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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

Obtenção de plasma rico em plaquetas autólogo de coelhos com poucos leucócitos e hemácias / Obtaining of autologous platelet-rich plasma of rabbits with few leukocytes and erythrocytes

Andrade, Marina Greco Magalhães Guerra de 14 August 2014 (has links)
The objective was to develop a method to obtain an autologous rich plasma in platelets with few leukocytes and blood cells using the whole blood of rabbits submitted to two centrifugations. Blood was collected by intracardiac route 10.5mL and distributed into three tubes of blood sedimentation containing sodium citrate. The tubes with blood was submitted to centrifugation at 2,000 rpm (670,8G) for 20 minutes and the sedimentation columns were aspirated from each tube 1.000μL of plasma to reduce the volume of supernatant. It was aspirated the plasma above the ring of leukocytes and transferred it to another tube to centrifugate again at 2000 rpm (670.8 L) for 10 minutes. The platelet content in the bottom of the tube was resuspended and homogenized 1.000μL the supernatant plasma to form the PRP liquid (Group G1). The capacity of platelet activation was observed from the formation of a clot called PRP gel (group G2) when it was added 100mL of rabbit thromboplastin, calcium chloride 0.0125 mol /l and sodium chloride 0.1 mol / l of PRP 100mL liquid. The counting of the platelets, erythrocytes and leukocytes total number was done before and after centrifugations and they were performed in a veterinary automatic hematology analyzer. It was noted in G1, an increase of 61.58% in relation to platelet blood count to get the average concentration of 370 484 platelets / uL in PRP and were eliminated from the process 71% to 89% of leukocytes and erythrocytes. The evaluation by transmission electron microscopy identified in G1 that platelets showed morphological integrity preserved and individualized, with intact cell membrane, emission of pseudopods and centralization of granules and organelles. In G2, the platelets were grouped, with difficult to identify the intracytoplasmic structures of cell, membrane lysis, shedding of cytoplasmic granules into the extracellular place and the presence of fibrin. The method for obtaining an autologous plasma rich of platelets in rabbits is simple and reduce the number of leukocytes and blood cells and the platelets continue with a morphological and functional integrity. / Objetivou-se elaborar um método de obtenção de plasma rico em plaquetas (PRP) autólogo com poucos leucócitos e hemácias a partir do sangue total de coelhos submetido a duas centrifugações. Foram colhidos 10,5mL sangue por via intracardíaca e distribuido em três tubos de hemossedimentação contendo citrato de sódio. Os tubos contendo as amostras foram submetidos a uma centrifugação à 2.000 RPM (670,8G) por 20 minutos e da coluna de sedimentação foram aspirados de cada tubo1.000μL de plasma para a redução do volume sobrenadante. Aspirou-se o plasma acima do anel de leucócitos e transferiu-se para outro tubo para centrifugação a 2.000 RPM por 10 minutos. O conteúdo plaquetário no fundo do tubo foi ressuspendido e homogeneizado à 1.000μL do plasma sobrenadante para formar o PRP líquido (Grupo G1). A capacidade de ativação das plaquetas foi verificada a partir da formação do PRP gel (Grupo G2), quando foram adicionados 100μL de tromboplastina com cloreto de cálcio 0,0125mol/l e cloreto de sódio 0,1mol/l, à 100μL de PRP líquido. A contagem do número total de plaquetas, hemácias e leucócitos antes e após as centrifugações foi realizada em analisador hematológico automático. Notou-se no G1, acréscimo de 61,58% de plaquetas em relação à média do hemograma ao obter a concentração de 370.484 plaquetas/μL no PRP e foram eliminados do processo 71% de leucócitos e 89% de hemácias. A avaliação por microscopia eletrônica de transmissão identificou no grupo G1 que as plaquetas se apresentavam com integridade morfológica preservada e se mostravam individualizadas, com membrana celular íntegra, emissão de pseudópodes e centralização dos grânulos e organelas. No G2, as plaquetas se encontravam agrupadas, de difícil identificação das estruturas intracitoplasmáticas, lise de membrana celular, derramamento de grânulos citoplasmáticos no meio extracelular e presença de fibrina. O método de obtenção de plasma rico em plaqueta autólogo de coelhos é simples, reduz o número de leucócitos e hemácias e preserva a integridade morfologica e funcional das plaquetas. / Mestre em Ciências Veterinárias
12

Rearing programmes for breeding rabbits. Effect of early development and feeding on future reproductive performance of rabbit females and males

