.01-1.03] per extra bovine) and those that recently acquired new livestock (OR: 5.57 [1.01 – 30.91]) had increased odds of suffering an FMD outbreak. Measures of potential contact with buffalo or with other FMD susceptible wildlife did not increase the likelihood of FMD in livestock in either the cross-sectional serological analysis or case-control outbreak analysis. The Bayesian model was validated to correctly infer from ELISA data the most recent serotype to infect cattle. Consistent with the lack of risk factors related to wildlife contact, temporal and spatial patterns of exposure to specific FMDV serotypes were not tightly linked in cattle and buffalo. In cattle, four serial waves of different FMDV serotypes that swept through southern Kenyan and northern Tanzanian livestock populations over a four-year period dominated infection patterns. In contrast, only two serotypes (SAT1 and SAT2) dominated in buffalo populations. Key conclusions are that FMD has a substantial impact in traditional livestock systems in East Africa. Wildlife does not currently appear to act as an important source of FMDV for East African livestock, and control efforts in the region should initially focus on livestock management and vaccination strategies. A novel modeling approach greatly facilitated the interpretation of serological data and may be a potent epidemiological tool in the African setting. There was a clear temporal pattern of FMDV antigenic dominance across northern Tanzania and southern Kenya. Longer-term research to investigate whether serotype-specific FMDV sweeps are truly predictable, and to shed light on FMD post-infection immunity in animals exposed to serial FMD infections is warranted.

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Malignant Catarrhal Fever (MCF), an often-lethal infectious disease, presents as a variable complex of lesions in susceptible ungulate species. The disease is caused by a -herpesvirus following transmission from an inapparent carrier host. Two major epidemiological forms exist: wildebeest-associated MCF (WA-MCF), in which the virus is transmitted to susceptible species by wildebeest calves less than approximately four months of age, and sheepassociated MCF (SA-MCF) in which the virus is spread by sheep (primarily adolescents). Due to the lack of an in-vitro propagation system for the causative agent of the more economically significant SA-MCF, and with the expectation that cross-protective immunity may be provided, vaccine development has focused on the more easily propagated alcelaphine herpesvirus-1 (AlHV-1) that causes WA-MCF. In 2008 a direct viral challenge trial showed that a novel vaccine, employing an attenuated AlHV-1 (atAlHV-1) `C5000 virus strain, protected British Friesian-Holstein (FH) cattle against an intranasal challenge with virulent AlHV-1 `C5000 virus. For cattle keeping people living near wildebeest calving areas in sub-Saharan Africa an effective vaccine would have value as it would release them from the costly annual disease avoidance strategy of having to move their herds away from the oncoming wildebeest. On the other hand, an effective vaccine will release herd owners from the need to avoid MCF, allowing them to graze their cattle alongside wildebeest on the highly nutritious pastures of the calving areas. As such conservationists have raised concerns that the development of a vaccine might lead to detrimental grazing competition. The principle objective of this study was to test the novel vaccine on Tanzanian shorthorn zebu cross cattle (SZC).We did this firstly using a natural challenge field trial (Chapter Two) which demonstrated that immunisation with the atAlHV-1 vaccine was well tolerated and induced an oro-nasopharyngeal AlHV-1-specific and -neutralising antibody response. This resulted in an immunity in SZC cattle that was partially protective and reduced naturally transmitted infection by 56%. We also demonstrated that non-fatal infections occurred with a much higher frequency than previously thought. Because the calculated efficacy of the vaccine was less than that seen in British FH cattle we wanted to determine whether host factors, particular to SZC cattle, had impacted the outcomes of the field trial. To do this we repeated the 2008 direct viral challenge trial using SZC cattle (Chapter