Invasões biológicas representam hoje a segunda maior ameaça à biodiversidade, e o homem desempenha papel fundamental na introdução de espécies exóticas potencialmente invasoras. O cachorro (Canis lupus familiaris) é uma dessas espécies. Presente em todos os continentes, é o carnívoro mais abundante do mundo, e pode causar impactos à fauna nativa através de efeitos letais e não letais da predação, competição, hibridização e transmissão de doenças, além de ser potencialmente importante na epidemiologia de zoonoses. Em áreas rurais, que concentram grande parte dos remanescentes de vegetação nativa no mundo, os cachorros são frequentemente criados soltos e circulam livremente, intensificando a chance de contato com a fauna nativa. Nesse trabalho, avaliamos a importância relativa de fatores associados a atributos individuais (sexo, idade, condição de saúde, comportamento exploratório, tamanho e raça), formas de manejo (incentivo do dono à movimentação, motivo para a criação, confinamento e frequência de alimentação) e contexto ambiental (proximidade à mata nativa) para determinar a chance de cachorros visitarem remanescentes florestais em paisagens fragmentadas de Mata Atlântica. Selecionamos oito paisagens de 2830 ha cada, nas quais visitamos todas as construções em áreas rurais a fim de entrevistar, através da aplicação de questionário, os responsáveis pela criação de cachorros e fotografar os cachorros. Utilizamos a imputação múltipla para estimar os dados faltantes (comuns em dados obtidos via questionários), gerando 10 conjuntos de dados imputados que foram analisados separadamente. Por meio de seleções de modelos através do Critério de Informação de Akaike, comparamos modelos candidatos com até cinco variáveis independentes para determinar a chance de cachorros visitarem remanescentes florestais. Nossos resultados nos permitem afirmar que quatro fatores - dois associados a atributos individuais e dois associados a formas de manejo - atuam em conjunto para determinar a chance de cachorros visitarem remanescentes florestais em paisagens rurais da Mata Atlântica. Cachorros maiores, mais exploradores, que recebem mais incentivo a se movimentar e que passam menos tempo confinados têm maior chance de visitar remanescentes florestais. A maior importância de atributos individuais e da forma de manejo está de acordo com a grande variação fenotípica existente entre cachorros e a variedade de modos como são manejados. Entre os atributos individuais, tanto características físicas como comportamentais são importantes, enquanto os aspectos chave da forma de manejo são aqueles mais diretamente relacionados à movimentação dos cachorros. Independentemente do tempo de confinamento, o incentivo do dono à movimentação do cachorro, em particular o estímulo para que o cachorro o acompanhe em visitas a remanescentes florestais, é fundamental. O contexto ambiental, em especial a proximidade do domicílio a áreas de mata nativa, por sua vez, é irrelevante dada a alta mobilidade dos cachorros. Nossos dados sugerem que a densidade de cachorros em paisagens rurais de Mata Atlântica é uma ordem de magnitude mais alta do que a de carnívoros de médio porte silvestres relativamente comuns, que muitos cachorros já tiveram contato direto com espécies silvestres, e que a vacinação e outras medidas profiláticas são relativamente incomuns. Todos esses dados indicam o potencial de efeitos negativos, tanto para a fauna silvestre como para o homem. Programas de redução destes impactos devem incluir tanto aspectos veterinários, como a expansão de campanhas públicas de profilaxia para além da vacinação antirrábica, quanto aspectos sociais, como a divulgação e conscientização dos potenciais problemas ocasionados pela entrada de cachorros em áreas de vegetação nativa, visando mudanças nas crenças, atitudes e comportamento da população humana / Biological invasions are today the second greatest threat to biodiversity, and humans play a significant role in the introduction of