Martínez Paredes, Eugenio Melchor 02 September 2019 (has links)
[ES] Cualquier mejora en el conocimiento de la nutrición y el manejo de los futuros conejos reproductores debe considerarse como prioritario en la producción cunícola. Sin embargo, los principales esfuerzos en investigación se han centrado en estos animales durante la fase de reproducción propiamente dicha. La hipótesis inicial de esta tesis fue que alcanzar un desarrollo temprano adecuado durante la gestación, lactancia, engorde y recría, con la ayuda de programas ajustados de alimentación en algunos de estos períodos, mejoraría el rendimiento reproductivo y la vida útil de los futuros conejos reproductores. Para evaluar esta hipótesis, se llevaron a cabo dos tipos de ensayos, tanto en conejos hembra de líneas maternas como en machos de líneas seleccionadas por velocidad de crecimiento y destinadas a la inseminación artificial. El primero de estos ensayos se centró en los diferentes patrones de crecimiento, desde el nacimiento hasta el final de la fase de recría, y su influencia en la carrera reproductiva y la vida útil del conejo. En el segundo tipo de pruebas, se evaluó el efecto del uso de diferentes dietas o programas de alimentación durante el período de recría en la productividad a corto y medio plazo. Los resultados muestran dos fases importantes en el desarrollo temprano, de acuerdo con sus efectos sobre el rendimiento reproductivo y la vida útil. Mostrar un mayor desarrollo corporal desde el nacimiento hasta los 63 días de vida parece tener una influencia positiva en el grado de madurez y la productividad al comienzo de su vida reproductiva, además de poder mejorar su supervivencia a corto plazo, pero con posibles efectos negativos en la esperanza de vida a largo plazo. Sin embargo, el desarrollo durante el período de recría (desde los 63 días de vida hasta el comienzo de la carrera reproductiva) parece tener un mayor impacto en la productividad y la esperanza de vida de nuestros futuros conejos reproductores. Las hembras más engrasadas en la primera inseminación tuvieron tamaños de camada más pequeños y un mayor riesgo de ser sacrificadas que las magras (P<0.05). Además, los machos que mostraron una mayor ganancia media diaria durante el período de recría tuvieron un número y porcentaje de eyaculados viables más bajos a lo largo de su vida productiva y mayor riesgo de muerte o sacrificio. Estos resultados podrían indicar que la clave para llevar a cabo un desarrollo adecuado durante el período de recría debería basarse tanto en conseguir que los conejos alcancen un grado de madurez apropiado, tanto fisiológica como reproductivamente, así como evitar un excesivo engrasamiento al inicio de su vida productiva. En los ensayos destinados a evaluar los programas de alimentación durante la recría, el uso de una restricción alimentaria en hembras, y especialmente el uso de dietas fibrosas (de 8.5 a 10 MJ ED/kg MS) permiten un desarrollo corporal gradual y adecuado a la edad de cubrición, con suficientes reservas corporales para afrontar el comienzo de la vida reproductiva y mejorando tanto su rendimiento reproductivo como su vida útil. El éxito de estos programas de alimentación de recría depende del momento y la duración de la aplicación de estos, mejorándose con la aplicación de un cambio a un pienso enriquecido energéticamente alrededor del primer apareamiento. En los machos, se observó que un programa de alimentación durante la recría adecuado debería adaptarse a la capacidad de ingesta de estos y a sus necesidades nutricionales en períodos concretos de la recría, consiguiendo así mejoras en algunos parámetros del semen al inicio de su vida reproductiva. En conclusión, tanto un desarrollo temprano adecuado desde la gestación hasta el comienzo de su vida reproductiva, como el uso de programas adecuados de alimentación durante la recría podrían mejorar significativamente el rendimiento reproductivo futuro, así como la esperanza de vida, tanto en conejos he / [CAT] Qualsevol millora en el coneixement tant de la nutrició com del maneig dels futurs conills de criança ha de considerar-se com a prioritari en la producció de conills. No obstant açò, els principals esforços en investigació s'han centrat en aquests animals durant la fase de reproducció pròpiament dita. La hipòtesi inicial d'aquesta tesi va ser que aconseguir un desenvolupament primerenc adequat durant la gestació, lactància, engreix i criança, amb l'ajuda de programes ajustats d'alimentació en alguns d'aquests períodes, milloraria el rendiment reproductiu i la vida útil dels futurs conills reproductors. Per a avaluar aquesta hipòtesi, es van dur a terme dos tipus d'assajos, tant en conills femella de línies maternes, com en mascles de línies seleccionades per a la velocitat de creixement i destinades a la inseminació artificial. El primer d'aquests assajos es va centrar en els diferents patrons de creixement, des del naixement fins al final de la fase de criança, i la seua influència en la carrera reproductiva i la vida útil del conill. En el segon tipus de proves, es va avaluar l'efecte de l'ús de diferents dietes o programes d'alimentació durant el període de criança, en la productivitat a curt i mig termini. Els resultats obtinguts semblen indicar que podríem diferenciar dues fases en el desenvolupament primerenc, d'acord amb els seus efectes sobre el rendiment reproductiu i la vida útil. Mostrar un major desenvolupament corporal des del naixement fins als 63 dies de vida sembla tenir una influència positiva en el grau de maduresa i la productivitat al començament de la seua vida reproductiva, a més de poder millorar la seua supervivència a curt termini, però amb possibles efectes negatius en l'esperança de vida a llarg termini. No obstant açò, el desenvolupament durant el període de sembla tenir un major impacte en la productivitat i l'esperança de vida dels nostres futurs conills reproductors. Les femelles més greixades en la primera inseminació van tenir grandàries de ventrada més xicotets (tant nascuts com deslletats) i un