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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.
201

Desempenho e caracteristicas da carcaÃa de caprinos mestiÃos anglo nubiano, boer e caprinos sem padrÃo racial definido em pastagem e em confinamento / Performance and characteristics of the carcass of goat mestizos nubiano anglian, to boer and goat without defined racial standard in pasture and confinement

Antonio Nunes de Oliveira 21 July 2006 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O objetivo da pesquisa foi avaliar o desempenho corporal e as caracterÃsticas de carcaÃa de cabritos mestiÃos oriundos do cruzamento de reprodutores das raÃas especializadas de carne Anglo nubiana e Boer com matrizes Sem PadrÃo Racial Definido â SRD, com diferentes graus de sangue e em diferentes sistemas de produÃÃo. O trabalho foi desenvolvido, durante 3 anos (2002 â 2004), na Fazenda Experimental Vale do Curu, pertencente à Universidade Federal do CearÃ-UFC. Foram avaliados um total de 207 caprinos de ambos os sexos correspondentes a 5 grupamentos genÃticos: 1/2 Anglo nubiana x  SRD,  Anglo nubiana x  SRD,  BÃer x SRD,  Boer x  SRD e caprinos Sem PadrÃo Racial Definido-SRD. No estudo foram executados trÃs experimentos, tendo o segundo duas observaÃÃes: Experimento 1- âDesenvolvimento corporal de caprinos mestiÃos Boer e Anglo nubiano e caprinos Sem PadrÃo Racial Definido na regiÃo se i-Ãrida do Nordesteâ. O experimento teve como objetivo avaliar o ganho de peso de cabritos de diferentes grupamentos genÃticos, do nascimento atà aos 270 dias de idade, mantidos em pastagens nativa nas condiÃÃes usuais de criaÃÃo do Nordeste. Os resultados mostraram que o ganho de peso dos cabritos foi similar entre os diferentes grupos genÃticos do nascimento atà os 270 dias de idade, porÃm o peso ao nascer dos cabritos mestiÃos foi superior aos SRD. Conclui-se que cabritos mestiÃos oriundos de reprodutores das raÃas especializadas para carne Anglo nubiana e Boer, quando mantidos em condiÃÃes de pastejo na caatinga do semi-Ãrido nordestino, nÃo apresentam superioridade no ganho de peso em relaÃÃo aos SRD. Experimento 2. âDesempenho em confinamento de caprinos mestiÃos Anglo nubiano e Boer com diferentes frequÃncias genÃticasâ . Foram avaliados caprinos, de ambos sexos, durante um perÃodo de 60 dias com dieta de alto valor energÃtico, constituÃda de 70% de concentrado e 30% de volumoso (feno de capim elefante e de leucena, em proporÃÃes iguais). Avaliou-se os ganhos de peso total e diÃrio, conversÃo alimentar e o consumo mÃdio diÃrio. Neste estudo foi avaliado inicialmente o desempenho de cabritos de graus de sangue  e  BÃer e Anglo nubiano, nÃo observando-se diferenÃas significativas entre os grupos estudados, embora observou-se uma superioridade no ganho de peso dos cabritos  BÃer. Num segundo estudo, foi comparado o desempenho dos cabritos mestiÃos  com os SRD. Os cabritos do grupo genÃtico  Anglo nubiano e  Boer, quando comparados aos SRD, nÃo apresentaram diferenÃas (P>0,05). Experimento 3. Efeito do genÃtipo e do peso de abate sobre as caracterÃsticas da carcaÃa de caprinos mestiÃos Anglo nubiano e Boer e Sem PadrÃo Racial Definido-SRD. No experimento foram estudadas as caracterÃsticas da carcaÃa de cabritos de trÃs grupos genÃticos:  Anglo nubiana,  Boer e SRD, abatidos, dentro de cada grupo, com trÃs diferentes pesos: 20, 25 e 30 kg. Avaliou-se as caracterÃsticas de rendimento e conformaÃÃo da carcaÃa, bem como as perdas por resfriamento, levando em consideraÃÃo os efeitos do genÃtipo, peso e idade de abate e suas interaÃÃes. Os resultados mostraram que nÃo houve interaÃÃo entre o genÃtipo e o peso de abate em todas as variÃveis estudadas. O genÃtipo teve efeito significativo (P<0,05) no rendimento e conformaÃÃo da carcaÃa, com os menores valores observados nos caprinos SRD, nÃo havendo diferenÃas significativas entre os caprinos mestiÃos Anglo nubiano e Boer. O peso de abate influenciou tambÃm significativamente (P<0,05) o rendimento e conformaÃÃo da carcaÃa, com os menores valores observados nos caprinos abatidos com 20 kg de peso vivo, nÃo observando-se diferenÃas entre os grupos abatidos com 25 e 30 kg de peso. Conclui-se que cabritos mestiÃos Anglo nubiana e Boer apresentam similaridade no rendimento e conformaÃÃo de carcaÃa em relaÃÃo aos SRD e que carcaÃas de cabritos abatidos acima de 25 kg de peso vivo apresentaram melhor rendimento e conformaÃÃo que as carcaÃas provenientes de animais abatidos com 20 kg / The objective was evaluate the growth rate of different genetic kids, from