Four). During this trial we also investigated whether the recombinant bacterial flagellin monomer (FliC), when used as an adjuvant, might improve the vaccine’s efficacy. The findings from this trial indicated that direct challenge with pathogenic AlHV-1 is effective at inducing MCF in SZC cattle and that FliC is not an appropriate adjuvant for this vaccine. Furthermore, with less control group cattle dying of MCF than expected we speculate that SZC cattle may have a degree of resistance to MCF that affords them protection from infection and developing fatal disease. In Chapter Three we investigated aspects of the epidemiology of MCF, specifically whether wildebeest placenta, long implicated by Maasai cattle owners as a source of MCF, might play a role in viral transmission. Additionally, through comparative sequence analysis, at two specific genes (A9.5 and ORF50) of wild-type and atAlHV-1, we investigated whether the `C5000 strain, the source of which was taken from Africa more than 40 years ago, was appropriate for vaccine development. The detection of AlHV-1 virus in approximately 50% of placentae indicated that infection can occur in-utero and that this tissue might play a role in disease transmission. And, despite describing three new alleles of the A9.5 gene (supporting previous evidence that this gene is polymorphic and encodes a secretory protein with interleukin-4 as the major homologue), the observation that the most frequently detected haplotypes, in both wild-type and attenuated AlHV-1, were identical suggests that AlHV-1 has a slow molecular clock and that the attenuated strain was appropriate for vaccine development. In Chapter Five we present the first quantitative assessment of the annual MCF avoidance costs that Maasai pastoralists incur. In particular we estimated that as a result of MCF avoidance 64% of the total daily milk yield during the MCF season was not available to be used by the 81% of the family unit remaining at the permanent boma. This represents an upper-bound loss of approximately 8% of a household0s annual income. Despite these considerable losses we concluded that, given an incidence of fatal MCF in cattle living in wildebeest calving areas of 5% to 10%, if herd owners were to stop trying to avoid MCF by allowing their cattle to graze alongside wildebeest, any gains made through increased availability of milk, improved body condition and reduced energy demands would be offset by an increase in MCF-incidence. With the development of an effective vaccine, however, this alternative strategy might become optimal. The overall conclusion we draw therefore is that, despite the substantial costs incurred each year avoiding MCF, the partial protection afforded by the novel vaccine strategy is not sufficient to warrant a wholesale change in disease avoidance strategy. Nonetheless, even the partial protection provided by this vaccine could be of value to protect animals that cannot be moved, for example where some of the herd remain at the boma to provide milk or where land-use changes make traditional disease avoidance difficult. Furthermore, the vaccine may offer a feasible solution to some of the current land-use challenges and conflicts, providing a degree of protection to valuable livestock where avoidance strategies are not possible, but with less risk of precipitating the potentially damaging environmental consequences, such as overgrazing of highly nutritious seasonal pastures, that might result if herd owners decide they no longer need to avoid wildebeest.

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La tuberculosis TB es una de las principales causas de muerte en el mundo en individuos con infección por VIH. En Colombia esta coinfección soporta una carga importante en la población general convirtiéndose en un problema de salud pública. En estos pacientes las pruebas diagnósticas tienen sensibilidad inferior y la enfermedad evoluciona con mayor frecuencia hacia formas diseminadas y rápidamente progresivas y su diagnóstico oportuno representa un reto en Salud. El objetivo de este proyecto es evaluar el desempeño de las pruebas diagnósticas convencionales y moleculares, para la detección de TB latente y activa pacientes con VIH, en dos hospitales públicos de Bogotá. Para TB latente se evaluó la concordancia entre las pruebas