Orientador: Fernando Sebastián Baldi Rey / Resumo: A compreensão de processos regulatórios e organização molecular dos organismos vivos progrediram consideravelmente na última década. As metodologias também evoluíram com o sequenciamento de DNA e RNA e de ferramentas genômicas permitindo a análise de centenas ou milhares de genes, proteínas ou metabólitos. O uso simultâneo dessas informações auxilia na obteção de informações relevantes sobre as variáveis que envolvem as variações fenotípicas de características de interesse. O objetivo do presente estudo foi integrar dados fenotípicos, genotípicos e transcriptômicos em busca de aprimoramento sobre os mecanismos genéticos e metabólicos que determinam o perfil de ácidos graxos na carne de bovinos Nelore, a fim de contribuir para o melhoramento da composição de ácidos graxos da carne. Foram utilizados machos da raça Nelore terminados em confinamento, abatidos com média de idade 24 meses. Amostras do músculo L. thoracis, entre a 12ª a 13ª costela foram coletadas para as análises de perfil de ácidos graxos, extração de RNA e de DNA. Os resultados foram apresentados nos capítulos 2 e 3. No capítulo 2, o objetivo foi identificar genes diferencialmente expressos pelo método RNA-seq e perfil de ácidos graxos no músculo L. thoracis com uso de componentes principais (principal components: PC). Foram selecionados dois grupos de 10 animais, os quais possuíam valores de PC1 e PC2 extremos (Alto x Baixo) para os grupos somatórios de ácidos graxos (AG): ácidos graxos saturados (AGS), ácidos g... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The understanding of regulatory processes and molecular organization of organisms has progressed considerably in the last 10 years.The methodologies also evolved with the sequencing of DNA, RNA and genomic tools allowing the analysis a lot of genes, proteins or metabolites. The simultaneous use of this information should help to obtain relevant information about the variables that result the phenotypic variations of traits of interest. The objective of the present study was to integrate phenotypic, genotypic and transcriptomic studies in order to clarify the genetic and metabolic mechanisms that determine the fatty acid profile in Nelore beef, in order to contribute to the improvement of the fatty acid composition of the meat. Nelore males were used in feedlot, coming from farms that integrate three breeding programs and slaughtered with an average of 24 months. Samples of the L. thoracis muscle between the 12th to 13th rib were collected for analysis of fatty acid profile, RNA and DNA extraction. The results were presented in chapters 2 and 3. In chapter 2, the objective was to identify genes differentially expressed by RNA-seq method and fatty acid profile in the L. thoracis muscle with the use of Principal Components (PC). Two groups of 10 animals were selected, which had PC1 and PC2 extreme values (High x Low) for the fatty acids (FA) groups: saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), omega 3 (n-3) and omega 6 (n-6... (Complete abstract click electronic access below) / Doutor

Em diferentes programas de melhoramento genético, o acompanhamento do progresso genético é essencial para possibilitar ajustes necessários à sua utilização. No Brasil, além de ser considerada uma das raças mais utilizadas para a produção de fêmeas mestiças leiteiras, a raça Gir Leiteiro lidera a lista das raças exportadoras de sêmen. Por conta disso, este estudo objetivou estimar os parâmetros e as tendências genéticas para vinte características de produção, conformação e manejo de animais puros da raça, integrantes do Programa Nacional de Melhoramento do Gir Leiteiro, além das tendências fenotípicas e das tendências genéticas para quatro trajetórias de seleção para produção de leite e de gordura. A metodologia utilizada foi a da Máxima Verossimilhança Restrita em um modelo animal. As tendências genéticas para todas as características foram obtidas via regressão linear das médias dos valores genéticos em função do ano de nascimento dos animais, que em geral, variou de 1935 a 2013. As herdabilidades foram de 0,23 (leite), 0,10 (gordura) e variaram de 0,01 a 0,53 para as características lineares de conformação e manejo. Para