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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.
271

Perfil metabólico de cabras submetidas a transporte rodoviário / Metabolic profile of goats submitted to road transportation

Vanessa Martins Storillo 05 September 2012 (has links)
O transporte leva os animais ao estresse, que pode comprometer a saúde e bem estar destes, além de elevar a geração de substâncias reativas, aumentando a necessidade de antioxidantes. A idade também influencia o metabolismo, pois o envelhecimento causa modificações no organismo, levando a prejuízos funcionais. O objetivo deste estudo foi avaliar a influência do transporte rodoviário e da idade em cabras, tratadas ou não vitaminas A, D, e E. Foram utilizadas 20 cabras, da raça Boer, com cerca de 60 dias pós-parto, hígidas, manejo e dietas idênticos, de duas faixas etárias (de 1 até 4 anos de idade e entre 4 e 7 anos) e distribuídas em grupos de 10 animais. O transporte rodoviário teve duração de 4h. O exame físico e as coletas de sangue foram efetuados nos tempos T0 (-15d); T1 (-8d); T2 (-3d); T3 (0h); T4 (4h); T5 (5h); T6 (7h) e T7 (6d) do transporte. Em T1 e T2, 10 cabras receberam, via IM, 2mL de complexo com vitaminas A, D e E e 10 receberam solução fisiológica. Foram determinadas temperatura retal (TR); peso vivo (PV); escore de condição corporal (ECC); lactato L; ácidos graxos não esterificados (AGNEs); beta hidroxibutirato (BHB); ureia; creatinina; proteína total (PT); albumina; globulina; creatina fosfoquinase (cK); AST; GGT; glicose; eritrograma; concentrações eritrocitárias da superóxido dismutase (SOD) e o status antioxidante total (TAS). As variáveis PT, albumina, globulina, PV, ECC, AGNEs, AST, GGT, creatinina, ureia e eritrograma não se alteraram. O transporte diminuiu o BHB, não interferiu no TAS, mas em T4, as cabras mais jovens apresentaram menor TAS do que as com mais de 4 anos. A SOD não foi influenciada por transporte ou tratamento, sua concentração foi maior nas cabras jovens, e, nestas, quanto maior o ECC, menor a concentração de SOD. O estresse foi maior nas cabras de 1 a 4 anos. O transporte rodoviário de caprinos, mesmo de curta duração, causou estresse, verificado pelo aumento da glicemia, TR e lactato, independente da administração das vitaminas A, D e E, porém estas evitaram o aumento da cK, evidente nos grupos controles. / Animal transportation can trigger stress. Stress could compromise health and livestock welfare, as well increases the generation of reactive substances and raise the need for antioxidants. Age also affect the metabolism, because aging causes organic modifications that lead to functional impairment. The aim of this study was to analyze the influence of short road transportation and age in goats, treated or not, with vitamins A, D and E. It were used 20 healthy female Boer goats, calved two months ago, with identical diet and management, divided in groups by age (1 to 4 years of age and 4 to 7 years) and distributed in groups of 10 animals. The transportation lasted 4 hours. Physical examination and blood collection were performed in times T0 (-15d); T1 (-8d); T2 (-3d); T3 (0h); T4 (4h); T5 (5h); T6 (7h) and T7 (6d) from transportation. In T1 and T2, 10 goats received, by intramuscular injection, 2 mL of complex with vitamins A, D and E and 10 animals received saline solution. It were collected the followings parameters: rectal temperature (RT); body weight (BW), body condition score (BCS); non esterified fatty acids (NEFA); β hydroxybutyrate (BHB); lactate L; urea; creatinine; total protein (TP); albumin; globulin; creatine phosphokinase (cK); AST; GGT; glucose; erithrogram; erythrocyte concentrations of superoxide dismutase (SOD) and total antioxidant status (TAS). There were no differences for the parameters TP, albumin, globulin, BW, BCS, NEFA, AST, GGT, creatinine, urea and erithrogram. The transportation decreased BHB, and it had shown no influence on TAS, but in T4, the younger goats had lower TAS than older ones. SOD was not affected by transport or treatment, but show greater concentration in young goats, and, only in this category, higher ECC leads to lower SOD. The stress was higher in 1 to 4 years goats. Road transportation of goats, even in appropriate conditions, trigger stress, verified by elevated blood glucose, lactate and RT, regardless of the administration of vitamins A, D and E, but they prevented the increase of cK, evident in the control groups.
272