QuantiFERON-TB (QTF) y Tuberculina (PPD), sugiriendo superioridad del QTF sobre la PPD. Se evaluaron tres pruebas diagnósticas por su sensibilidad y especificidad, baciloscopia (BK), GenoType®MTBDR plus (Genotype) y PCR IS6110 teniendo como estándar de oro el cultivo. Los resultados de sensibilidad (S) y especificidad (E) de cada prueba con una prevalencia del 19,4 % de TB pulmonar y extrapulmonar en los pacientes que participaron del estudio fue: BK S: 64% E: 99,1%; Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 73% E: 95,5%, de la misma forma se determinaron los valores predictivos positivos y negativos (VPP y VPN) BK: 88,9% y 94,8%, Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 90% y 95,7%. Se concluyó bajo análisis de curva ROC que las pruebas muestran un rendimiento diagnóstico similar por separado en el diagnóstico de TB en pacientes con VIH, aumentando su rendimiento diagnostico cuando se combinan

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RESUMO: A geleia de Wharton é uma fonte de células tronco mesenquimais (CTMs) que ainda não havia sido testada para a produção de embriões bovinos por transferência nuclear (TN). O objetivo deste estudo foi isolar, caracterizar e testar as CTMs derivadas da geleia de Wharton para produção de embriões e gestações por transferência nuclear em bovinos. O cordão umbilical foi coletado durante o nascimento e as células derivadas da geleia de Wharton (CGWs) foram isoladas por explante e cultivadas em Dulbecco?s Modified Eagle Medium. Fibroblastos (FB) da pele foram isolados após 6 meses de vida. As análises morfológicas foram realizadas pelas microscopias de campo claro e eletrônica de varredura durante o cultivo celular. Caracterização fenotípica e genotípica por citometria de fluxo, imunocitoquímica, RT-PCR e indução da diferenciação em linhagens celulares foi realizada com as CGWs. No procedimento de TN, ovócitos no estágio de metáfase II foram enucleados usando micromanipuladores, fusionados com CGWs ou FB e então ativados artificialmente. Micrografias de microscopia de varredura revelaram que CGWs tiveram forma variada sob cultivo. Os marcadores mesenquimais de CTMs (CD29+, CD73+, CD90+ and CD105+) foram expressos em cultura de CGWs bovina, como evidenciado por citometria de fluxo, imunocitoquímica e RT-PCR. Quando induzidas, estas células diferenciaram-se em osteócitos, condrócitos e adipócitos. Após classificação, as CGWs foram utilizadas na TN. A taxa de formação de blastocistos por TN com CGWs no sétimo dia de cultivo foi de 25,80±0,03%, similar a produção de blastócitos por TN com fibroblastos de pele (19,00±0,07). Gestações foram obtidas e mostraram que CGWs constituem um novo tipo celular para ser usado na clonagem animal. ABSTRACT: Wharton?s jelly is a source of mesenchymal stem cells (MSCs) that had not yet been tested for bovine embryo production by nuclear transfer (NT). Thus, the objective of this study was to isolate, characterize and test MSCs derived from Wharton?s jelly for embryo and pregnancy production by NT in cattle. The umbilical cord was collected during calving and cells derived from Wharton?s jelly (WJCs) were isolated by explant and cultured in Dulbecco?s Modified Eagle Medium. Skin Fibroblasts (FB) were isolated after 6 months of life. Morphological analysis was performed by bright field and scanning electron microscopy (SEM) during cell culture. Phenotypic and genotypic characterization by flow cytometry, immunocytochemistry, RT-PCR and differentiation induction in cell lineages were performed for WJC. In the NT procedure, oocytes at the arrested metaphase II stage were enucleated using micromanipulators, fused with WJCs or FB and later activated artificially. SEM micrographs revealed that WJCs have variable shape under culture. Mesenchymal markers of MSCs (CD29+, CD73+, CD90+ and CD105+) were expressed in bovine-derived WJC cultures, as evidenced by flow cytometry, immunocytochemistry and RT-PCR. When induced, these cells differentiated into osteocytes, chondrocytes and adipocytes. After classification, the WJCs were used in NT. Blastocyst formation rate by NT with WJCs at day 7 was 25.80±0.03%, similar to blatocyst rate with NT using skin fibroblasts (19.00±0.07%). Pregnancies were obtained and showed that WJCs constitute a new cell type for use in animal cloning.