produção de leite em 305 dias, houve favorável progresso genético ao longo do tempo, para fêmeas mensuradas (14,04 kg/ano), fêmeas (8,27 kg/ano) e machos (6,12 kg/ano), quanto para as quatro trajetórias de seleção (pais de touros, pais de vacas, mães de touros e mães de vacas). As tendências genéticas para produção de gordura em 305 dias, embora positivas, foram de baixa magnitude. As mudanças genéticas nas características lineares foram em geral, variáveis e inexpressivas, sugerindo que a seleção no Gir Leiteiro tenha sido direcionada essencialmente para maior produção de leite. A provável maior adesão pelos criadores ao uso de reprodutores comprovadamente geneticamente superiores e as melhorias ambientais (nutrição e manejo), possibilitaram incrementos fenotípicos nas produções de leite (55,38 kg/ano) e de gordura (0,91 kg/ano) em bovinos puros da raça Gir Leiteiro no Brasil. / In different breeding programs for genetic improvement, the monitoring of genetic progress is essential to allow for the necessary adjustments to its use. In Brazil, besides being considered one of the most used breeds for the production of crossbred dairy females, the Dairy Gir breed leads the list of semen export breeds. The objective of this study was to estimate parameters and genetic trends for nineteen traits of production, conformation and management of purebred animals of the National Breeding Program for Dairy Gir, in addition to the phenotypic trends and genetic trends for four selection trajectories for the milk yield and fat yield productions. The methodology used was that of Restricted Maximum Likelihood in an animal model. The genetic trends for all traits were obtained through linear regression of the means of genetic values according to the year of birth of the animals, which generally varied from 1935 to 2013. The heritabilities were 0.23 (milk), 0.10 (fat) and ranged from 0.01 to 0.53 for the linear conformation and management traits. The milk yield in 305 days presented favorable genetic progression over time for both mensured females (14.04 kg/year), females (8.27 kg/year) and males (6.12 kg/year), and for the four selection trajectories. The genetic trends for fat yield production in 305 days, although positive, were of low magnitude. The genetic changes in the linear characteristics were in general, variable and inexpressive, suggesting that the selection in Dairy Gir has been directed essentially to a greater milk yield. The probable higher adhesion by breeders to the use of genetically superior breeding herds and environmental improvements (nutrition and management), allowed for phenotypic increases in the milk yield (55.38 kg/year) and fat yield (0.91 kg/year) in the Dairy Gir cattle in Brazil.

La Grotte du Portel-ouest située en Ariège sur la commune de Loubens a été fouillée de 1949 à 1987 par Joseph et JeanVézian. Les fouilleurs ont identifié 20 couches réparties en quatre ensembles archéo-stratigraphiques : un ensemble de base, un premier ensemble moustérien, un deuxième ensemble moustérien et un ensemble du paléolithique supérieur correspondants aux stades isotopiques 5, 4, 3, début 2. Le remplissage a livré 34 restes humains néandertaliens et plus de 200000 vestiges correspondants à de l’industrie, de la macrofaune et de la microfaune. L’étude paléontologique a porté sur les 4495 restes de Bovinae et d’Equidae ; l’étude paléo-environnementale a été réalisée à partir des 12963 restes de macro faune et de 896 rongeurs (NMI) enregistrés à ce jour. L’étude paléontologique des Bovinae (1486 restes) a permis d’identifier deux genres : Bos et Bison. Les comparaisons diachroniques et synchroniques ont conduit à la détermination de Bison priscus mediator et de Bos primigenius primigenius. L’étude paléontologique des Equidae a permis de confirmer la première détermination : Equus caballus germanicus (Gardeisen, 1998). Les comparaisons synchroniques et diachroniques avec les tests statistiques associés (Analyse en Composantes Principales, Classification Ascendante Hiérarchique, et le Test de k means) ont permis de rapprocher ce cheval de ceux de Combe Grenal (couches 1 à 35) et de la Grotte Tournal (niveaux II moyen et II B). Quelques restes trouvés dans le paléolithique supérieur ont pu être attribués