Ação preventiva de fármacos antiácidos e potenciais biomarcadores para úlcera abomasal decorrente do uso de fenilbutazona em ovinos adultos / Preventive action of antacid drugs and potential biomarkers for abomasal ulcer due to phenylbutazone use in adult sheep

Aline Alberti Morgado 29 January 2018 (has links)
Úlceras abomasais acarretam diminuição do bem-estar e da produção de leite e carne, porém informações quanto a sua etiopatogenia, diagnóstico, prevenção e tratamento ainda são insuficientes, em especial quando acometem ruminantes adultos. Os protocolos utilizados para prevenção e tratamento desta enfermidade são extrapolados dos determinados para a lesão estomacal em monogástricos, havendo ainda incertezas sobre o efeito dos princípios ativos, doses e vias de administração mais adequados para ruminantes. Com o intuito de testar a capacidade da ranitidina e do omeprazol prevenirem o aparecimento de úlcera abomasal realizou-se administração dos antiácidos concomitantemente ao uso de fenilbutazona por sete dias (4,4 mg/kg, duas vezes ao dia, pela via intravenosa). Oito ovinos hígidos e canulados em abomaso foram distribuídos em dois quadrados latinos 4x4 e tratados com 2 mg de ranitidina/kg de peso vivo, pela via intravenosa, a cada doze horas; 0,4 mg/kg de omeprazol, pela via intravenosa, uma vez ao dia; 4 mg/kg de omeprazol em pasta, via oral, uma vez ao dia; ou nenhum medicamento antiácido (controle). Omeprazol administrado pela via intravenosa desencadeou flebite e maior número de animais apresentou lesões na mucosa abomasal. Omeprazol em pasta não foi eficaz na prevenção de úlcera do tipo 1a. Embora sem diferença entre os grupos, a ranitidina revelou o menor número de animais com lesões confirmadas pelo exame histológico; no entanto, este antagonista H2 ocasionou aumento da frequência cardíaca. O pH e a acidez do conteúdo abomasal, as concentrações séricas do pepsinogênio e da lisozima, bem como a pesquisa de sangue oculto fecal não se mostraram válidos para o diagnóstico da úlcera de abomaso do tipo 1a em ovinos adultos. / Abomasal ulcers reduce welfare and production of milk and meat, but information about their etiopathogenesis, diagnosis, prevention and treatment is still insufficient, especially for adult ruminants. Protocols used for prevention and treatment of this disease are extrapolated from those determined for gastric lesions in monogastric animals. However, there are still uncertainties about the preventive effect of these drugs, the used doses and best route of administration to ruminants. The preventive action of ranitidine and omeprazole on the development of abomasal ulcers was tested. The antacid drugs were administered concomitantly to phenylbutazone over seven days (4.4 mg/kg twice a day, intravenously). Eight healthy sheep, cannulated in abomasum, were distributed in two 4x4 Latin squares and treated with 2 mg/kg of ranitidine every 12 hours; 0.4 mg/kg of omeprazole, administered intravenously once a day; 4 mg/kg of omeprazole paste, administered orally once a day; or no antacid drug (control). Intravenously administered omeprazole caused phlebitis and a higher number of animals had lesions in the abomasal mucosa. Omeprazole paste was not effective in the prevention of type 1a ulcer. Although there was no difference between groups, ranitidine showed the lowest number of animals with lesions diagnosed by histological examination; however, this H2 antagonist caused an increase in heart rate. Measurements of pH and acidity of abomasal contents, serum pepsinogen and lysozyme concentrations, as well as fecal occult blood screening were concluded not to be valid biomarkers for type 1a abomasal ulcers in adult sheep.
273

Chlordécone et filières animales antillaises : de la distribution tissulaire aux stratégies de décontamination chez les ruminants / Chlordecone and livestock in the French West Indies : From the tissue distribution to the decontamination strategies in ruminants