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Growing need for infrastructure has led to expanding research on advances in road pavement materials. Finding solutions that are sustainable, environmentally friendly and cost-efficient is a priority. Focusing such efforts on low-traffic and rural roads can contribute with a significant progress in the vital circulatory system of transport for rural and agricultural areas. An important alternative material for pavement construction is recycled aggregates from solid wastes, including waste from civil engineering activities, mainly construction and demolition. A literature review on studies is made; it is performed a planned set of laboratory testing procedures aimed to fully characterize and assess the potential in-situ mechanical performance and chemical impact. Furthermore, monitoring the full-scale response of the selected materials in a real field construction site, including the production, laying and compaction operations. Moreover, a novel single-phase solution for the construction of semi-flexible paving layers to be used as alternative material to common concrete and bituminous layers is experimented and introduced, aiming the production and laying of a single-phase laid material instead of a traditional two phases grouted macadam. Finally, on a parallel research work for farming pavements, the possible use of common geotechnical anti-erosive products for the improvement of soil bearing capacity of paddock areas in cattle husbandries of bio-farms is evaluated. this thesis has clearly demonstrated the feasibility of using the sustainable recycled aggregates for low-traffic rural roads and the pavements of farming and agriculture areas. The pavement layers constructed with recycled aggregates provided satisfying performance under heavy traffic conditions in experimental pavements. This, together with the fact that these aggregates can be available in most areas and in large quantities, provides great impetus towards shifting from traditional materials to more sustainable alternatives. The chemical and environmental stability of these materials proves their soundness to be utilized in farming environments.

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The objective of the present Ph.D. thesis was to investigate with a One Health approach the epidemiological patterns of T. gondii infection in Italy, to better understand the transmission dynamics of the parasite, following different research lines. The results of a retrospective analysis in animals and human showed the widespread distribution of T. gondii in the study area, with specific antibodies found in various animal species and human populations, indicating its constant presence across diverse environments. The environment plays a significant role in T. gondii's epidemiology. Migratory aquatic birds, rodents, wolves, and wild boars were investigated as sentinels of their spread, highlighting the potential transmission across geographic areas and infection risks for wildlife in natural settings. The study also provided insights into seroprevalence in wolves. Dogs, subjected to serological investigations exhibited risk factors for T. gondii infection, such as cohabitation with cats, coprophagy behaviours, and continuous outdoor. Correlation between serological evidence of exposure to T. gondii and pathological anxiety in large-size dogs was observed, and the consumption of raw meat was associated with a higher risk of infection in these animals. Results of the investigations conducted in this thesis, demonstrate the dynamic nature of T. gondii infection in cattle, characterized by new infections and declining antibody levels over the production cycle. The study also describes a co-infection between T. gondii and Sarcocystis hominis in bovine eosinophilic myositis. In the final part of the Thesis, a comprehensive genotyping of T. gondii in Italy reveals the predominance of Type II strains, particularly in cases of ovine abortion and fatal toxoplasmosis among captive Lemur catta. This approach enhances our understanding of the parasite's genetic diversity and transmission patterns, vital for effective management of its impact on human and animal health in Italy.

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O período inicial da gestação de bovinos é caracterizado por grandes perdas embrionárias. Considerando a importância deste fator no âmbito da reprodução animal foram estudados os anexos embrionários e fetais bovinos fecundados por monta natural de 15-70 dias de gestação, com o objetivo de estabelecer parâmetros morfométricos da placenta na fase inicial da gestação. Com uso de um paquímetro foram realizadas mensurações do comprimento (crânio caudal), largura (latero lateral) e altura (dorso ventral) das membranas corioalantóide e amniótica. O início da formação dos cotilédones foi observado e quantificado, assim como, o peso placentário. O peso médio do saco gestacional aumentou com o evoluir da idade gestacional, entretanto, o crescimento foi acelerado a partir de 20-30 dias de gestação. O comprimento crânio caudal e dorso ventral da membrana corioalantóide e do âmnio apresentaram crescimento lento e gradual com o evoluir dos períodos gestacionais analisados. Com 30-40 dias de gestação, os primeiro cotilédones já eram visualizados e contatos com facilidade na superfície coriônica. Os períodos de crescimento coincidiram com os maiores índices de perdas gestacionais em bovinos. Os parâmetros aqui analisados poderão servir para futuras investigações dos anexos embrionários de organismos manipulados em laboratório.