birth to 270 days of age, to determine the most appropriate genotype to produce goat meat in the Northeast region of Brazil. The experiment was conducted on Vale do Curu Experimental farm, (Federal University of CearÃ), state of CearÃ, Brazil. During a period of 3 years (2002 - 2004), were evaluated a total of 207 kids from both sex corresponding to five genetic groups:  Anglo nubian x  SRD,  Anglo nubian x  SRD,  Boer x  SRD,  Boer x  SRD and native kids (without definition breed) - SRD. Kids were kept with their mothers until weaning, with approximately 90 days of age. In experiment one, the animals were maintained on native pasture until of 98 ha, with mineral supplementation and concentrated ration, during the dry period, however the birth weight of crossbreed kids were higher than the SRD. In experiment two e tree, it was evaluated the growth rate performance of different crossbreed kids in feedlot to determine the genetic type more efficient to weight gain. The experiments was carried out in the Zootecnia Department of Federal University of CearÃ. Animals were maintained receiving in feedlot during a period of 60 days receiving a high energy diet, twice a day, constituted of 70% of concentrated and 30% of bulky (hay of grass elephant and of leucena). It was evaluated the total and daily weight gain, feed conversion, and the daily average consumption. The male kid goats presented highest numbers in the total and daily weight gain, feed conversion, and in the daily average consumption, compared to the female. In experiment three, the aim of this work was to study the carcass characteristics of crossbreed goats Anglo nubian, Boer and without defined breed-SRD slaughtered at different live weight. The goats were studied distributed in different genetic groups and three slaughter weights: 20, 25 and 30 kg of live weight, It was evaluated studies the yield and conformation carcass characteristics taking and comparing within groups of genotype and slaughter weight. Data were analyzed by the minimum squares method, using the procedure GLM (Lineal General Models) of SAS and means compare by Ât test. Yields and conformation of hot and cold carcass characteristics was significant superior (P <0.05) on  Boer and  Anglo nubian groups than SRD, with similar results for slaughter weight, both higher at 25 and 30 kg live weights than the group of 20 kg. It was concluded that crossbreed kids from Anglo nubian and Boer Bucks didnât show superiority on body gain weight compared to SRD when are raised on native pasture in the semi-arid of Northeast of Brazil and maintained in confinement, presented similarity in the earnings of daily weight gain (GMD), carcass characteristics in relation than SRD and superior higher than SRD and goats slaughtered over 25 kg of live weight showed better characteristics than goat slaughtered with 20 kg
202

Desenvolvimento reprodutivo de cabritas Saanen submetidas ao efeito macho no período peri-púbere / Reproductive development in Saanen goat kids subject to the male effect during the peri-pubertal period

Laurinda Augusto 06 April 2015 (has links)
O efeito macho, principal fator social associado a reprodução, é muito usado na estimulação da atividade cíclica durante o anestro em espécies sazonais. Há também referência da sua influência sobre a puberdade podendo acelerar idade em que esta ocorre, particularmente em suínos e ratos. O presente projeto tinha como objetivo estudar o efeito da exposição de cabritas Saanen peri-púbere ao efeito macho sobre o desenvolvimento reprodutivo em particular no padrão de comportamentos associados ao cio, perfil de estrógeno e progesterona e na expressão do gene kiss1, receptores de kisspeptinas, estrógeno e progesterona no hipotálamo, hipófise e ovário. No experimento 1, 29 cabritas Saanen entre 142,72 &plusmn; 10,61 dias idade e 24,9 &plusmn; 4,26 kg de peso, foram distribuídas aleatoriamente entre três tratamentos: 1) exposição ao macho sexualmente ativo (grupo macho); 2) exposição a fêmea androgenizada (grupo fêmea) e; 3) controle (grupo controle). Observação diária de comportamentos associados ao cio e coletas de sangue para determinação dos níveis de estradiol e progesterona foram realizadas de maio a outubro. Os grupos macho e fêmea registraram mais comportamentos associados ao cio que os animais do grupo controle. A interação social teve efeito sobre a posição da cauda, aspecto da vulva, vocalizar e deixar montar. Houve diferenças significativas entre os grupos nas médias de estradiol. O grupo macho registrou médias