à Equus caballus gallicus ; ce cheval est proche des chevaux de Camiac et de Jaurens (Würm récent inférieur) et aussi de Solutré (niveau aurignacien) L’étude paléo-environnementale a révélé à la base du sondage un paysage semi-ouvert, plutôt forestier tempéré correspondant au stade isotopique 5 (interglaciaire Riss-Würm et début Würm ancien) ; le stade 4 est très peu représenté. L’occupation principale du site (F à D) correspond au stade isotopique 3 caractérisé par de très forts changements climatiques avec une succession d’événements de Heinrich (H4, H5) et de phases de réchauffement ou de refroidissement des cycles de Dansgaard-Oeschger (7, 8, 9, 10, 11, 12, 13) dans un paysage très ouvert. La couche B présentant une industrie gravettienne et de l’aurochs correspond certainement à la phase de réchauffement du cycle de Dansgaard-Oeschger 2. / The West cave of the Portel located in Ariége in the commune of Loubens has been excavated between 1949 and 1987 byJoseph and Jean Vézian. The excavators identified 20 layers spread in 4 archeologically stratified groups : the basic group, the first Mousterian group and the second Mousterian group and an ensemble of the superior Paleolithic group corresponding to the isotopic stages 5, 4, 3, beginning 2. The contents excavated from this cave gave us 34 Neanderthal human remains and more than 200 000 artifacts corresponding to the industry, the macrofauna and the microfauna. Paleontological studies have been realized on the 4495 Bovinae and Equidae remains. Environmental Paleolithic studies have been completed from 12963 remains of the macrofuna and from 896 rodents registered to this day (NMI). Bovinae paleontological studies (1486 remains) allowed identification of two genre : Bos and Bison. The diachronic and synchronic comparisons have led to determination of Bison priscus mediator and Bos primigenius primigenius. Equidae paleontological studies have allowed confirmation of the first determination: Equus caballus germanicus (Gardeisen,1998).The diachronic and synchronic comparisons with the statistical tests associated (ACP, CAH, and the test of k means)allowed to bring closer the horse from the Portel to those of the Combe Grenal (layers 1 to 35) and the horses of the Tournal cave (stages II middle and II B). Some remains found in the superior Paleolithic have been attributed to Equus caballus gallicus. This horse resembles the horses of Camiac, of Jaurens (inferior recent Würm) and of Solutré (stage of the Aurignacian). Environmental Paleolithic studies has shown, at the bottom of the contents excavated, a landscape semi open, rather temperate forest corresponding to the isotopic stage 5 (interglacial Riss-Würm and to the beginning or ancient Würm). The isotopic stage 4 is rarely represented. The principal occupation of the site by Neanderthal (F à D) is during the isotopic stage 3 characterized by very great climatic changes with a succession of Heinrich events (H4, H5) and phases of warming or cooling phases of the cycle Dansgaard-Oeschger (7, 8, 9, 10, 11, 12, 13) in a landscape very open, far reaching and vast. The layer B presents one gravettian industry and some Bos, and certainly corresponds to the phase of warming of the cycle Dansgaard-Oeschger 2.

Thesis (Ph.D.)--Mississippi State University. College of Veterinary Medicine. / Title from title screen. Includes bibliographical references.

Resumo: Características de carcaça preditas por ultrassonografia foram incluídas nos programas de avaliação genética, uma vez que estas estão associadas à qualidade e rendimento de carcaça. Neste trabalho, os objetivos foram estimar os parâmetros genéticos e as tendências genéticas para área de olho de lombo (AOL), espessura de gordura subcutânea (EG) e espessura de gordura subcutânea de garupa (EGP8), peso corporal aos 210 (P210) e aos 365 (P365) dias de idade em bovinos da raça Nelore. Foram analisados dados de animais nascidos entre 1998 e 2008, oriundos de fazendas participantes do Programa de Melhoramento Genético da Raça Nelore (Nelore Brasil). As estimativas dos componentes de (co) variância, dos parâmetros genéticos e valores genéticos para as características estudadas foram obtidas pelo método da máxima verossimilhança restrita, sob modelo