potentially invasive exotic species. The dog (Canis lupus familiaris) is one of such species. Distributed across all continents, the dog is the most abundant carnivore in the planet, and can impact wildlife through lethal and non-lethal effects of predation, competition, hybridization and disease transmission, besides being potentially important in the epidemiology of zoonoses. In rural areas where most remnants of native vegetation around the world are concentrated, most dogs are free-ranging, enhancing the chance of interactions with wildlife. Here, we evaluated the relative importance of factors associated with individual traits (sex, age, health condition, exploratory behaviour, size and breed), management (owner\'s incentive to movement, motive for raising, confinement and feeding frequency), and environmental context (proximity to native forest) to determine the chance of dogs visiting forest remnants in Atlantic Forest fragmented landscapes. We selected eight landscapes of 2830 ha each, where we visited all constructions in rural areas in order to interview dog owners by applying a questionnaire and to photograph dogs. We used multiple imputation to estimate missing data (common in data obtained through questionnaires), obtaining 10 imputed datasets that were analyzed separately. We compared candidate models with up to five independent variables to determine the chance of dogs visiting forest remnants through the Akaike Information Criterion. Our results indicate that four factors - two associated with individual traits and two associated with management - work together to determine the chance of dogs visiting forest remnants in Atlantic Forest rural landscapes. Larger dogs, and those that exhibit exploratory behaviour, are more stimulated to move or confined for shorter periods have greater chance of visiting forest remnants. The greater importance of factors associated with individual traits and management is in accordance with the ample phenotypic variation among dogs and the variety of ways they can be managed. Among individual traits, both morphological and behaviour characteristics are important, whereas the key aspects of management are those directly related to dog movement. Irrespective of the time confined, the owner\'s incentive to movement, in particular taking the dog to the forest, is a crucial aspect. In contrast, the environmental context, especially the proximity of the household to native forest, is irrelevant given the vagility of dogs. Our results suggest that the density of dogs across rural landscapes in the Atlantic forest is at least one order of magnitude higher than the density of relatively common medium-sized native carnivores, that several dogs have already had direct contact with wild species, and that vaccination and other prophylactic measures are relatively uncommon. All of these highlight the potential for negative effects on both wildlife and human population. Plans to reduce these effects should include not only veterinarian aspects, such as the expansion of public prophylactic campaigns beyond rabies vaccination, but also social aspects, such as the dissemination of information on the problems caused by dogs visiting native vegetation, aiming at changing people\'s beliefs, attitudes and behaviour

Abstract Hosts and pathogens are involved in a continuous evolutionary arms race, where pathogens attack and hosts defend themselves. The main tools for winning the race are natural selection and the genetic diversity that selection acts on. However, in small populations natural selection may be ineffective. Therefore, the genes taking part in immune defense may lack adaptability to new or changing pathogens. Major histocompatibility complex (MHC) is an important genomic region that includes highly polymorphic immune defense genes. In this doctoral thesis, I studied the natural selection and genetic diversity of MHC class II genes in dogs and Finnish wolves. I also used dog MHC diversity to estimate the