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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.
11

Aspetti fisiopatologici della prostata di cane

Raccagni, Ramona <1983> 12 May 2011 (has links)
Il lavoro eseguito comprende 3 differenti studi inerenti l’approfondimento di diversi aspetti della fisiopatologia della prostata, in particolare l’aspetto clinico, biochimico ed ormonale. Per quanto riguarda l’aspetto clinico è stato eseguito uno studio ecografico sull’accrescimento e sviluppo della ghiandola, a partire dai 4 giorni di vita all’anno di età del cane. L’aspetto biochimico dell’organo è stato indagato nel secondo studio, analizzando l’eventuali differenze nel profilo proteico e nel profilo dello zinco, valutato con spettrofotometria ad assorbimento atomico, su campioni di plasma seminale di cani sani o cani affetti da iperplasia prostatica benigna sintomatica od asintomatica. Lo studio è stato eseguito allo scopo di valutare se l’approccio biochimico ai problemi prostatici possa essere d’aiuto nella diagnosi della più comune patologia della prostata, l’iperplasia prostatica benigna. Il terzo studio inerente l’aspetto ormonale della prostata, completa lo studio precedente, analizzando le eventuali differenze ormonali (Testosterone, Estrogeni e Progesterone) riscontrabili fra due gruppi di cani: i cani sani e quelli affetti da iperplasia prostatica benigna.
12

Equine and human mutual welfare: a whole subject? Critical aspects and possible strategies in equine-assisted activities and therapies

Li Destri Nicosia, Dora <1974> 12 May 2011 (has links)
General aim of the study is equine welfare, particularly concerning different husbandry methodic and inter-specific relational factors. Specific aim is the evaluation of possible mutual (to humans and to equines) benefits and the analysis of critical factors/strength points, of human-horse relationship within Therapeutic Riding context (TR). The peculiarities of human-horse relationship (compared to the bond with “Pet”) are analyzed, concerning their socio-anthropological, psychological, psycho-dynamic distinctive characteristics. 8 European representative therapeutic riding centers (TRC) were therefore selected (on the basis of their different animals’ husbandry criteria, and of the different rehabilitative methodologies adopted). TRC were investigated through 2 different questionnaires, specifically settled to access objective/subjective animal welfare parameters; the quality of human-horse relationship; technicians’ emotional experienced. 3 Centers were further selected, and behavioral (145 hours of behavioral recording) and physiological parameters (heart rate and heart rate variability) were evaluated, aimed to access equine welfare and horses’ adaptive responses/coping (towards general environment and towards TR job). Moreover a specific “handling-task” was ideated and experimented, aimed to measure the quality of TR technicians-horses relationship. We did therefore evaluate both the individual horses’ responses and the possible differences among Centers. Data collected highlight the lack of univocal standardized methodic, concerning the general animals’ management and the specific methodologies (aimed to improve animal welfare and to empower TR efficacy). Some positive and some critical aspects were detected concerning TR personnel-horse relationship. Another experimental approach did evaluate the efficacy (concerning the mutual benefits’ empowerment) of an “ethologically-fitted” TR intervention, aimed to educate children to and through the relationship with horses. Our data evidenced that the improvement of human horse relationship, through structured educational programs for TR personnel might have important consequences both to human and equine welfare.
13