animal multi-característica. Para as características de peso as estimativas de herdabilidade genética direta e materna foram: 0,26 ± 0,003 e 0,18 ± 0,01, para P210 e 0,39 ± 0,02 e 0,05 ± 0,01, para P365. As estimativas de herdabilidade para AOL, EG e EGP8 foram iguais a 0,28 ± 0,03; 0,21 ± 0,02; 0,25 ± 0,03, respectivamente. Mudanças significativas nos valores genéticos médios anuais das características de carcaça indicaram que estas estão sendo indiretamente influenciadas pelo índice de seleção aplicado para estes rebanhos / Abstract: Carcass traits by ultrasound measurements were included in genetic evaluation programs because they are associated with carcass yield and quality. This study aimed to estimate genetic parameters and genetic trends for back fat thickness (BF), rump fat thickness (RF), rib-eye area (REA) and body weight at 210 (BW210) and 365 (BW365) days of age. It data from animals whose herds participating in the Nelore breeding program (Nelore Brasil) born between 1998 and 2008, were used. Genetic parameters, (co)variance components and breeding values were estimated for each trait, in multi traits analysis, using maximum restricted likelihood method. Heritability estimates were equal to 0.28 ± 0.03 (REA); 0.21 ± 0.02 (BF) and 0.05 ± 0.01 (RF). In the growth traits the direct and maternal heritability estimates were respectively 0.26 ± 0.003; 0.18 ± 0.01 for BW210 and 0.39 ± 0.021; 0.05 ± 0.010 for BW365. Significant changes in the annual breeding values indicated that the carcass traits are being indirectly influenced by the selection index / Orientador: Danísio Prado Munari / Coorientador: Claudia Cristina Paro de Paz / Banca: Joslaine Noely dos Santos Gonçalves Cyrillo / Banca: Fernando Sebastián Baldi Rey / Mestre

Most research into Bergson's influence to date has failed to take enough account of the philosopher's interest in the spiritual of meta-physical dimension of life. In seeking to interpret Bergson's thought many have focused upon 'la durée réelle' or 'l'élan vital' as the key concepts in his whole philosophy. If, instead, one were to begin with Bergson's main continuing preoccupation at first inchoate and only later more fully developed with spiritual activity in life, then the whole philosophy hangs together as a tapestry of one harmonious piece. Not only can it be clearly seen why Bergson opposes Kant and the positivists so vehemently, but it can also be understood why he eventually set his sights upon The two sources of morality and religion. In the eyes of many critics this work, far from completing a natural progression of thought, stands outside the main body of work as something ill-fitting and almost cavalier. This thesis attempts to redress the balance by demonstrating how the spiritual and religious interpretation of life is central to Bergson's thought. Having established this, I have assumed it likely that a lively Catholic interest in Bergson is something quite logical and natural. This proved to be the case. After all, the Catholics in France stood to gain or lose most by the introduction in intellectural circles of a new philosophical 'spiritualism'. They would obviously themselves have a vested interest in the discrediting of materialist and positivist philosophies. However, scholars have not seen the connection between Bergson and Christian thought very clearly and no detailed research into this particular field has been undertaken. I have consequently attempted to review both the general field of Catholic reactions in a largely chronological way and also the detailed ways in which Bergson's thought had on impact upon Catholic writers. My main conclusion from this research is that Bergson's work lent itself to adaptation and alteration to something more orthodox in Catholic terms. However it was some time before it was viewed in a favourable enough light for anything like this to be attempted. Much prejudice and misinterpretation surrounded Bergson for some years. Eventually, however, his theories made deep inroads into the mainstream of Catholic thought. His theories of perception and intuition, of movement and change, of static and dynamic religion, helped bring about a significant change in the development of twentieth century religious thought.