major risc de ser sacrificades que les magres (P<0.05). A més, els mascles que van mostrar un major guany mitjà diari durant el període de criança van tenir un nombre i percentatge d'ejaculats viables més baixos al llarg de la seua vida productiva i major risc de mort o sacrifici. Aquests resultats podrien indicar que la clau per a dur a terme un desenvolupament adequat durant el període de criança hauria de basar-se tant a aconseguir que els conills aconseguisquen un grau de maduresa apropiat, per a afrontar els futurs desafiaments productius, com evitar un excessiu greixatge a l'inici de la seua vida productiva. En els assajos destinats a avaluar els programes d'alimentació durant la criança, l'ús d'una restricció alimentària en femelles, i especialment l'ús de dietes fibroses (de 8.5 a 10 MJ ED/kg MS) permeten un desenvolupament corporal gradual i adequat a l'edat de cobriment, amb suficients reserves corporals per a afrontar el començament de la vida reproductiva i millorant tant el seu rendiment reproductiu com la seua vida útil. L'èxit d'aquests programes d'alimentació de criança depèn del moment i la durada de l'aplicació d'aquests, millorant-se amb l'aplicació d'un canvi a un pinso enriquit energèticament al voltant del primer cobriment. En els mascles, es va observar que un programa d'alimentació durant la criança adequat hauria d'adaptar-se a la capacitat d'ingesta d'aquests i a les seues necessitats nutricionals en períodes concrets de la criança, aconseguint així millores en alguns paràmetres del semen a l'inici de la seua vida reproductiva. En conclusió, tant un desenvolupament primerenc adequat des de la gestació fins al començament de la seua vida reproductiva, com l'ús de programes adequats d'alimentació durant la criança podrien millorar significativament el rendiment reproductiu futur, així com l'esperança / [EN] Any improvement on the knowledge of both nutrition and management of the future rabbit breeders should be considered as crucial. However, main research efforts have been focused on animals during reproduction phase. The initial hypothesis of this thesis was that achieving an adequate early development during young rabbits' gestation, lactation, fattening and rearing, with the help of fitted feeding programmes in some of these periods, would be improved reproductive performance and lifespan of the future breeding rabbits. To evaluate this hypothesis, two types of trials, both in rabbit females from maternal lines selected for litter size at weaning and males from paternal lines selected for growth rate and intended on artificial insemination, were carried out. The first of these trials were mainly focused on the different growth patterns, from birth to the end of the rearing age, and their influence on rabbit's reproductive career and lifespan. In a second type of trials, the effect of the use of different diets or feeding programs during the rearing period in the performance in the short- medium-term was evaluated. The results obtained from the evaluation of the different growth patterns trials seem to indicate that, we could differentiate two parts on the early development according to their effects on reproductive performance and lifespan. To show a greater body development from birth to 63 days of life seems to have a positive influence on the maturity degree and productivity at the beginning of their reproductive life, as well as being able to improve their survival in the short-term, but it could be even negative for long-term lifespan. However, the development during the rearing period (from 63 days of life to the beginning of reproduction career) seems to have a higher impact on the productivity and lifespan of our rabbit breeders. Fatter rabbit females at first insemination had smaller litter sizes (born and weaned) and a higher risk of being culled (+13% per positive change in mm of perirenal fat) than lean ones (P<0.05). Also, rabbit males that showed a greater average daily gain during rearing period had a lower number and percentage of profitable ejaculates through it productive life (-10.1 and -4.9% per each 10 g of daily gain increase, respectively; P<0.05) and higher risk of death or culling (+16.2% per each increase in one standard deviation unit on live weight; P<0.05). These results could indicate that the key to carrying out an adequate development during the rearing period should allow the rabbits to reach an appropriate degree of physiological and reproductive maturity to face the future productive challenges, avoiding an excessive fatness at the beginning of their productive life. The use of a feeding restriction in rabbit females, and especially the use of fibrous diets (from 8.5 to 10 MJ DE/ kg DM) lead a gradual and adequate body development at mating, with enough body reserves to face the beginning of reproduction life and improving their whole reproductive performance and lifespan. The success of these rearing feeding programs depends in the moment and duration of application of them and improved with the application of a nutritional flushing around first mating. In rabbit males, it was observed that an adequate rearing feeding program should adapt it to the male's intake capacity and their nutritional requirements rearing period, especially to their high DP needs at the beginning of rearing period or when their requirements were close to maintenance, to improve some semen parameters at the beginning of their reproduction life. In conclusion, both the adequate early development of future rabbit breeders, from their own gestation to the beginning of their reproductive life, and the use of appropriate rearing feeding programs could significantly improve their future reproductive performance, as well as their life expectancy, both in rabbit females and males. / Martínez Paredes, EM. (2019). Rearing programmes for breeding rabbits. Effect of early development and feeding on future reproductive performance of rabbit females and males [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/124969 / TESIS
13