number of founding wolves in dog domestication. The Finnish wolf population declined rapidly in size due to excessive hunting from the late 19th century until the early 20th century. After decades of a very small population size, the population started recovering in the mid-1990s. This study shows that, despite the fluctuations in population size, the diversity of the MHC loci in the Finnish wolf has remained high and comparable to the larger neighboring Russian Karelian wolf population. Unlike the neutral genetic markers, the MHC loci of the Finnish and Russian Karelian populations have not differentiated. These results indicate similar balancing selection acting on the MHC loci of the two wolf populations. In dogs, the strength of natural selection is likely weakened by artificial selection and veterinary care. The potential phases of natural selection would be during embryogenesis and fetal development. However, no strong signs of prenatal selection were found in this study. MHC diversity was estimated to be higher in Asian dogs than in dogs from Europe. A simulation study indicated a minimum of 500 founding wolves for the modern dog population. Dog MHC diversity implies an Asian origin for domestication from a large and diverse wolf population. Both natural selection and demography have an influence on the genetic diversity of a species. In small populations, random genetic drift is enforced. However, in loci with important fitness impacts, selection may be particularly strong and outweigh drift, as demonstrated in the MHC loci of a small wolf population in this study. / Tiivistelmä Isäntä ja taudinaiheuttajat käyvät jatkuvaa kaksinkamppailua, jossa taudinaiheuttajat hyökkäävät ja isäntä puolustautuu. Kamppailussa menestymiseen tarvitaan geneettistä monimuotoisuutta sekä sen pohjalta toimivaa luonnonvalintaa. Pienissä populaatioissa luonnonvalinnan teho voi kuitenkin heikentyä, jolloin immuunipuolustukseen osallistuvat geenit eivät kykene sopeutumaan uusiin tai muuttuneisiin taudinaiheuttajiin. MHC-alueella (major histocompatibility complex) sijaitsee suuri joukko monimuotoisia immuunipuolustukseen osallistuvia geenejä. Väitöskirjassani tutkin luokan II MHC-geeneihin kohdistuvaa luonnonvalintaa ja niiden geneettistä monimuotoisuutta koirilla ja Suomen susilla. Arvioin myös koiran kesyttämisprosessiin osallistuneiden susien määrää nykykoiran MHC-monimuotoisuuden pohjalta. Suomen susipopulaation koko pieneni nopeasti voimakkaan metsästyksen vuoksi 1800-luvun lopulta 1900-luvun alkuun. Populaatio pysyi hyvin pienenä useita vuosikymmeniä, kunnes se alkoi elpyä 1990-luvun puolivälissä. Tutkimus osoitti, että populaatiokoon vaihteluista huolimatta Suomen susien MHC-geenien monimuotoisuus on säilynyt korkeana ja on vastaavalla tasolla kuin Venäjän Karjalan susipopulaatiossa. Suomen ja Venäjän Karjalan susipopulaatioiden MHC-geenit eivät ole erilaistuneet, vaikka populaatiot poikkeavat toisistaan neutraalien geenimerkkien suhteen. Samanlainen tasapainottava valinta näyttäisi kohdistuvan näiden susipopulaatioiden MHC-geeneihin. Keinotekoinen valinta ja eläinlääketieteellinen hoito todennäköisesti heikentävät koirien MHC-geeneihin kohdistuvaa luonnonvalintaa. Luonnonvalinta voisi yhä vaikuttaa alkion- ja sikiönkehityksen aikana, mutta tästä ei tutkimuksessa löytynyt todisteita. MHC-muuntelun määrän arvioitiin olevan suurempaa aasialaisissa kuin eurooppalaisissa koirissa. Simulaatiotutkimuksen mukaan nykyisen koirapopulaation perustamiseen olisi tarvittu vähintään 500 sutta. Tulokset viittaavat koiran kesyttämisen tapahtuneen Aasiassa suuresta ja monimuotoisesta susipopulaatiosta. Sekä luonnonvalinta että demografia vaikuttavat lajien geneettiseen monimuotoisuuteen. Pienissä populaatioissa satunnaisajautuminen voimistuu. Valinta voi kuitenkin olla erityisen voimakasta ja voittaa satunnaisajautumisen geeneissä, joilla on erityisen tärkeä vaikutus yksilön kelpoisuuteen, kuten tutkimuksessa osoitettiin pienen susipopulaation MHC-geenien kohdalla.