de estradiol superiores ao grupo controle. Houve interação grupo*coleta no perfil de progesterona. Os grupos macho e fêmea registraram médias significativamente mais altas comparado ao grupo controle durante o experimento. No experimento 2, 16 cabritas Saanen com 138,37 &plusmn; 3,59 dias de idade e 22,75 &plusmn; 2,43 kg de peso foram distribuídas aleatoriamente entre dois tratamentos: 1) exposição ao macho sexualmente ativo (grupo macho) e; 2) controle (grupo controle). Foram realizadas observações diárias de comportamentos associados ao cio, coletas de sangue duas vezes por semana para determinação dos níveis de estradiol e progesterona e coleta de tecidos hipotalâmico, hipofisário e ovárico (antes e 60 dias depois da exposição ao macho) para determinar a expressão do gene kiss1, receptores de kisspeptinas, estradiol e progesterona. Não houve diferença entre grupos no comportamento deixar montar. O grupo macho registrou maior frequência de comportamento montar, contudo o grupo fêmea registrou maior frequência na alteração do aspecto da vulva, deslocar e interagir. Foram encontradas diferenças significativas entre grupos para perfil de progesterona, a expressão de kiss1, kiss1R, ER&alpha;, ER&beta; e PR no hipotálamo, expressão de ER&alpha; na hipófise e ER&alpha;, ER&beta; e PR no ovário. Em conjunto, os resultados encontrados indicam que o nível de expressão de mRNA das moléculas estudas varia entre animais sexualmente imaturos e maduros e é influenciado pela fase de desenvolvimento folicular em animais pós-pubere. / Male effect, major social factor associated to reproduction, is mainly used to stimulate cyclic activity during anestrus period in seasonal breeder species. There are references to the influence of male effect on puberty where it can advance the age at which puberty occurs. The present project aimed to study the effect of exposure of peri-pubertal Saanen goat kids to the male effect on Sexual maturation, in particular, estrus associated behaviors, estrogen and progesterone profiles and expression of kiss1 gene, kisspeptin receptor, estradiol receptor and progesterone receptor in the hypothalamus, pituitary and ovary. In the first experiment, 29 Saanen kids with 142,72 &plusmn; 10,61 days of age and 24,9 &plusmn; 4,26 kg weight were randomly assigned to three treatments namely: 1) exposure to active male (male group), 2) exposure to androgenized female (female group) and 3) control (control group). Daily observation to record estrus associated behaviors and weekly blood collections for estradiol and progesterone levels determination were made from May to October. Animals subjected to the male effect (active male or female) registered more estrus associated behavior than the control group. Social interaction had effect on tail position, vulva aspect, vocalization and mounts acceptance. There were significant differences among groups on estradiol levels. The male group registered higher estradiol concentrations than the control group. There was interaction group*collection on progesterone concentrations. Animals from the female group had significantly higher progesterone means in most collections than the other groups. The male group had statistically higher progesterone averages than the control group. In the second experiment, 16 Saanen kids at age of 138,37 &plusmn; 3,59 days and 22,75 &plusmn; 2,43 kg weight were randomly assigned to exposure to 1) active male (male group) and 2) control (control group). Animals were twice daily observed for 1 h: 30 minutes for registration of estrus associated behavior and twice weekly blood samples were collected for estradiol and progesterone assessment. Hypothalamic, pituitary and ovarian tissue samples were obtained before and sixty days after exposure to male effect for assessment of expression levels for kiss1 gene, kisspeptin receptor (kiss1R), estradiol receptor (ER) and progesterone receptor (PR). There were no differences among groups for standing mount. The male group registered higher frequency for mounting, however, the control group registered higher frequency for swelling vulva, restlessness and interacting. Progesterone concentrations and mRNA expression of kiss1, kiss1R, ERs and PR in the hypothalamus, ER&alpha; in the pituitary, ER&alpha;, ER&beta; and PR in the ovaries were significantly different among groups. The results suggest that mRNA expression of studied molecules differs between sexually immature and mature animals and the mRNA expression is influenced by the cyclic stage in post-pubertal animals.