Lastel, Marie-Laure 16 December 2015 (has links)
La CLD est un composé toxique qui (i) pollue plus de 15% des surfaces agricoles de la Guadeloupe et de la Martinique, (ii) résiste à la dégradation biotique et abiotique, (iii) s’accumule le long de la chaine alimentaire et dont la disparition des sols par lessivage est estimée à plusieurs centaines d’années. Les animaux de rente originaires de ces zones polluées sont contaminés et l’état de l’art a révélé un manque d’information évident sur le comportement de la CLD dans l’organisme de ces animaux et moins de dix publications sur leur décontamination. Deux protocoles expérimentaux ont été conduits sur des caprins mâles en croissance afin de caractériser le comportement de la CLD dans l’organisme des ruminants non lactants et de développer des méthodes optimisant leurs processus de décontamination. Les résultats ont montré que (i) les chevreaux éliminaient plus de 70% de leur CLD tissulaire après 3 à 4 semaines de décontamination et (ii) ni leur état d’engraissement initial ni l’ajout de charbon actif ou d’huile de paraffine dans leur alimentation ne modifiaient ces taux d’excrétion. Ces études ont également montré que la CLD se comportait différemment des autres polluants lipophiles car sa concentration tissulaire (exprimée sur la base de la matière grasse) était plus importante dans le foie et les muscles des animaux contaminés que dans leurs tissus gras. Ces résultats soulèvent des questions sur les mécanismes à l'origine de la distribution tissulaire de la CLD, son métabolisme et sur l’interaction de ce dernier avec le cycle entéro-hépatique. La compréhension de ces processus permettra de mieux ajuster les stratégies de décontamination pour les rendre plus efficaces / Chlordecone (CLD) is a toxic molecule which (i) contaminates more than 15% of agricultural land in Guadeloupe and Martinique islands, (ii) resists to biotic and abiotic degradation, (iii) accumulates along the food chain and whose the disappearance by soil leaching is estimated at several hundred years. The contamination of livestock in polluted areas is a health, social and economic issue. A literature review on CLD revealed a crying lack of information on its behavior in livestock’s organism and currently, there are less than ten studies which deal with livestock’s decontamination. Two experimental protocols were developed to characterize the behavior of CLD in ruminants’ organism and to evaluate methods that can optimize the decontamination processes of these animals. Results showed that all animals have eliminated more than 70% of Chlordecone in 3 to 4 weeks and neither the initial kids’ body fatness nor the addition of activated carbon or the addition of paraffin oil in the diet during the decontamination period altered these rates of excretion. Following these studies, the lipophilic behavior of CLD in animals is, also, questioned because the results showed that the concentrations of this pollutant, expressed on the fat matter basis, were higher in the liver and the muscles than in the peri-renal fat. These results raised new questions: firstly, on the mechanisms which control the CLD tissue distribution and secondly, on the role of the CLD metabolism and its interaction with the entero-hepatic cycle. The understanding of these processes should help to better adjust the decontamination strategies in order to make them more efficient
274

The effect of glycosylation on the stability of exogenous xylanase under in vitro proteolytic conditions similar to the rumen

Van de Vyver, Wilhelmus Francois Joubert 10 August 2005 (has links)
The aim of this study was to evaluate the effect of glycosylation on exogenous xylanase stability when incubated under proteolytic conditions. Xylanase produced by Trichoderma longibrachiatum, was purified using gel filtration chromatography, ammonium sulfate salt precipitation and dialysis. A partially purified xylanase with Mr of 20- and 10 kDa was identified and contained >65% of the original xylanase activity. Glycoproteins present in the xylanase were identified by thymol sulfuric acid staining or by the FITC-Iabeled lectin method, specific for glycoproteins. This naturally glycosylated xylanase was enzymatically deglycosylated with one of two endo-N-glycosidases: PNGase F or Endo H. Efficiency of deglycosylation was determined with electrophoresis by observing protein mobility shifts or by staining with FITC-Iabeled lectin. The effect of glycosylation on the stability of the exogenous xylanase was tested by incubating the glycosylated or deglycosylated xylanase with rumen fluid (Rf), Prevotella ruminicola culture supernatant (Pr) or a commercial protease from Bacillus subtilis (Bs) for 0, 3, 6, 9 and 24h at 37°C. Results indicated that glycosylated xylanase was significantly more stable (P<0.05) against proteolytic inactivation under the relatively low protease conditions of Rf and Pr (0.018 and 0.046 mg azocasein degraded/ml/h, respectively), but not under high proteolytic conditions of Bs (1.009 mg azocasein/mllh). Also, the glycosylation effect was observed earlier when incubated with the numerous proteases of Rf (3h), than with Pr (9h). These results indicate that glycosylation enhances xylanase stability and therefore is an important characteristic for exogenous enzyme supplements for ruminants. / Dissertation (MSc (Agric))--University of Pretoria, 2005. / Animal and Wildlife Sciences / unrestricted
275