Conservazione del seme sortato di suino / Storage of boar sexed semen

Vallorani, Claudia <1983> 24 May 2012 (has links)
Gli spermatozoi di suino sottoposti alla procedura di sessaggio mediante citofluorimetria presentano una serie di modificazioni morfo-funzionali che compromettono nel tempo la loro sopravvivenza e la capacità fecondante. Questi spermatozoi, inoltre, a causa della sensibilità ai danni indotti dalla crioconservazione, vengono solitamente conservati allo stato liquido a 15-17°C, con conseguente ulteriore peggioramento nel tempo della qualità delle cellule spermatiche sessate. Lo scopo della ricerca è stato quello di valutare le modificazioni di alcune caratteristiche morfo-funzionali degli spermatozoi in seguito a sex-sorting e conseguente conservazione. Successivamente si è cercato di migliorare i parametri qualitativi del seme sessato mediante l’aggiunta di sostanze antiossidanti e la messa a punto di una nuova metodica di conservazione. I risultati ottenuti hanno evidenziato che la procedura di sessaggio e la conseguente conservazione per 24-26 ore a 15°C hanno indotto un peggioramento significativo delle caratteristiche morfo-funzionali (vitalità, integrità acrosomiale, quantità e distribuzione dell’Hsp70, capacità fecondante). Mentre l’azione degli antiossidanti non si è rivelata efficace nel miglioramento della qualità degli spermatozoi durante le fasi di colorazione e passaggio attraverso il citofluorimetro, l’azione congiunta del plasma seminale e degli antiossidanti superossido-dismutasi ed epigallocatechina-3-gallato ha indotto un miglioramento significativo della vitalità degli spermatozoi. Per la conservazione del seme di suino è stata testata la tecnica di incapsulazione in membrane di alginato di bario che permette, durante l’inseminazione artificiale, un rilascio graduale degli spermatozoi e l’utilizzo di un quantitativo inferiore di materiale seminale. L’applicazione di tale tecnica per la conservazione degli spermatozoi di suino sessati non sembra provocare un calo significativo della vitalità, dell’integrità acrosomiale e dell’efficienza totale di fecondazione rispetto al seme sortato e conservato diluito suggerendo futuri studi in vivo. Una migliore conoscenza dei danni indotti da queste tecnologie e la loro minimizzazione potrà stimolare in futuro l’utilizzo su vasta scala del seme sessato nel suino. / Boar spermatozoa submitted to the sorting procedure show several morpho-functional modifications effective in compromising their survival and fertilization ability. Moreover ,boar spermatozoa, because of their susceptibility to damages induced by cryopreservation, are usually stored at 15-17°C after the sorting procedure; however, also the conservation at liquid state implies the worsening of semen quality. The aims of this research were: 1) to evaluate morpho-functional characteristics of sperm cells submitted to sex-sorting and consequent storage; 2) to try to improve the quality of sorted semen by the addition of antioxidants; 2) to set up a new storage method. Our results evidence a decreased quality of boar sorted-stored spermatozoa in term of: viability, acrosome integrity, amount and localization of Hsp70, fertilizing ability. During the staining step and the passage through the cytofluorimeter, antioxidants were not effective in improving sperm cells morpho-functional characteristics, while the addition of superoxide dismutase or epigallocatechin-3-gallate associated with seminal plasma induced an increase of viability of sorted boar spermatozoa stored 24 h at 15°C. Some researchers have utilized encapsulation in barium alginate membrane to store boar sperm cells. This technique allows a constant release of spermatozoa in sow reproductive system, avoiding the double/triple intervention of insemination and reducing the number of spermatozoa/insemination. The application of this technique in order to store boar sperm cells after sorting did not induce any impairment of sperm morpho-functional characteristics (viability, acrosome integrity, total efficiency of insemination) compared to sorted spermatozoa stored at liquid state, thus demonstrating the possibility to use this method to improve the reproductive performance of boar sorted semen.
14

Genetic Manipulation, Gene Silencing and Biomarker Development in Multiple Experimental Models.

De Cecco, Marco <1984> 27 January 2012 (has links)
The thesis is set in three different parts, according to the relative experimental models. First, the domestic pig (Sus scrofa) is part of the study on reproductive biotechnologies: the transgenesis technique of Sperm Mediated Gene Transfer is widely studied starting from the quality of the semen, through the study of multiple uptakes of exogenous DNA and lastly used in the production of multi-transgenic blastocysts. Finally we managed to couple the transgenesis pipeline with sperm sorting and therefore produced transgenic embryos of predetermined sex. In the second part of the thesis the attention is on the fruit fly (Drosophila melanogaster) and on its derived cell line: the S2 cells. The in vitro and in vivo models are used to develop and validate an efficient way to knock down the myc gene. First an efficient in vitro protocol is described, than we demonstrate how the decrease in myc transcript remarkably affects the ribosome biogenesis through the study of Polysome gradients, rRNA content and qPCR. In vivo we identified two optimal drivers for the conditional silencing of myc, once the flies are fed with RU486: the first one is throughout the whole body (Tubulin), while the second is a head fat body driver (S32). With these results we present a very efficient model to study the role of myc in multiple aspects of translation. In the third and last part, the focus is on human derived lung fibroblasts (hLF-1), mouse tail fibroblasts and mouse tissues. We developed an efficient assay to quantify the total protein content of the nucleus on a single cell level via fluorescence. We coupled the protocol with classical immunofluorescence so to have at the same time general and particular information, demonstrating that during senescence nuclear proteins increase by 1.8 fold either in human cells, mouse cells and mouse tissues.
15

Validation of a new method to assess the long-term Hypothalamic-Pituitary-Adrenal Activity using hair glucocorticoids as biomarkers. - Studies on pigs and laboratory Sprague-Dawley Rats