203

Desempenho de cabritas Saanen submetidas a diferentes níveis de energia na dieta: perfil metabólico e hormonal / Performance of Saanen female kids submitted to different levels of dietary energy: hormonal and metabolic profile

Gabriela Facholi Bomfim 14 December 2012 (has links)
Considerando que a quantidade de energia ingerida pelo animal pode antecipar ou retardar o início da puberdade, este estudo tem por objetivo avaliar como diferentes níveis de energia influenciam o perfil metabólico, hormonal, consumo de alimento e o peso vivo de cabritas da raça Saanen em início de puberdade (entre 227 dias de idade e peso vivo de 28,38 &plusmn; 0,91kg até 304 dias de vida e peso vivo de 39,12 &plusmn; 1,47). Desse modo, as 21 cabritas experimentais foram submetidas a três dietas, sendo: T1) dieta controle, na qual atendeu 100% do requerimento dos animais (contendo níveis nutricionais preconizados segundo o NRC (2006)); T2) decréscimo de 20% de óleo de soja em relação à dieta controle e T3) acréscimo de 20% de óleo de soja em relação à dieta controle. Durante o período experimental foram realizadas pesagens e colheita de sangue semanalmente avaliação do desempenho dos animais bem como, de suas condições fisiológicas e reprodutivas, sendo essas obtidas através da dosagem de metabólitos (glicose, colesterol, triglicerídeo, proteína, ureia) e hormônios (progesterona (P4) e estradiol (E2). Ao avaliar o desempenho dos animais verificou-se que o tratamento controle apresentou peso vivo final e consumo da matéria seca superior (p&le;0,05) aos demais tratamentos, sendo o tratamento com acréscimo de 20% de óleo de soja em relação à dieta controle apresentou pior desempenho. Porém, ao analisar as médias dos hormônios E2 e P4 ao final do período experimental foi constatado que os animais que receberam dieta com acréscimo de energia tiveram médias superiores (p&le;0,05) aos demais quanto à concentração plasmática de progesterona, percentual de ovulação (considerando níveis de P4 acima de 1 ng/ml) e percentual de manifestação de estro (concentração de E2 acima de 30 pg/ml). Quanto aos metabólitos, os animais que foram submetidos ao decréscimo de energia em sua dieta apresentaram níveis de ureia e colesterol superiores (p&le;0,05) aos da dieta com acréscimo de energia. Contudo, com base nos resultados obtidos conclui-se que o ideal é manter a dieta controle, pois os índices para percentual de estro, ovulação e perfil metabólico são satisfatórios, bem como o consumo e peso vivo final dos animais. / Whereas the amount of energy intake by the animal can advance or delay the start of puberty, this study has for objective evaluate how different energy levels influence the metabolic profile, hormonal, food intake and body weight of female goat kids Saanen in early puberty (between 227 days of age and body weight of 28.38 &plusmn; 0.91 kg to 304 days of age and body weight of 39.12 &plusmn; 1.47). Twenty one Saanen female kids were submitted to three experimental diets: T1) control diet which met the requirement of 100% of the animals (containing nutrient levels recommended according to the NRC (2006)) T2) decrease of 20% oil soybean compared to the control diet and T3) increase of 20% soybean oil compared to the control diet. In the experimental period were performed weights and blood samples weekly for posterior evaluation of the performance of the animals as well as their reproductive and physiological conditions, which were obtained through the measurement of metabolites (glucose, cholesterol, triglyceride, protein, urea) and hormones (progesterone (P4) and estradiol (E2). In evaluating the performance of the animals was found that the control treatment showed higher final body weight and intake of dry matter (p &le; 0.05) than other treatments, the treatment with an increase of 20% soybean oil in relation to diet control showed poorer performance. However, when analyzing the means of hormones E2 and P4 at the end of the experimental period it was found that animals fed the diet with an increase of energy had higher mean (p &le; 0.05) to the other as the plasma progesterone concentration, percentage of ovulation (P4 levels more than 1 ng / ml) and percentage of expression of oestrus (E2 concentrations more than 30 pg / ml). As for metabolites, animals that were subjected to the decrease of energy in their diet had higher levels of urea and cholesterol (p &le; 0.05) to the diet with an increase of energy. However, based on the results obtained gives to conclude that the ideal is to maintain the control diet, because the indices for percentage of oestrus, ovulation and metabolic profiles are satisfactory, and the consumption and final body weight of the animals.