Digestibilidade de Nutrientes em Dietas com Fubá de Milho e Resíduo de Pastifício, em ovinos / Nutrient digestibility in diets with ground corn and pasta residue, in sheeps

Azevedo, Marcello Machado de 26 October 2011 (has links)
Made available in DSpace on 2016-05-02T13:55:31Z (GMT). No. of bitstreams: 1 MarcelloMachado Azevedo-dissertacaocompleta.pdf: 158470 bytes, checksum: b5f588f1ea17f6cde44c72dd2b1f3588 (MD5) Previous issue date: 2011-10-26 / The objective was to analyze the apparent digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and ethereal extract (EE) of different doses of the pasta residue in the nutrition of sheeps replacing corn bran. The animals were not castrated males, mixed breed, aged approximately six months, average weight of 30.0 ± 3.0 kg. There were six treatments with four replications (24 plots) : S = 100% corn silage, 40s/60c = 40% corn silage + 60% ground corn, 40s/60r = 40% corn silage + 60% residue, 40s/45c/15r = 40% corn silage + 45% ground corn + 15% residue, 40s/30c/30r = 40% corn silage + 30% ground corn + 30% residue, and 40s/15c/45r = 40% corn silage + 15% ground corn + 45% residue. The treatment with higher dose of residue showed higher digestibility of DM (40s/15c/45r = 89,93%; 40s/60r = 90,71%), OM (40s/15c/45r = 89,31%; 40s/60r = 89,57%) and CP (40s/15c/45r = 58,01%; 40s/60r = 59,96%). The NDF had a higher digestibility only at treatment composed just with the residue (40s/60r = 60,51%). The ADF had, in all the treatments that included residue, increased the fiber digestibility. For the EE, differences of digestibility were not observed between the treatments using concentrated. The inclusion of pasta residue replacing the corn bran is recommended in diets for sheeps. / Objetivou-se, com esta pesquisa, analisar a digestibilidade aparente da Matéria Seca (MS), da Matéria Orgânica (MO), Proteína Bruta (PB), Fibra em Detergente Neutro (FDN), Fibra em Detergente Ácido (FDA) e Extrato Etéreo (EE) de diferentes doses do resíduo oriundo de pastifício na nutrição de ovinos em substituição ao farelo de milho. Utilisaram-se machos inteiros, sem raça definida, previamente everminados, com idade aproximada de seis meses, peso médio de 30,0 ± 3,0 kg. Foram seis tratamentos com quatro repetições (24 parcelas experimentais): S = 100 % de silagem de milho; 40s/60m = 40% de silagem de milho + 60% de milho moído; 40s/60r = 40% de silagem de milho + 60% de resíduo de pastifício; 40s/45m/15r = 40% de silagem de milho + 45% de milho moído + 15% de resíduo de pastifício; 40s/30m/30r = 40% de silagem de milho + 30% de milho moído + 30% de resíduo de pastifício; e 40s/15m/45r = 40% de silagem de milho + 15% de milho moído + 45% de resíduo de pastifício. O modelo experimental foi o Delineamento Inteiramente Casualizado (DIC) sendo os resultados submetidos ao teste de Scott-Knott, com 5% de significância (programa SISVAR®). Os tratamentos com maiores doses de resíduo demonstraram maior digestibilidade média da MS (40s/15m/45r = 89,93%; 40s/60r = 90,71%), MO (40s/15m/45r = 89,31%; 40s/60r = 89,57%) e PB (40s/15m/45r = 58,01%; 40s/60r = 59,96%). A FDN apresentou maior digestibilidade apenas no tratamento exclusivo com resíduo de pastifício no concentrado (40s/60r = 60,51%). Quanto à FDA, todos os tratamentos que tiveram inclusão de resíduo de pastifício aumentaram a digestibilidade da fibra, independente da dosagem de farelo de milho. Para o EE, nenhum tratamento utilizando concentrado diferiu quanto à digestibilidade. A inclusão de resíduo de pastifício em substituição ao farelo de milho é recomendada na alimentação de ovinos.
276