Expression of Myoepithelial Markers in Mammary Carcinomas of 119 Pet Rabbits

Degner, Sophie, Schoon, Heinz-Adolf, Degner, Sebastian, Baudis, Mathias, Schandelmaier, Claudia, Aupperle-Lellbach, Heike, Schöninger, Sandra 06 April 2023 (has links)
Mammary cancer is a serious health issue in pet rabbits; prognostic factors are unknown. In a normal mammary gland, glandular secretory cells are surrounded by a single continuous layer of myoepithelial cells. In non-invasive mammary carcinomas, tumor cells are delineated by an intact myoepithelial layer, which is gradually lost to invasive carcinomas. The main aim of this study was to determine in rabbit mammary carcinomas (n = 119) the expression of myoepithelial markers that have prognostic significance in human cancer. Results show that all cases contained some retained myoepithelial cells. In 93% of the tumors, neoplastic cells expressed the myoepithelial marker calponin. There was a statistically significant association between higher percentages of calponin-containing cancer cells and histological features indicative of a better tumor differentiation, i.e., a lower proliferation of tumor cells, an increased percentage of tubular growth within the tumor, and a lower tumor grade, respectively. These results suggest that rabbit mammary carcinomas develop from progression of non-invasive cancer forms, and that calponin expression in cancer cells likely represents a favorable prognostic factor. The latter hypothesis has to be confirmed in long-term follow-up studies.
14

A Review on Mammary Tumors in Rabbits: Translation of Pathology into Medical Care

Schöniger, Sandra, Degner, Sophie, Jasani, Bharat, Schoon, Heinz-Adolf 06 April 2023 (has links)
In recent years mammary cancer has been increasingly recognized in pet rabbits. In addition to uterine carcinomas—the most common tumor of female rabbits—mammary cancer can also markedly reduce the life expectancy of pet rabbits. The aim of this review is to raise awareness for these tumors and to report recent progress in related research. Their detailed characterization will likely improve medical care for affected rabbits. Moreover, study results will contribute to comparative pathology and may reveal if the rabbit is a suitable model for certain types of breast cancer in humans. Available information suggests that most invasive cancer cases develop through stepwise progression from non-invasive forms. Thus, early recognition will likely improve a complete cancer cure. So far, the only treatment option is surgical excision and prognostic factors are unknown. Recent investigations have identified tumor features with likely prognostic value. They have also revealed differences and similarities to mammary tumors in other species and breast cancer in women. Despite these initial data, continued research is necessary to gain more insights into the development of these tumors and their molecular features.
15

Sällskapskaninens välfärd i Sverige : Djurhållning och dess inverkan / The welfare of the companion rabbit in Sweden : Animal husbandry and its impact