204

Isolamento e caracterização biológica e genotipica de Toxoplasma gondii de ovinos e caprinos / Isolation and biological and genotypic characterization of Toxoplasma gondii from sheep and goats

Alessandra Mara Alves Ragozo 10 April 2007 (has links)
O objetivo deste estudo foi o isolamento de Toxoplasma gondii de ovinos e caprinos e posterior caracterização genotípica desses isolados. Amostras de soros ovinos (495) de 36 Municípios do Estado de São Paulo e de caprinos (143) de seis Municípios dos Estados da Bahia (10), Paraíba (12), Rio Grande do Norte (7) e São Paulo (114) foram testadas, através do Teste de Aglutinação Modificado (MAT&ge;25) à presença de anticorpos anti-T. gondii. Dos animais amostrados, 24,2% e 32,2% dos ovinos e caprinos respectivamente, apresentaram-se positivos com títulos que variaram de 25 a 3200 em ambas espécies. Dentre os ovinos houve associação (p<0,001) entre sexo, idade e sistema de produção com a presença de anticorpos anti-T. gondii. Os caprinos apresentaram associação entre idade, sistema de produção, e raça com a soropositividade. Para o isolamento do agente o bioensaio em camundongos foi realizado utilizando-se pool de tecidos de ovinos (cérebro, coração e diafragma) e caprinos soropositivos (cérebro, coração e diafragma e masseter). Dos 82 bioensaios realizados com amostras de ovinos, 16 isolados (19,5%) foram obtidos. Houve associação entre o título de anticorpos anti-T. gondii e o isolamento do agente (p<0,001) com maior quantidade de isolados obtidos de animais com títulos mais altos. Para a caracterização genotípica das amostras utilizou-se a análise de polimorfismo de comportamento dos fragmentos de DNA gerados por enzimas de restrição (RFLP) sobre produtos do locus SAG2 amplificados pela PCR, que as identifica em genótipos I, II e III. Amostras do tipo I (87,5% dos ovinos e 100 % dos caprinos) e do tipo III (12,5% dos isolados de ovinos) foram obtidas e não houve o encontro de isolados tipo II ou mistas. Nos tecidos dos animais com títulos de anticorpos superiores a 400, e dos quais não se obteve o isolamento do agente pelo bioensaio (21 amostras de ovinos), foi realizada a nested-PCR das amostras primárias (homogeneizado de tecidos), não sendo obtida nenhuma amplificação. Amostras do tipo III não causaram óbitos nos camundongos e as tipo I causaram óbitos em 51,0% e 83,4% dos isolados de ovinos e caprinos, respectivamente. Houve associação entre a sobrevida dos camundongos infectados com o genótipo I de caprinos e ovinos (p<0,001). / The aim of this study was to analyze the SAG2 locus of Toxoplasma gondii isolated from sheep and goats in order to determine the frequency of occurrence of the three different lineages (types I, II and III). Serum samples of sheep (495) from 36 counties in São Paulo State and goat (143) from six counties in States of Bahia (10), Paraíba (12), Rio Grande do Norte (7) and São Paulo (114) were analyzed by the modified agglutination test (MAT&ge;25) for the detection of antibodies anti-T. gondii. Occurrence of antibodies anti-T. gondii was 24.2% and 32.2% in sheep and goats, respectively. The titers varied from 25 to 3200 in both species. Among sheeps, association of seropositivity (p<0,001) with sex, age, production system and presence of antibodies anti-T. gondii was observed. Association was also observed between the frequency of seropositive goats and age, production system and breed. For T. gondii isolation, pool of tissues of each seropositive sheep (brain, heart and diaphragm) and goat (brain, heart, diaphragm and masseter) were bioassayed in mice. From a total of 82 bioassay performed with sheep samples, 16 isolates (19.5%) were obtained. Association between antibodies anti-T. gondii titers and isolation was observed (p<0.001). Considering the goats, 12 isolates (42.6%) were obtained from 26 bioassays. For the genotypic characterization (genotype I, II and III), the restriction fragment length polymorphism (RFLP) was performed on fragments of the locus SAG2 amplified by PCR. Samples of type I (87.5% from sheep and 100% from goats) and type III (12.5% from sheep) was observed. Neither type II nor mixed samples were observed. In tissues samples from animals with antibodies titers above 400 in which T. gondii was not isolated (21 sheep sample), nested-PCR was performed and no amplification was observed. Mortality was not observed in the mice infected by the isolates type III. The isolates of type I from sheep and goats, respectively, killed 51.0% and 83.4% of the infected mouse. Association was also observed between mortality rate in infected mice and genotype I of sheep and goat (p<0.001).