Efeitos da enramicina ou da monensina sódica sobre a fermentação ruminal e a digestão total em bovinos / Effects of enramycin or sodium monensin on ruminal fermentation and on total digestibility in bovine

Borges, Luiz Felipe de Onofre 18 May 2006 (has links)
Foram objetivos do presente experimento estudar os efeitos da administração da enramicina, em comparação com a monensina sódica, sobre a fermentação ruminal e a digestibilidade total em bovinos. Doze fêmeas bovinas não-gestantes e não-lactantes (675 kg ± 63 de PV) foram distribuídas inteiramente ao acaso aos três tratamentos formados por um grupo controle (ausência de antibiótico), um grupo tratado com enramicina (antibiótico não-ionóforo) e outro tratado com monensina (antibiótico ionóforo). A enramicina foi administrada na dose de 20 mg/animal/dia e a monensina na dose de 300 mg/animal/dia. O experimento teve duração total de 21 dias, sendo os 10 últimos destinados à aplicação do marcador (15 g de óxido crômico/animal/dia) e os últimos 5 dias destinados à coleta de fezes e amostragem dos alimentos. O 21º dia foi utilizado para colheitas de líquido ruminal realizadas às 0, 2, 4, 6, 8, 10 e 12 horas após a 1a refeição para determinação dos AGVs, pH e nitrogênio amoniacal. A monensina aumentou a concentração total de AGVs no tempo 12 horas após a alimentação e diminuiu a relação acético:propiônico nos tempo 0 e 6 h, em relação à enramicina, mas não em relação ao controle. Nenhum dos antibióticos testados alterou a proporção molar dos ácidos acético, propiônico e butírico, bem como o pH ou a concentração ruminal de nitrogênio amoniacal. Também não alterou o comportamento de consumo, avaliado em atividades de alimentação, ruminação e ócio. Nenhum dos antibióticos testados alterou a digestibilidade da matéria seca, proteína bruta, extrato etéreo, extrativo não nitrogenado, fibra bruta, fibra em detergente ácido, fibra em detergente neutro, amido, energia bruta ou os nutrientes digestíveis totais / The objective of this trial was to study the effects of enramycin administration, compared to sodium monensin, on ruminal fermentation and on total digestibility of diet nutrients in bovine. Twelve non-pregnant and non-lactating cows (675 ± 63 kg of BW) were randomly assigned to three treatments: control group (non-antibiotic), enramycin-treated group (non-ionophore antibiotic) and monensin-treated group (ionophore antibiotic). Treatments were 20 mg/animal/day of enramycin or 300 mg/animal/day of monensin. Trial lasted 21 days, the last 10 used for external marker administration (15 g of chromic oxide/animal/day) and the last 5 for feces collection and feed sampling. The 21st day was used for ruminal fluid sampling at 0, 2, 4, 6, 8, 10 and 12 hours after 1st meal to determine VFA, pH and ammoniacal nitrogen. Monensin increased total VFA concentration 12 h after feeding and decreased the acetic:propionic ratio at times 0 and 6 h, in relation to enramycin, but not when compared to control. The two antibiotics tested did not influence the molar proportion of acetic, propionic or butiric acids, pH, ammoniacal-N concentration, or dry matter intake and intake behavior, evaluated during activities of feeding, rumination and idleness. The two antibiotics tested did not alter the digestibility of dry matter, crude protein, ether extract, nitrogen-free extract, crude fiber, acid detergent fiber, neutral detergent fiber, starch, gross energy and total digestible nutrients (TDN), or the intake of digestible dry matter or TDN
277

Hemodinâmica e efeitos respiratórios e sedativos da associação de detomidina e nalbufina pela via intramuscular em ovinos /