Ramström, Louise January 2021 (has links)
Den domesticerade kaninen (Oryctolagus cuniculus) är idag ett vanligt sällskapsdjur världen över. Sällskapskaniner framhålls som det tredje mest populära sällskapsdjuret i Sverige, efter hund och katt. Trots detta behandlar endast en mycket liten andel av den övergripande forskningen inom ämnet hälsa- och välfärd just kanin. Den här studien har undersökt inverkan på sällskapskaninens välfärd av kaninägare med eller utan tidigare erfarenhet, sjukdomsbild, samt kaninägares preferenser - och om detta är faktorer som påverkar sällskapskaninens välfärd i Sverige. Studien genomfördes som en enkätundersökning, besvarad av 147 deltagare bosatta i Sverige. Enkäten publicerad i nätverkstjänsten Facebook och fanns tillgänglig under tidsperioden 23:e April - 7:e Maj, 2021. Mer än 50 % av deltagarna saknade erfarenhet och kunskap om kaniner innan de skaffade sin första kanin. Över 37 % höll sina kaniner ensamlevande, och mer än 21 % inhyste sina kaniner i bur. Behovet av veterinärvård utgjordes totalt av nästan hälften av kaninerna, och de kaniner som hölls inomhus eller frigående hade störst behov. Det fanns en skillnad i behovet av veterinärvård hos olika raskategorier, där kategorin små raser var högst representerad. Antalet kaniner som drabbades av olika typer av hälsorelaterade problem varierade, men sjukdomar kopplade till avelsrelaterad problematik utgjordes av nästan 1/3 av alla sjukdomar. Den vanligaste raskategorin att hålla var dvärgraser som hölls av nästan 60 % av alla deltagare, och den vanligaste orsaken till att välja just den raskategorin utgjordes av dess storlek. Den här studien visade att det finns faktorer i kaninägarens djurhållning som kan kopplas till sällskapskaninens välfärd i Sverige. Avgörande parametrar till detta har lyfts fram som kaninägarens erfarenhet och kunskap om kaniner, hållning och inhysning, samt val av raskategori. Nyckelord: Oryctolagus cuniculus, sällskapskanin, djurhållning, djurvälfärd, djuravel, djuretik / The domesticated rabbit (Oryctolagus cuniculus) is today a common pet worldwide. Pet rabbits are highlighted as the third most popular pet in Sweden, after dogs and cats. Despite this, only a very small proportion of the overall research in the subject of health and welfare deals with rabbits. This study has examined the impact on the companion rabbit's welfare of rabbit owners with or without previous experience, disease picture, and rabbit owners' preferences - and whether these are factors that affect the companion rabbit's welfare in Sweden. The study was conducted as a survey, answered by 147 participants living in Sweden. The survey was published in the network service Facebook and found available during the period 23 April - 7 May, 2021. More than 50% of the participants lacked experience and knowledge about rabbits before acquiring their first rabbit. Over 37% kept their rabbits alone, and more than 21% housed their rabbits in cages. The need for veterinary care accounted for a total of almost half of the rabbits, and the rabbits kept indoors or free-running were most in need. There was a difference in the need for veterinary care in different breed categories, where the category small breeds was most represented. The number of rabbits suffering from various types of health-related problems varied, but diseases linked to breeding-related problems accounted for almost 1/3 of all diseases. The most common breed category to keep was dwarf breeds held by almost 60% of all participants, and the most common reason for choosing that particular breed category was its size. This study showed that there are factors in the rabbit owner's animal husbandry that can be linked to the companion rabbit's welfare in Sweden. Decisive parameters for this have been highlighted as the rabbit owner's experience and knowledge of rabbits, posture and housing, as well as the choice of breed category. Keywords: Oryctolagus cuniculus, companion rabbit, animal husbandry, animal welfare, animal breeding, animal ethics
16

Experimentální infekce Oryctolagus cuniculus motolicí Fascioloides magna / Experimental infection of Oryctolagus cuniculus with fluke Fascioloides magna

Melounová, Klára January 2015 (has links)
Fasioloides magna is a trematode parasitizing in the liver parenchyma of ruminants. Its life cycle is associated with the humid environment and includes intermediate freshwater snail hosts from family Lymnaeidae. According to the ability of host to form a certain type of a pseudocyst during fascioloidosis, they can be,divided in three groups, specific definitive hosts (red deers, fallow deers, roe deers), nonspecific definitive hosts (cattle, wild boars and elks) and atypical hosts (sheeps and goats). Beside the natural infections also the experimental infections of other potential host species has been realized (chamois, llama and bighorn sheep and traditional laboratory animals such as mice, guinea pigs, rats and rabbits). In the context of different diseases, many changes in infected organism can occur. These can be qualitatively and quantitatively evaluated. Similarly, during fascioloidosis the changes associated with the presence of the parasite in the host's body is possible to monitor, e.g. antibody production, increase in the number of eosinophils, release of eggs in faeces, internal bleeding, or the level liver damage. The liver damage is corresponding primarily to biochemical parameters of blood, not only the liver enzymes, but also other blood components, like blood proteins, lipids,...

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