Scorrano, Fabrizio <1985> 11 June 2014 (has links)
The evaluation of chronic activity of the hypothalamic-pituitary-adrenal (HPA) axis is critical for determining the impact of chronic stressful situations. The potential use of hair glucocorticoids as a non-invasive, retrospective, biomarker of long term HPA activity is of great interest, and it is gaining acceptance in humans and animals. However, there are still no studies in literature examining hair cortisol concentration in pigs and corticosterone concentration in laboratory rodents. Therefore, we developed and validated, for the first time, a method for measuring hair glucocorticoids concentration in commercial sows and in Sprague-Dawley rats. Our preliminary data demonstrated: 1) a validated and specific washing protocol and extraction assay method with a good sensitivity in both species; 2) the effect of the reproductive phase, housing conditions and seasonality on hair cortisol concentration in sows; 3) similar hair corticosterone concentration in male and female rats; 4) elevated hair corticosterone concentration in response to chronic stress manipulations and chronic ACTH administration, demonstrating that hair provides a good direct index of HPA activity over long periods than other indirect parameters, such adrenal or thymus weight. From these results we believe that this new non-invasive tool needs to be applied to better characterize the overall impact in livestock animals and in laboratory rodents of chronic stressful situations that negatively affect animals welfare. Nevertheless, further studies are needed to improve this methodology and maybe to develop animal models for chronic stress of high interest and translational value in human medicine.
16

Studio di alcuni tratti del temperamento nel cane / Study on temperament traits in the Domestic Dog (Canis Familiaris)

Beghelli, Valentina <1982> 11 June 2014 (has links)
Il temperamento può essere definito come l’attitudine che un cane esprime verso le persone e verso altri animali, la combinazione di tratti fisici e mentali, acquisiti e non, che determinano il comportamento del cane. Tale parametro delinea perciò il carattere di un individuo, inclinazioni e tendenze, eccitabilità, tristezza, rabbia e il modo caratteristico di comportarsi di un individuo, con particolare riferimento alle interazioni sociali. La presente tesi di Dottorato rappresenta uno studio su alcuni tratti del temperamento nel cane domestico elaborato in 3 progetti sperimentali. Nei primi due progetti sono state analizzate le differenze attitudinali tra alcune razze canine attraverso l’applicazione di un test di temperamento in cuccioli di 60 giorni e in cani adulti, per valutare e confrontarne il temperamento, la socialità ed identificare profili tipici di razza. Nel terzo progetto un campione di cani morsicatori di canile e di proprietà è stato confrontato con due rispettivi gruppi di controllo. Analizzando i risultati è stato possibile mettere in evidenza caratteristiche di razza omogenee nell’interazione con stimoli inanimati, nelle interazioni sociali e in relazione alla possessività e sono stati delineati profili di razza sia nei cuccioli sia negli adulti. Si sono tuttavia, osservate variabilità individuali, intra-razza e intra-cucciolata, a testimonianza dell’influenza complessa e multifattoriale delle componenti genetica e ambientale sul comportamento dei cani. Il confronto tra cani morsicatori di canile e di proprietà ha messo in luce interessanti differenze tra i soggetti in termini di reattività, socievolezza, propensione all’interazione con il proprietario o con un estraneo, comportamenti di evitamento e velocità di reazione agli stimoli presentati. Il test applicato è risultato un valido strumento per valutare il temperamento di cani dichiarati aggressivi che sono stati sottoposti a situazioni nuove e a stimoli sconosciuti per poter ottenere una migliore visione d’insieme del temperamento del soggetto. / Temperament has been defined as the attitude expressed by the dog toward people or other animals, the combination of physical and mental traits, acquired or not, which determine the behavior of the dog and therefore delineates the character of an individual, his inclinations, trends and the characteristic way of behaving, with particular reference to social interactions. This work represents a study of temperamental traits in the Domestic Dog, developed in 3 experimental projects. In the first two projects the attitudinal differences between some dog breeds are analyzed, through the application of a temperament test in puppies 60 days old and adult, in order to evaluate and compare their temperament and sociability and to identify specific breed profiles. In the third project, a sample of biters dogs coming from different kennel of and pet biters dogs were tested and compared with two respective control groups. Analyzing the results, it was possible to highlight consistent breed characteristics in the interaction with inanimate stimuli, in social interactions and in relation to possessivness and a first breed profile has been outlined for both puppies and adults. However, individual variabilities were observed, relative to breed and litter, reflecting the complex and multifactorial influence of genetic and environmental components on the behavior of the dog. Furthermore, the study allowed us to evaluate dogs biters and compare them with the control groups, on the base of temperament traits. The comparison between biters coming from kennels and pet ones underlined differences in terms of reactivity, sociability, attitude to interact with the owner or with a stranger, in avoiding trends and velocity of reaction to the stimuli presented . The temperament test can be considered a valid tool to assess the temperament of aggressive dogs, in order to get a better overview of the temperament of the subjects.
17