Sousa, Élen Almeida Pedreira de. January 2019 (has links)
Orientador: Paulo Sergio Patto dos Santos / Resumo: Objetivou-se com este trabalho avaliar os efeitos na hemodinâmica, respiração, motilidade ruminal e sedação, da associação de detomidina e nalbufina em ovinos. Foram utilizados 8 ovinos hígidos, jovens, fêmeas ou machos, pesando 54,85 ± 20,31kg. Foi instalado na veia jugular esquerda um introdutor e, posteriormente, posicionado um cateter de Swan-Ganz com a extremidade distal alocada no lumen da artéria pulmonar. Foi administrado pela via intramuscular detomidina (10μg/kg) associado a nalbufina (0,1mg/kg). Foram avaliadas FC, PAS, PAD, PAM, PVC, PAPm, IC, IS, IRVS, FR, pH, PaO2, PaCO2, HCO3, TC, sedação e motilidade ruminal antes do início da administração dos fármacos (MB) e a cada quinze minutos após a aplicação durante sessenta minutos (M15, M30, M45 e M60). Houve redução do IC, FR e aumento da PAS, PAPm, temperatura central, PaCO2 e HCO3 após administração dos fármacos. A sedação foi considerada satisfatória durante 45 minutos. Com os resultados obtidos neste estudo, conclui-se que a neuroleptoanalgesia promovida pela associação de detomidina e nalbufina em ovinos, nas doses utilizadas, promove sedação satisfatória. As alterações hemodinâmicas, respiratórias e na motilidade ruminal observadas podem ser bem toleradas por animais sadios. / Abstract: The aim of this study was to evaluate the effects on hemodynamics, respiration, ruminal motility and sedation of the combination of detomidine and nalbuphine in sheep. Were used eight healthy young, female or male sheep, weighing 54.85 ± 20.31kg. A Percutaneous Sheath Introducer was placed in the left jugular vein and then a Swan-Ganz catheter was positioned with the distal port allocated to the lumen of the pulmonary artery. Association of detomidine (10µg/kg) and nalbuphine (0,1mg/kg) was administered intramuscular. HR, SAP, DAP, MAP, CVP, MPAP, CI, SI, SVRI, RR, pH, PaO2, PaCO2, HCO3, CT, sedation and ruminal motility before drug administration (MB) and at each fifteen minutes after application for sixty minutes (M15, M30, M45 and M60). There was a reduction in CI, RR and increase in SAP, mPAP, CT, PaCO2 and HCO3 after drug administration. Sedation was considered satisfactory for 45 minutes. The results of this study allowed us to conclude that neuroleptoanalgesia promoted by the association of detomidine and nalbuphine in sheep at the doses used, promotes satisfactory sedation for short procedures. The hemodynamic, respiratory and ruminal motility changes observed can be well tolerated by healthy animals. / Mestre
278

Etude des variants structuraux génomiques pour comprendre les processus démographiques et adaptatifs impliqués dans la domestication des petits ruminants / Genome structural variations to understand the adaptive anddemographic processes during domestication of small ruminants.