Please read the abstract in the section 08summary of this document / Thesis (PhD (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

Die vorliegende epidemiologische Studie umfaßte 153 Hunde aus der Nähe von Athen, Griechenland. Um die Prävalenz arthropogener Infektionen abschätzen zu können, wurden Serumproben auf Antikörper gegen Leishmania infantum, Ehrlichia canis und Borrelia burgdorferi sowie auf Antigene von Dirofilaria immitis überprüft. Blutausstriche wurden auf das Vorkommen von Babesia canis und Hepatozoon canis untersucht. Außerdem wurden von den Hunden abgesammelte Zecken bestimmt. Bei 126 Hunden erfolgte eine klinische Allgemeinuntersuchung. Des weiteren wurden die serologischen Testverfahren ELISA und IFAT für den Nachweis von Antikörpern gegen Borrelia burgdorferi miteinander verglichen. Insgesamt waren 94 (61,4 %) der 153 untersuchten Hunde infiziert, 63 (41,2 %) Hunde wiesen Antikörper gegen Ehrlichia canis auf. Infektionen mit Borrelia burgdorferi wurden im ELISA insgesamt bei 43 (28,1 %), im IFAT bei 35 (22,9 %) Tieren nachgewiesen. Außerdem konnte bei 28 (18,3 %) Tieren eine Infektion mit Leishmania infantum und bei 20 (13,1 %) mit Dirofilaria immitis gefunden werden. Ein Nachweis von Babesia canis im Blutausstrich gelang bei vier (2,6 %) Hunden, von Hepatozoon canis nur bei einem (0,7 %) Hund. Für keinen der untersuchten Infektionserreger konnten signifikante Alters-, Geschlechts- oder Rasseprädispositionen festgestellt werden. Die Infektionsraten mit Leishmanien, Babesien, Dirofilarien und Borrelien waren bei den im Tierheim lebenden Hunden geringer als bei den Streunern. Vierundvierzig (28,8 %) der 153 getesteten Hunde waren gleichzeitig mit zwei, drei oder vier durch Arthropoden übertragene Erregerarten infiziert. Zweifachinfektionen kamen bei 29 (19,0 %), Dreifachinfektionen bei sieben (4,6 %) und Vierfachinfektionen bei acht (5,2 %) Tieren vor. In der Regel war das Risiko für Hunde, einen Erreger zu beherbergen, höher, wenn bereits eine Infektion mit einem anderen Erreger vorhanden war. Insgesamt waren 28 (18,3 %) Streuner und 15 (9,8 %) Tierheimhunde von Mehrfachinfektionen betroffen. Von den 94 mit mindestens einem der berücksichtigten Erreger infizierten Hunden wurden 75 (79,8 %) einer klinischen Untersuchung unterzogen. Dreiunddreißig (44,0 %) dieser Tiere zeigten Krankheitserscheinungen. Bei 21 (67,7 %) der 31 klinisch untersuchten und mit mehreren Erregern gleichzeitig infizierten Hunde konnten Krankheitssymptome diagnostiziert werden. Von 44 klinisch untersuchten Tieren, die nur mit einem Erreger infiziert waren, zeigten 12 (27,3 %) klinische Symptome. Die diagnostizierten Symptome waren bei allen untersuchten Erregern von einer starken Variabilität geprägt. Die Übereinstimmung der Testsysteme IFAT und ELISA für den Nachweis von Antikörpern gegen Borrelia burgdorferi lag bei 92,2 %. Die Testverfahren sind damit als nahezu gleichwertig anzusehen, wobei der ELISA etwas sensitiver zu sein scheint. Eine Infektionsgefahr besteht demnach in Griechenland vor allem für Ehrlichia canis, Borrelia burgdorferi und Leishmania infantum, aber auch für Infektionen mit Dirofilaria immitis besteht ein Risiko. Infektionen mit Babesia canis kommen in dieser Region seltener vor, es muss jedoch insbesondere bei geschwächten oder in Deutschland geborenen und somit hochempfänglichen Tieren mit Erkrankungen gerechnet werden. Hepatozoon canis ist nach den vorliegenden Ergebnissen in der Umgebung von Athen von geringer Verbreitung. Ein Rückschluß vom klinischen Bild auf das Vorliegen einer Infektion mit einem bestimmten Erreger kann aufgrund der Variabilität der Symptome in Verbindung mit häufig auftretenden Mehrfachinfektionen nicht gezogen werden. Die Möglichkeit von gleichzeitig vorliegenden Infektionen sollte in der Diagnostik und Therapie unbedingt berücksichtigt werden. Gute Haltungsbedingungen und eine tierärztliche Überwachung und Prophylaxe reduzieren offensichtlich die Inzidenz von Infektionen mit arthropodenübertragenen Erregern. Die überwiegende Anzahl (449 von 457 Exemplaren) der bestimmten Zecken gehörte der Art Rhipicephalus sanguineus an. Es wurden sechs Nymphen und 443 adulte Tiere gefunden. Die