205

Efeito da adição de antioxidantes enzimáticos na criopreservação do sêmen caprino / Effect of enzymatic antioxidants on goat cryopreserved semen

Rodrigo Otávio Correia da Silva 30 June 2011 (has links)
A caprinocultura no Brasil vem crescendo consideravelmente nos últimos anos. No entanto, este crescimento é limitado pela qualidade espermática pós-descongelamento, o que inviabilizaria a utilização de biotecnologias aplicadas à reprodução (e.g., inseminação artificial e transferência de embriões). Um dos motivos para a queda na qualidade espermática pós-descongelação é o ataque das espécies reativas de oxigênio (ROS), que podem levar a danos em membrana, acrossomo, mitocôndria e DNA. Uma alternativa para a melhora na qualidade espermática de amostras criopreservadas de caprinos seria o tratamento do meio diluidor com a antioxidantes. No entanto, é fundamental identificar a espécie reativa de oxigênio mais deletéria ao sêmen de caprinos para determinar o antioxidante ideal. O objetivo do presente estudo foi identificar a ROS mais deletéria ao sêmen de caprinos e, com isso, tratar o diluidor com antioxidantes específicos para a destruição da mesma. No experimento 1, amostras espermáticas de 12 bodes foram submetidas á incubação com 3 sistemas de produção de ROS e um subproduto da peroxidação de lipídeos, conhecida por também levar a danos oxidativos. As amostras espermáticas foram submetidas a incubação com xantina (20mM) e xantina oxidase (ânion superóxido), sulfato de ferro (4mM) e ascorbato (20mM- Radical hidroxila), peróxido de hidrogênio (H2O2; 20 mM) e malondialdeído (20 mM). Após a incubação as amostras espermáticas foram avaliadas quanto a morfologia, motilidade, membrana (eosina/nigrosina), acrossomo (Rosa Bengala/ Fast Green), mitocôndria (3,3 diaminobenzidina) e substâncias reativas ao ácido tiobarbitúrico (TBARS, avalia a susceptibilidade do espermatozóide ao estresse oxidativo). Os resultados do experimento 1 indicaram que a ROS mais deletéria ao espermatozóide caprino é o H2O2, que levou a danos de membrana plasmática e mitocôndria. Assim, no Experimento 2, o diluidor para a criopreservação do sêmen caprino foi suplementado com catalase e Glutationa Peroxidase (GPx), antioxidantes enzimáticos responsáveis pela destruição do H2O2. A análise estatística dos dois experimentos foi realizada através do SAS system for Windows. Os resultados do experimento 2 não revelaram efeitos benéficos para nenhuma das variáveis e com a utilização de ambos os antioxidantes. De fato, a catalase apreesntou efeitos deletérios à membrana plasmática das amostras criopreservadas com 240 UI/mL de catalase quando comparadas ao controle (13,42&plusmn;2,96% e 25,08&plusmn;4,80% de espermatozóides com membrana íntegra, respectivamente). De fato, estudos anteriores indicam que as concentrações de catalase em sêmen de caprinos são extremamente baixas, o que indicaria que o tratamento com as dosagens utilizadas de catalase pode ter sido excessivo. Além disto, diferentes antioxidantes aparentemente atuam em diferentes regiões do espermatozóide, sendo que, apenas a combinação de