Made available in DSpace on 2014-06-11T19:25:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-25Bitstream added on 2014-06-13T20:13:50Z : No. of bitstreams: 1 rosa_fs_me_botib.pdf: 208583 bytes, checksum: 815e421ed7e171ad3f2ddc3c714c6710 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The protocol called P-36 has been broad/y used to induce multiple ovulations, due to the fact that it allows fixed-time artificial insemination (FTAI), and facilitates embryo donors handling. Recent studies with P-36 protocol, have shownthat replacement of the last two doses of FSH by eCG improves embryo yield. However, after consecutive use, eCG may induce antibody and decrease bovine embryo production. The objective of the present study is to verify the efficiency of protocol P-36/eCG in Angus breed, and to test the replacement of eCG by LH in the last day of superestimulatory treatment. In experiment 1, 22 Angus cows were randomly allotted to 4 groups: LH60 (Control), LH60/eCG, LH60/LH and LH60/FSH+LH. Each donor was superovulated 3 times, in such a way that each animal received 3 of 4 treatments, totaling 17 cows in the first two groups and 16 in the others (incomplete block design). At a random stage of the estrous cycle (DO), the embryo donors received an intravaginal device (lVO) containing 1.0 9 of progesterone and estradiol benzoate (3.0 mg, i.m.). In the control group the animais were superestimulated with pFSH (i.m., total dose = 200 mg) twice a day in decreasing doses from 04 to 7, whereas in groups LH60/eCG and LH60/LH the last two doses of FSH were replaced by eCG (i.m, total dose = 400 lU) or LH (i.m., total dose = 2.0 mg), respectively. Finally, the cows trom group LH60/FSH+LH received two doses of 1.0 mg of LH simultaneously with the last two doses of FSH. Ali animais were treated with dc1oprostenol (150 mg, i.m.) on day 6, and the IVD was removed 36 h after PGF2a administration. Ovulation was induced with 12.5 mg of pLH (i.m.), on day 8, and the animais were FTAI 12 and 24 h after pLH. In experiment 2, 17 cows were randomly allocated in 3 groups: LH48, LH60 and LH48/FSH+LH. The difference between the first and the second experiment is that in groups LH48 and LH48/FSH+LH ... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:26:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-03Bitstream added on 2014-06-13T19:12:57Z : No. of bitstreams: 1 zuin_rg_me_jabo.pdf: 216391 bytes, checksum: a0e1c4fd33e27c06f5e9cb650e3c402f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Características de carcaça preditas por ultrassonografia foram incluídas nos programas de avaliação genética, uma vez que estas estão associadas à qualidade e rendimento de carcaça. Neste trabalho, os objetivos foram estimar os parâmetros genéticos e as tendências genéticas para área de olho de lombo (AOL), espessura de gordura subcutânea (EG) e espessura de gordura subcutânea de garupa (EGP8), peso corporal aos 210 (P210) e aos 365 (P365) dias de idade em bovinos da raça Nelore. Foram analisados dados de animais nascidos entre 1998 e 2008, oriundos de fazendas participantes do Programa de Melhoramento Genético da Raça Nelore (Nelore Brasil). As estimativas dos componentes de (co) variância, dos parâmetros genéticos e valores genéticos para as características estudadas foram obtidas pelo método da máxima verossimilhança restrita, sob modelo animal multi-característica. Para as características de peso as estimativas de herdabilidade genética direta e materna foram: 0,26 ± 0,003 e 0,18 ± 0,01, para P210 e 0,39 ± 0,02 e 0,05 ± 0,01, para P365. As estimativas de herdabilidade para AOL, EG e EGP8 foram iguais a 0,28 ± 0,03; 0,21 ± 0,02; 0,25 ± 0,03, respectivamente. Mudanças significativas nos valores genéticos médios anuais das características de carcaça indicaram que estas estão sendo indiretamente influenciadas pelo índice de seleção aplicado para estes rebanhos / Carcass traits by ultrasound measurements were included in genetic evaluation programs because they are associated with carcass yield and quality. This study aimed to estimate genetic parameters and genetic trends for back fat thickness (BF), rump fat thickness (RF), rib-eye area (REA) and body weight at 210 (BW210) and 365 (BW365) days of age. It data from animals whose herds participating in the Nelore breeding program (Nelore Brasil) born between 1998 and 2008, were used. Genetic parameters, (co)variance components and breeding values were estimated for each trait, in multi traits analysis, using maximum restricted likelihood method. Heritability estimates were equal to 0.28 ± 0.03 (REA); 0.21 ± 0.02 (BF) and 0.05 ± 0.01 (RF). In the growth traits the direct and maternal heritability estimates were respectively 0.26 ± 0.003; 0.18 ± 0.01 for BW210 and 0.39 ± 0.021; 0.05 ± 0.010 for BW365. Significant changes in the annual breeding values indicated that the carcass traits are being indirectly influenced by the selection index