adulten Tiere verteilten sich auf 243 männliche und 200 weibliche Zecken. Bei acht Zecken handelte es sich um weibliche Ixodes ricinus. Bei aus Griechenland stammenden Hunden wie auch bei Tieren, die sich reisebegleitend dort aufgehalten haben, muss mit einer starken Infestation mit Rhipicephalus sanguineus gerechnet werden. Da Rhipicephalus sanguineus der Vektor für Ehrlichia canis, Babesia canis vogeli und Hepatozoon canis ist, sollten Prophylaxemaßnahmen eine geeignete Zeckenbekämpfung einbeziehen. / 153 dogs from the environs of Athens, Greece, were surveyed for tick infestation and arthropod borne infections. Serology was performed for Leishmania infantum, Dirofilaria immitis, Ehrlichia canis and Borrelia burgdorferi and bloodfilms were microscopically examined for Babesia canis and Hepatozoon canis. Ticks collected from the dogs were differentiated. 126 dogs underwent clinical examination. Suitability of an indirect immunofluorescent antibody assay (IFAT) and an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of antibodies to Borrelia burgdorferi was compared. Altogether 94 (61.4 %) dogs were infected with an arthropod borne pathogen, 63 (41.2 %) produced antibodies to Ehrlicha canis. ELISA detected Borrelia burgdorferi infection in 43 (28.1 %) dogs while IFAT was positive in 35 (22.9 %). 28 (18.3 %) dogs were infected with Leishmania infantum and 20 (13.1 %) with Dirofilaria immitis. Babesia canis was found in blood smears of four (2.6 %) dogs, Hepatozoon canis was detected only in one case (0,7 %). No association was found between the breed, age or sex of the dogs and any of the tested pathogens. The rate of infection with Leishmania, Babesia, Dirofilaria or Borrelia was lower in dogs living in the animal shelter than in those living as strays. 44 (28.8 %) of the 153 dogs examined were infected concurrently with two (n = 29, 19,0 %), three (n = 7, 4,6 %) or four (n = 8, 5,2 %) arthropod borne pathogens. In general the risk of infection was higher in dogs that were already infected with another pathogen. Altogether 28 (18.3 %) of the strays and 15 (9.8 %) of the dogs living in the animal shelter had a multiple infection. 75 of the 94 dogs infected with at least one of the tested pathogens were examined clinically. 33 (44.0 %) showed clinical symptoms. In 21 (67,7 %) of the 31 clinically examined dogs with multiple infection symptoms of disease were diagnosed. Twelve (27.3 %) of the 44 clinically examined dogs that were only infected with one pathogen had symptoms of some kind. Clinical symptoms varied considerably irrespective of the causative agent. The concordance of the IFAT and the ELISA for the diagnosis of Borrelia burgdorferi was 92.2 %. The serologic diagnosis of Borrelia burgdorferi with IFAT or ELISA can be regarded similarly suitable although ELISA seems to be somewhat more sensitive. In conclusion the risk of infection in Greece is particularly high for Ehrlichia canis, Borrelia burgdorferi and Leishmania infantum and Dirofilaria immitis as well. Babesia canis is obviously transmitted less. However dogs in poor condition or born in non endemic areas may acquire babesiosis in Greece. According to the results of this study Hepatozoon canis seems to be of negligible relevance in Greece. Due to the variability of the clinical symptoms and the frequent occurrence of multiple infections diagnosis based on the clinical picture only is not possible. Multiple infections should also be considered with respect to treatment. Infections with arthropod borne pathogens seem to occur less often in prophylactically treated dogs living under good conditions. Most of the examined ticks were identified as Rhipicephalus sanguineus (449 out of 457 specimens). Six nymphs and 419 adults were found. Of the adult Rhipicephalus sanguineus ticks 243 were males and 200 were females. Eight of the ticks were female Ixodes ricinus. In dogs originating from Greece as well as in dogs having accompanied tourists into Greece infestation with Rhipicephalus sanguineus is probable. As Rhipicephalus sanguineus is known to transmit Ehrlicha canis, Babesia canis vogeli and Hepatozoon canis prophylactic measures should include a suitable tick-control.