Hair: a tool to evaluate the HPA axis activity

Peric, Tanja <1982> 11 June 2014 (has links)
Hair cortisol is a novel marker to measure long-term secretion cortisol free from many methodological caveats associated with other matrices such as plasma, saliva, urine, milk and faeces. For decades hair analysis has been successfully used in forensic science and toxicology to evaluate the exposure to exogenous substances and assess endogenous steroid hormones. Evaluation of cortisol in hair matrix began about a decade ago and have over the past five years had a remarkable development by advancing knowledge and affirming this method as a new and efficient way to study the hypothalamic-pituitary-adrenal (HPA) axis activity over a long time period. In farm animals, certain environmental or management conditions can potentially activate the HPA axis. Given the importance of cortisol in monitoring the HPA axis activity, a first approach has involved the study on the distribution of hair cortisol concentrations (HCC) in healthy dairy cows showing a physiological range of variation of this hormone. Moreover, HCC have been significantly influenced also by changes in environmental conditions and a significant positive correlation was detected between HCC and cows clinically or physiologically compromised suggesting that these cows were subjected to repeated HPA axis activation. Additionally, Crossbreed F1 heifers showed significantly lower HCC compared to pure animals and a breed influence has been seen also on the HPA axis activity stimulated by an environmental change showing thus a higher level of resilience and a better adaptability to the environment of certain genotypes. Hair proved to be an excellent matrix also in the study of the activation of the HPA axis during the perinatal period. The use of hair analysis in research holds great promise to significantly enhance current understanding on the role of HPA axis over a long period of time.
18

Hormonal parameters in foal hair: from birth to post weaning

Montillo, Marta <1986> 11 June 2014 (has links)
The aim of this study was to investigate cortisol and progesterone (P4) trends in hair from birth up to postweaning in Italian trotter foals. Hair sampling is non-invasive and hair concentrations provide retrospective information of integrated hormone secretion over periods of several months. Samples were collected at birth and at a distance of 30 days, collecting only regrowth hair, up to post weaning. From birth to 3 months, foals cortisol falls from 47.64±5.6 to 4.9±0.68 pg/mg (mean±standard error), due to the interruption of foetal-placental connection and progressive adaptation to extrauterine life. From the third month of life to post weaning concentrations don’t vary significantly, underlining a non-chronic activation of the HPA axis. Hair P4 significantly decreases in the first two samples (from 469.68±72,54 to 184.65±35.42 pg/mg). At 2 (111.78±37.13 pg/mg) and 3 months (35.96±6.33 pg/mg) hair concentrations don’t show significant differences. These concentrations are not due to interactions of the utero-placental tissues with foals, animals are still prepuberal and P4 isn’t produced by adrenals as a result of high stress. We could therefore hypothesize that the source of foal hair P4 could be milk, suckled from mares. The high individual variability in hair at 2 and 3 months is due to a gradual and subjective change in foal diet, from milk to solid food, and to the fact that mares do not allow to suckle. From fourth month to post weaning P4 concentration in hair remains around 37.56±6.45 pg/mg. In conclusion, hair collected at birth, giving information about last period of gestation, could be used along with traditional matrices, to evaluate foals maturity. Hair cortisol could give indications about foals capacity to adapt to extra-uterine life. Finally milk, configuring as a bringer of nutrients and energy and assuming the characteristic of a nutraceutical, could give fundamental information about parental care.
19

Studio longitudinale sulle capacità cognitive del cane: discriminazione di quantità ed apprendimento per imitazione in relazione all'attaccamento / Study on cognitive abilities in the dog: discrimination of quantities and imitation learning related to the attachment