Made available in DSpace on 2016-06-02T20:20:37Z (GMT). No. of bitstreams: 1 6268.pdf: 2312191 bytes, checksum: f16c107fdc91ed439efa845247c55dc4 (MD5) Previous issue date: 2014-06-30 / Financiadora de Estudos e Projetos / This thesis has been divided into three chapters for better understanding of the experiments. The first chapter refers to a brief Literature Review, with the main concepts and justifications for this work. The second chapter discusses the strategy of positional and functional candidate genes for traits of feed efficiency in Nelore cattle, and the third chapter presents a genome-wide association study for feed efficiency traits in the same population. Feed efficiency is an important production trait in beef cattle production systems. The aim of this study was to identify genes/QTLs associated with feed efficiency traits in Nelore cattle genotypes using the Illumina BeadChip BovineHD (770K) of 593 Nelore steers. The traits analyzed were: average daily weight gain (ADG), dry matter intake (DMI), feed conversion (FC), feed efficiency (FE), residual feed intake (RFI), efficiency of maintenance (EM), efficiency gain (EG), partial efficiency of growth (PEG) and relative growth rate (RGR). The first strategy discussed in this work, using candidate genes, investigated the association of Neurogenic differentiaton 1 (NEUROD1), Kv channel interacting protein 4 (KCNIP4), and Vascular endothelial growth factor C (VEGFC) genes, with production traits in the same population. Our results are in according to literature that indicate NEUROD1, KCNIP4 and VEGFC as candidate genes for feed efficiency; and this study is the first to suggest the NEUROD1 gene as a candidate for gene backfat thickness, body weigth and metabolic weight in Nelore cattle. In the genome-wide association study some QTL regions identified in this study minimally overlapped with QTL regions previously reported for feed efficiency in Bos Taurus cattle, and harbor genes with biological functions related to metabolic processes, lipid and protein metabolism, energy generation and growth. A comparison with published results indicates that different QTL and genes may be involved in the control of feed efficiency in this population of Nelore cattle. The validation of the results obtained in this work in independent populations may contribute to elucidation of the mechanisms will involved in the variation of feed consumption and specific improvement in Nelore programs. / Esta tese foi dividida em três capítulos para melhor compreensão dos experimentos realizados. O primeiro capítulo refere-se a uma breve Revisão de Literatura, com os principais conceitos e justificativas para a realização deste trabalho. O segundo capítulo aborda a estratégia de genes candidatos posicionais e funcionais para características de eficiência alimentar na raça Nelore e o terceiro capítulo apresenta um estudo de associação genômica ampla para características de eficiência alimentar na mesma população. A eficiência alimentar é uma característica produtiva importante em sistemas de produção de bovinos de corte. O objetivo deste estudo foi identificar genes/QTLs associados com características de eficiência alimentar em bovinos da raça Nelore utilizando genótipos do Illumina BovineHD BeadChip (770K). As características analisadas foram: ganho de peso médio diário (GMD), consumo de matéria seca (CMS), conversão alimentar (CA), eficiência alimentar (EA), consumo alimentar residual (CAR), eficiência da mantença (EM), eficiência de ganho (EG), eficiência parcial de crescimento (EPC) e taxa de crescimento relativo (TCR). A primeira estratégia abordada neste trabalho, a de genes candidatos, investigou a associação dos genes Neurogenic differentiaton 1 (NEUROD1), Kv channel interacting protein 4 (KCNIP4), e Vascular endothelial growth factor C (VEGFC), com características produtivas nesta mesma população. Nossos resultados corroboram com resultados da literatura que indicam os genes KCNIP4 e VEGFC como genes candidatos para eficiência alimentar; e este estudo é o primeiro a sugerir o gene NEUROD1 como gene candidato para espessura de gordura subcutânea, peso médio e peso metabólico em bovinos da raça Nelore. No estudo de associação genômica, algumas regiões de QTL identificadas foram sobrepostas minimamente com regiões de QTL relatadas anteriormente para eficiência alimentar em bovinos Bos taurus, e abrigam genes com funções biológicas relacionadas com processos metabólicos, metabolismo lipídico e proteíco, geração de energia e crescimento. A comparação com os resultados publicados indicam que diferentes QTL e genes podem estar envolvidos no controle da eficiência alimentar nesta população de bovinos da raça Nelore. A validação dos resultados obtidos neste trabalho em populações independentes pode contribuir para elucidação dos mecanimos envolvidos na variação do consumo alimentar e para programas de melhoramento específicos para a raça Nelore.