diferentes antioxidante poderia ser eficiente. Por outro lado, os resultados do Experimento 1 foram obtidos em amostras frescas, sendo que provavelmente, em amostras criopreservadas, a espécie reativa mais deletéria poderia ser outra. / The goat production in Brazil has grown considerably in recent years. However, this growth is limited by the post-thaw sperm quality, which would impais the use of biotechnologies applied to reproduction (e.g., artificial insemination and embryo transfer). One reason for the decline in sperm quality after thawing is the attack of reactive oxygen species (ROS), which can lead to damage of membrane, acrosome, mitochondria and DNA. An alternative to improve the quality of cryoprerved goat sperm samples would be the treatment of the extender with antioxidants. However, it is crucial to identify the reactive oxygen species more deleterious to semen of goats to determine the ideal antioxidant. The aim of this study was to identify the ROS more deleterious to semen of goats and thereby to treat the extender with specific antioxidants for the destruction of this ROS. In experiment 1, sperm samples from 12 goats were incubated with 3 systems of production of ROS and a by-product of lipid peroxidation, known to also lead to oxidative damage. The sperm samples were subjected to incubation with xanthine (20 mM) and xanthine oxidase (superoxide anion), iron sulfate (4 mM) and ascorbate (20mM-hydroxyl radical), hydrogen peroxide (H2O2, 20 mM) and malondialdehyde (20 mM). After incubation the samples were evaluated for sperm morphology, motility, membrane (eosin / nigrosin), acrosome (Rose Bengal / Fast Green), mitochondria (3.3 diaminobenzidine) and thiobarbituric acid reactive substances (TBARS, assesses the susceptibility of sperm to oxidative stress). The results of experiment 1 indicated that ROS most deleterious to the goat sperm is the H2O2, especially due to damages to the plasma membrane and mitochondria. Thus, in Experiment 2, the extender for cryopreservation of goat semen was supplemented with catalase and glutathione peroxidase (GPx), enzymatic antioxidants responsible for the destruction of H2O2. Statistical analyses were performed using the SAS system for Windows. The results of experiment 2 revealed no beneficial effects of the use of neither catalase oor GPx. In fact, catalase showed deleterious effects on the plasma membrane of cryopreserved samples; Samples treated with 240 IU / mL of catalase showed a lower percentage of sperm with intact membrane when compared with controls (13.42 &plusmn; 2.96 &plusmn; 4.80% and 25.08%, respectively ). In fact, previous studies indicate that concentrations of catalase in semen of goats are very low, which indicates that catalase treatment with the dosages used in the present study may have been excessive. Apparently different antioxidants work in different regions of the sperm, and only the combination of different antioxidant could be effective. Moreover, the results of Experiment 1 were obtained in fresh samples, and probably, in cryopreserved samples, other ROS could be the most deleterious.