Cumer, Tristan 13 December 2017 (has links)
Les variants structuraux génomiques (SVs) composent une large part du polymorphisme observable entre les individus mais leurs impacts sur les processus micro-évolutifs restent mal connus et leur étude à large échelle est rare.La première partie de ce manuscrit est une étude de la bibliographie portant sur les SVs décrits chez les animaux domestiques. Cette partie met en avant l'importance des SVs dans la modification des gènes ou de leur régulation, impactant un grand nombre de traits sélectionnés lors de la domestication, en lien avec la productivité, la morphologie ou encore le comportement.Basée sur l’étude de données de reséquençage de 500 génomes complets de petits ruminants sauvages et domestiques, la seconde partie, ciblant trois SVs décrits dans la bibliographie, a permis (i) de réfuter l’hypothèse d’amplification en lien avec la domestication des copies endogènes protectrices du retrovirus JSRV situées dans la région 6q13 du mouton, (ii) d’identifier des duplications entourant et affectant le gène ASIP qui seraient impliquées dans les modifications de coloration du pelage en lien avec la domestication des petits ruminants, ainsi que (iii) de montrer un potentiel rôle adaptatif d'un haplotype du locus de la beta-globine lié au climat aride chez le mouton.La troisième partie se base sur une recherche sans a priori de l’ensemble des SVs présents dans des génomes complets. Au travers du développement d’une méthode de détection des SVs et de son application, cette partie permet de décrire environ 50k et 20k SVs dans les génomes des Ovis et des Capra. Parmi ces SVs, 135 chez Ovis et 70 chez Capra semblent liés à la domestication et affectent des gènes impliqués dans l’amélioration, l’immunité, la reproduction ou la survie. De plus, les distributions de 130 SVs pour les moutons et 35 SVs pour les chèvres covarient avec des variables environnementales au Maroc. Certains affectent des gènes impliqués dans la morphologie, l’immunité et le métabolisme.Ce travail met ainsi en avant de nombreux variants qui peuvent impacter des gènes et qui ont pu être ciblés lors la domestication initiale, des étapes d’amélioration ultérieure ou de l’adaptation locale des petits ruminants. Il démontre l'importance de prendre en compte les variants structuraux dans les études génomiques visant à décrire les bases génétiques de la domestication. / Genomic structural variations (SVs) account for a large part of the polymorphism between individuals, but their impacts on micro-evolutionary processes remain poorly known and large-scale studies are scarce.The first part of this manuscript is a bibliographic study of SVs in domestic animals. This part highlights the importance of SVs in modifying genes or their regulation, impacting a large number of traits selected during domestication and linked to productivity, morphology or behaviour.Based on the study of resequenced data from 500 whole genomes of wild and domestic small ruminants, the second part, targeting three SVs described in the bibliography, allowed (i) to refute the hypothesis of a link between the domestication of sheep and the amplification of endogenous protective copies of the JSRV retrovirus located in the 6q13 region, l, (ii) to identify duplications surrounding and affecting the ASIP gene that could be involved in the coat color changes related to the domestication of small ruminants, as well as (iii) highlight a potential adaptive role to arid climate of an haplotype of beta-globin locus in sheep.In the third part, we conducted a whole genome survey of SVs . Through the development of a SVs detection method and its application, we could detect about 50k and 20k SVs in Ovis and Capra. Of these SVs, 135 and 70 in Ovis and Capra, respectively, appear to be linked with domestication and affect genes involved in improvement, immunity, reproduction or survival. In addition, in Morocco, the distributions of 130 SVs for sheep and 35 SVs for goats covariate with environmental variables. Some of them affect genes involved in morphology, immunity and metabolism.This work highlights that many variants impacting genes might have been targeted during initial domestication and subsequent improvement steps or during the local adaptation of sheep and goats. It demonstrates the importance of considering structural variants in genomic studies to describe the genetic basis of domestication.
279

Estimation of energy expenditure of grazing ruminants via accelerometry / 加速度測定による放牧反芻家畜のエネルギー消費量推定

Miwa, Masafumi 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20433号 / 農博第2218号 / 新制||農||1048(附属図書館) / 学位論文||H29||N5054(農学部図書室) / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 廣岡 博之, 教授 久米 新一, 教授 今井 裕 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
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Paratuberculosis: The Hidden Killer of Small Ruminants

Idris, Sanaa M., Eltom, Kamal H., Okuni, Julius B., Ojok, Lonzy, Elmagzoub, Wisal A., Abd El Wahed, Ahmed, Eltayeb, ElSagad, Gameel, Ahmed A. 24 April 2023 (has links)
Paratuberculosis (PTB) is a contagious and chronic enteric disease of ruminants and many non-ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP), and is characterised by diarrhoea and progressive emaciation with consequent serious economic losses due to death, early culling, and reduced productivity. In addition, indirect economic losses may arise from trade restrictions. Besides being a production limiting disease, PTB is a potential zoonosis; MAP has been isolated from Crohn’s disease patients and was associated with other human diseases, such as rheumatoid arthritis, Hashimoto’s thyroiditis, Type 1 diabetes, and multiple sclerosis. Paratuberculosis in sheep and goats may be globally distributed though information on the prevalence and economic impact in many developing countries seem to be scanty. Goats are more susceptible to infection than sheep and both species are likely to develop the clinical disease. Ingestion of feed and water contaminated with faeces of MAP-positive animals is the common route of infection, which then spreads horizontally and vertically. In African countries, PTB has been described as a “neglected disease”, and in small ruminants, which support the livelihood of people in rural areas and poor communities, the disease was rarely reported. Prevention and control of small ruminants’ PTB is difficult because diagnostic assays demonstrate poor sensitivity early in the disease process, in addition to the difficulties in identifying subclinically infected animals. Further studies are needed to provide more insight on molecular epidemiology, transmission, and impact on other animals or humans, socio-economic aspects, prevention and control of small ruminant PTB.

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