Mattioli, Michela <1975> 11 June 2014 (has links)
Il presente studio ha indagato e valutato alcune abilità cognitive del cane: la capacità di discriminare quantità e le capacità di apprendimento mediante imitazione; quest’ultima è poi stata messa in relazione con l’attaccamento nei confronti del proprietario. Per l’esecuzione della prima indagine sono stati messi appunto due test: il primo si è basato esclusivamente sulla presentazione di uno stimolo visivo: diversi quantitativi di cibo, differenti tra loro del 50%, sono stati presentati al cane; la scelta effettuata dai soggetti testati è stata premiata con differenti tipi di rinforzo differenziale o non differenziale. Il secondo test è stato diviso in due parti: sono stati presentati al cane diversi quantitativi di cibo sempre differenti tra loro del 50% ma nella prima parte del test l’input sensoriale per il cane è stato esclusivamente uditivo mentre nella seconda parte è stato sia uditivo che visivo. Ove è stato possibile è stato applicato ai cani un cardiofrequenzimetro al fine di eseguire una valutazione delle variazioni della frequenza cardiaca nel corso del test. Lo scopo è stato quello di valutare se i soggetti testati erano in grado di discriminare la quantità maggiore. La seconda indagine ha analizzato le capacità di apprendimento di 36 soggetti che sono stati suddivisi in cani da lavoro e pet. I soggetti protagonisti dello studio hanno eseguito il Mirror Test per la valutazione dell’apprendimento per imitazione. I soggetti presi in considerazione, sono stati sottoposti a scansione termografica all’inizio ed al termine del test ed è stata rilevata la loro frequenza respiratoria nella fase iniziale e finale del test. In 11 soggetti che hanno eseguito il precedente test è stato possibile eseguire anche il Strange Situation Test per la valutazione dell’attaccamento al proprietario; i test in questione sono stati videoregistrati ed analizzati per mezzo di un software preposto (OBSERVER XT 10). / The present study investigated and evaluated some cognitive abilities of the dog: the ability to discriminate quantity and to learn through imitation; the latter kind of learning was related to the dog’s attachment to the owner. In the first analysis two tests were applied: the first is based on the presentation of a visual stimulus: different amounts of food, different from each other by 50% , were presented to the dog; the choice of the dogs was rewarded with different types of differential or non-differential reinforcement. The second test was divided into two parts: different quantities of food (different from each other by 50 %) were submitted to the dogs; in the first part of the test, the sensory input was exclusively auditory, while in the second part both auditory and visual. Where feasible, a heart rate monitor was applied to the dogs, in order to perform an assessment of the heart rate changes during the test. The aim of the test was to evaluate if the subjects were able to discriminate the larger amount of food. The second study analyzed the learning ability of 36 subjects, divided into working dogs and pets. The subjects performed the Mirror Test for the assessment of learning by imitation. In addition the subjects were subjected to thermal scanning at the beginning and at the end of the test and their respiratory rate was detected before and after the test. Finally, in 11 of these subjects the Strange Situation Test for the assessment of attachment to the owner, was performed. All tests were videotaped and then analyzed using a dedicated software (OBSERVER XT 10).
20

Il cane come modello animale spontaneo di patologie neoplastiche dell'uomo: ene Ataxia-Telangiectasia Mutated (ATM) Nnella predisposizione al cancro ed importanza dei riarrangimanti genici dei geni Ig/TCR per la diagnosi e prognosi delle malattie linfoproliferative

Gentilini, Fabio <1971> 05 May 2009 (has links)
“Naturally occurring cancers in pet dogs and humans share many features, including histological appearance, tumour genetics, molecular targets, biological behaviour and response to conventional therapies. Studying dogs with cancer is likely to provide a valuable perspective that is distinct from that generated by the study of human or rodent cancers alone. The value of this opportunity has been increasingly recognized in the field of cancer research for the identification of cancer-associated genes, the study of environmental risk factors, understanding tumour biology and progression, and, perhaps most importantly, the evaluation and development of novel cancer therapeutics”.(Paoloni and Khanna, 2008) In last years, the author has investigated some molecular features of cancer in dogs. The Thesis is articulated in two main sections. In section 1, the preliminary results of a research project aimed at investigating the role of somatic mutations of Ataxia-Telangiectasia mutated (ATM) gene in predisposing to cancer in boxer dogs, are presented. The canine boxer breed may be considered an unique opportunity to disclose the role of ATM somatic mutation since boxer dogs are known to be dramatically susceptible to cancer and since they may be considered a closed gene pool. Furthermore, dogs share with human the some environment. Overall, the abovementioned features could be considered extremely useful for our purposes. In the section 2, the results of our studies aimed at setting up accurate and sensitive molecular assays for diagnosing and assessing minimal residual disease in lymphoproliferative disorders of dogs, are presented. The results of those molecular assay may be directly translated in the field of Veterinary practice as well as the may be used to improve our objective evaluation of new investigational drugs effectiveness in canine cancer trials.

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