Karolina Suková Abstract People have been living with dogs (Canis familiaris) in close symbiotic relationship for many thousands of years. Such a kind of coexistence cannot get along without certain risk factors. Although aggression is a natural and wide spread phenomenon in the animal kingdom, manifestation of canine aggression toward people is a public health problem which has to be resolved. Dog bites can cause traumatic injuries to victims and decrease the quality of life or even cause the loss of life to the animal. Therefore there is a serious need to determine the risk factors of dog attacks to people and provide effective preventive strategies to this problem. We consider two kinds of risk factors to be fundamental in this respect: factors depend on the dog (e.g. age, breed, sex and size) and factors depend on the owner (e.g. method of training, prior experience with care of dogs, knowledge of natural behavior of dog, time dedicated to dog etc.). Our study examined this risk factors using a questionaire. Seventy two respondents (owners of both aggressive and non-aggressive dogs) participated on our study. Our results suggest that owner's knowledge of natural behavior of dog, time which the owner dedicates to his dog and sex of the dog correlate significantly with canine aggression toward people. Key...

La toxocariasis humana se ha convertido en un relevante problema, ya que al pasar de los años se ha incrementado en la población considerablemente, esta infección es generada por la alta exposición de las heces caninas. Estos desechos al no ser adecuadamente tratados generan contaminación ambiental y afecta la salud de las personas. En Lima, el distrito más crítico por dicha problemática es San Juan de Lurigancho debido a la mayor población canina y la falta de cultura de recojo de las heces caninas en los parques públicos. En el presente proyecto de investigación se propone un modelo de cadena de suministro para producir biofertilizante y biogás, utilizando las heces caninas, ya que poseen un gran potencial de fertilización orgánica que no es aprovechado por la sociedad, la cual es una oportunidad para promover el desarrollo socioambiental. Es preciso señalar que esta propuesta se distingue a otros proyectos, ya que muestra el cumplimiento de los aspectos económicos y socioambientales, con el uso de tecnologías limpias como son los biodigestores. / Human toxocariasis has become a relevant problem, since over the years it has increased in the population considerably, this infection is generated by the high exposure of canine feces. These wastes, when not properly treated, generate environmental pollution and affect people's health. In Lima, the most critical district for this problem is San Juan de Lurigancho because of the larger canine population and the lack of culture to collect dog feces in public parks. In this research project, a supply chain model is proposed to produce biofertilizer and biogas, using dog feces, since they have a great potential for organic fertilization that is not used by society, which is an opportunity to promote the socio-environmental development. It should be noted that this proposal distinguishes itself from other projects, since it shows compliance with economic and socio-environmental aspects, with the use of clean technologies such as biodigesters. / Trabajo de Suficiencia Profesional

No description available.