Made available in DSpace on 2016-06-02T20:21:23Z (GMT). No. of bitstreams: 1 2863.pdf: 780094 bytes, checksum: c8a008a959e5b4d1e7d94595428c3b47 (MD5) Previous issue date: 2010-02-22 / Universidade Federal de Minas Gerais / To remain competitive in the market of meat production, it is crucial that the Brazilian producer is aware of the criteria used by consumers for local and international markets. One factor that determines the beef quality is genetics, so it is necessary to conduct studies in Brazil to understand the genetic variation of carcass and meat quality traits in order to outline plans to improve such attributes. Backfat thickness (BFT) and ribeye area (RAE) are characteristics of late measurements, so the investigation of molecular markers associated with these characteristics can help in their inclusion in breeding programs. In cattle, some polymorphisms have been related to characteristics of meat production. Thus, this work aimed to assess the presence of polymorphisms in candidate genes PPARGC1A (peroxisome proliferative active recptor gamma coactivator 1A), FABP4 (fatty acid binding protein 4), DDEF1 (development and differentiation enhancing factor 1), Leptin, PSMC1 (proteasome 26S subunit, ATPase, 1) and IGF-1 (insulin-like growth factors) and associate them with production traits in reference families of Nellore breed. We used 280 steers descendants of 20 sires, that were chosen to represent the variability in Nellore. The sires were genotyped for all markers to investigate their allelic distribution within the race. The SNPs of the leptin and PSMC1 genes showed no variability in the bulls, so these were not genotyped in the progeny. The other markers were genotyped for the whole population. The investigation of the effects of markers on the characteristics was performed using a mixed model, including fixed and random effects, using the restricted maximum likelihood method. There was a significant association (P<0,05) between FABP4 and BFT and a suggestive association (P<0,10) between fat gain in the feedlot and these marker. Significant association was found between RAE, weaning weight (WW) and yearling weight (YW) and the DDEF1 gene and a suggestive association between the IGF-1 gene and YW in this sample of Nellore cattle. / Para que a produção de carne se mantenha competitiva no mercado, é fundamental que o produtor brasileiro esteja atento aos critérios requeridos pelos consumidores dos mercados locais e internacionais. Um dos fatores que determina a qualidade da carne bovina é a genética, sendo, portanto necessário conduzir estudos no Brasil relacionados à variação genética de características que influenciam a qualidade da carcaça e da carne bovina para que se possam delinear programas de melhoramento no sentido de aperfeiçoar tais atributos. A espessura de gordura subcutânea (EGS) e a área de olho de lombo (AOL) são características de mensuração tardia, por isso, a investigação de marcadores moleculares associados com essas características pode ajudar na inclusão das mesmas em programas de melhoramento. Em bovinos, alguns polimorfismos já foram relacionados com características de produção de carne. Assim, este trabalho teve como objetivo avaliar a presença de polimorfismos nos genes candidatos PPARGC1A (peroxisome proliferative active recptor gamma coactivator 1A), FABP4 (fatty acid binding protein 4), DDEF1 (development and differentiation enhancing factor 1 ), Leptina, PSMC1 (proteasome 26S subunit, ATPase, 1) e IGF-1 (insulin-like growth factor) e associálos com características de produção de carne em famílias de referência da raça Nelore. Foram utilizados 270 novilhos machos, descendentes de 20 touros, escolhidos para representar a variabilidade dentro da raça Nelore. Os touros foram genotipados para todos marcadores para investigar a distribuição alélica dentro da raça. Os SNPs dos genes Leptina e PSMC1 apresentaram-se fixados na amostra, sendo assim, estes não foram genotipados na progênie, enquanto os demais marcadores foram genotipados para toda população. A investigação dos efeitos dos marcadores sobre as características foi realizada através de um modelo misto, incluindo efeitos fixos e aleatórios, utilizando o método de máxima verossimilhança restrita. Foi encontrada uma associação significativa (P<0,05) entre o marcador FABP4 e EGS e associação sugestiva (P<0,10) entre ganho de gordura no confinamento e este marcador. Foi encontrada associação significativa entre o polimorfismo no gene DDEF1 e AOL, peso à desmama (PD) e peso ao sobreano (PS) e associação sugestiva entre o polimorfismo do gene IGF-1 e PS em bovinos da raça Nelore.