We present distances and kinematics and look at the possible populations for the blue plume (BP) stars in the Canis Major Overdensity (CMa). We conducted a medium resolution spectral survey on the BP stars (N=303) in CMa (centered at l = 238° ; b = -8°) using the data from AAOmega Spectrograph. We used a modified version of the Statistics-sensitive Non-linear Iterative Peak-clipping (SNIP) algorithm to normalize our fluxed absorption spectra. After determining the radial velocities from measurements of strong absorption features for the stars we use a Bayesian analysis of spectral feature strengths and photometric colors to determine Teff, Logg and [Fe/H]. Our procedure makes use of grid for model synthetic spectra computed using SPECTRUM with Atlas9 model atmospheres and Kurucz model colors. We determine the absolute magnitude using the stellar parameters and BaSTI isochrones and compute distances and ages for the BP stars. Our analysis of the BP stars indicates Teff ranging from 6500K to 8000K, metallicity ranging from 0.0 to -1.0 with an average of -0.5. We found for this temperature range that the surface gravity of the stars could not be well constrained. From the spatial and kinematics results we found that most of the stars are thick disk stars with a small mixture of thin disk stars. The stars are most likely a mixture of thick disk blue stragglers and normal A-type stars preferentially seen to greater depths due to the low dust extinction in this location of the Galaxy.

Basic stellar atmospheric parameters, such as effective temperature, surface gravity, and metallicity plays a vital role in the characterization of various stellar populations in the Milky Way. The Stellar parameters can be measured by adopting one or more observational techniques, such as spectroscopy, photometry, interferometry, etc. Finding new and innovative ways to combine these observational data to derive reliable stellar parameters and to use them to characterize some of the stellar populations in our galaxy is the main goal of this thesis. Our initial work, based on the spectroscopic and photometric data available in literature, had the objective of calibrating the stellar parameters from a range of available flux observations from far-UV to far-IR. Much effort has been made to estimate probability distributions of the stellar parameters using Bayesian inference, rather than point estimates. We applied these techniques to blue straggler stars (BSSs) in the galactic field, which are thought to be a product of mass transfer mechanism associated with binary stars. Using photometry available in SDSS and GALEX surveys we identified 85 stars with UV excess in their spectral energy distribution (SED) : indication of a hot white dwarf companion to BSS. To determine the parameter distributions (mass, temperature and age) of the WD companions, we developed algorithms that could fit binary model atmospheres to the observed SED. The WD mass distribution peaks at 0.4M , suggests the primary formation channel of field BSSs is Case-B mass transfer, i.e. when the donor star is in red giant phase of its evolution. Based on stellar evolutionary models, we estimate the lower limit of binary mass transfer efficiency β ~ 0.5. Next, we have focused on the Canis Major overdensity (CMO), a substructure located at low galactic latitude in the Milky Way, where the interstellar reddening (E(B-V )) due to dust is significantly high. In this study we estimated the reddening, metallicity distribution and kinematics of the CMO using a sample of red clump (RC) stars. The averageE(B-V)(~0.19)is consistent with that measured from Schlegel maps (Schlegal et.al. 1998). The overall metallicity and kinematic distribution is in agreement with the previous estimates of the disk stars. But the measured mean alpha element abundance is relatively larger with respect to the expected value for disk stars.

Memoria para optar al Título Profesional de Médico Veterinario / La Brucelosis canina es una enfermedad infectocontagiosa zoonótica causada por la bacteria Brucella canis, afectando principalmente el sistema reproductivo de los perros en ambos sexos. Los signos de esta enfermedad no son evidentes clínicamente e incluso muchos pueden ser asintomáticos. Se caracteriza por producir aborto tardío en hembras y orquitis, epididimitis e infertilidad en machos, pero muchas veces estos signos pueden pasar desapercibidos. En este estudio se determina la sensibilidad analítica de un ensayo PCR tanto para muestras de sangre contaminadas como en cultivos puros para el diagnóstico de brucelosis canina, comparando dos métodos de extracción de DNA. Como resultado se obtuvo que la prueba PCR es capaz de detectar la bacteria en sangre pero obteniendo resultados positivos sólo con uno de los métodos de extracción, detectándose DNA hasta el nivel de los femtogramos / Proyecto FIV 121014019102003