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Efeito da gordura do leite de cabra sobre o valor D65oC do Mycobacterium fortuitum (NCTN 8573) / Effect of fat goat milk on value D65oC of Mycobacterium fortuitum (NCTN 8573)

Karina Ramirez Starikoff 19 October 2006 (has links)
O presente trabalho objetivou avaliar o efeito da gordura do leite caprino na resistência térmica do Mycobacterium fortuitum. A realização desta pesquisa é motivada pelos seguintes fatos: 1. a pasteurização lenta é amplamente utilizada para o beneficiamento do leite caprino destinado ao consumo e industrialização; 2. o binômio tempo x temperatura foi estabelecido com base na resistência térmica do Mycobacterium ssp; 3. o valor D expressa o tempo que se leva, a uma dada temperatura, para se reduzir um ciclo logarítmico de um microrganismo; 4. a gordura exerce efeito protetor sobre os microrganismos; 5. M. fortuitum é a espécie recomendada para testes iniciais, por ser menos patogênica e de crescimento rápido. Foram realizados dois experimentos (um com leite integral e outro com leite desnatado, com três repetições cada), utilizando-se amostras de cabras sadias. As amostras foram contaminadas com inóculo previamente padronizado e distribuídas em oito tubos com tampa, que foram submetidos a tratamento térmico em banho-maria à 65oC. Realizou-se a contagem das UFC/mL do leite contaminado antes do tratamento térmico (controle da contaminação) e dos tubos retirados nos tempos 0, 5, 10, 15, 20, 25 e 30 minutos. Realizou-se a diluição seriada até 10-7, com posterior semeadura em duplicata em placas de petri com meio Lowenstein-Jensen, incubadas por cinco dias à oC. Os resultados, em logarítmo, foram plotados em diagrama de dispersão, com posterior regressão linear para construção da curva de sobreviventes (ou curva de morte térmica), o valor D65oC foi calculado a partir da equação da reta obtida em cada repetição, e também a melhor curva obtida a partir das três repetições. Através dos resultados obtidos no presente trabalho obteve-se o valor D65oC do Mycobacterium fortuitum em leite caprino integral de 10,2 minutos e 8,61 minutos para o leite desnatado. Isso mostra que, na condição estudada a pasteurização lenta é capaz de reduzir 3,48 log de M. fortuitum em leite desnatado, e apenas 2,94 log em leite integral e, portanto, resultará em diferentes níveis de segurança ao consumidor. A variação nos valores D65oC observadas neste trabalho sugerem que a gordura não é a única responsável por essa diferença, pois houve variação entre as repetições realizadas no mesmo substrato. A variação entre os resultados em leite integral pode ser atribuída, pelo menos em parte, à composição da gordura que têm influência na resistência térmica dos microrganismos. A gordura do leite interfere negativamente na eficiência da pasteurização lenta sobre destruição de M. fortuitum. A importância dessa informação para a saúde pública é dependente, em primeiro lugar, da comprovação de que esse fenômeno é comum às espécies patogênicas de micobactérias, e determinar sua intensidade. A gordura não interfere no padrão de morte térmica no leite de cabra. / This work describes the results obtained to evaluate the effect of fat goat milk on thermal resistance of Mycobacterium fortuitum. This research is motivated for the following motives: 1. The holder pasteurization is extensive method using for the processing goat milk destined for consumption and industrialization; 2. The couple time x temperature was established for the thermal resistance of Mycobacterium ssp; 3. The value D express the necessary time, in a given temperature, to reduce a logarithmic cycle of microorganism; 4. The fat causes a protecting effect on the microorganisms; 5. Mycobacterium fortuitum is the specie recommended for beginnings tests, because it is less pathogenic and have fast growth. Two experiments were done (one using raw goat milk and another using skim goat milk, with three repetition each). The samples were contaminated with previous standard inoculum and distributed in eight tubes, that had been submitted a thermal treatment in water-bath in 65°C. The cfu/mL were counted in the contamined milk before the thermal treatment (contamination control) and the tubes pulled off in the times: 0, 5, 10, 15, 20, 25 e 30 minutes. Following was realized a series diluted until 10-7, with later spreaded in duplicate petri plates with medium Lowestein Jensen, incubated for five days in 37°C. The results obtained were represented in a logarithmic graph of dispersion diagram, with posterior linear regression for the construction survivor?s curve (or death thermal curve), the value D65oC was calculated from the equation of the straight line obtained in each repetition, and the best straight line obtained from the three repetitions too. Through the results obtained in the present work get a value D65oC of Mycobacterium fortuitum in raw goat milk the 10,2 minutes, and 8,61 minutes for skim goat milk, this mean that in these study conditions, the holder pasteurization is able to reduce 3,48 log of Mycobacterium fortuitum in skim milk and only 2,94 log in raw milk, and thus results in different security levels for the consumers. The variation observed in the values D65oC obtained in this work suggest that the fat doesn?t a unique responsible for this difference, because have a variation among the repetitions done in the same substrate. The variation between the results in raw milk can be attribute, in part, for the composition of fat that have a influence on the thermal resistance in the microorganisms. The fat milk interferes negatively in the holder pasteurization effective about the Mycobacterium fortuitum destruction. The importance on this information for the public health is dependent, in first moment, the proved that this phenomenon is common for the micobacteria pathogenic species, and determined its intensity. The fat doesn&#39;t interfere in the standard thermal death in the goat milk.
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Avaliação da produção avaliação da produção, composição físico-química, qualidade e perfil de ácidos graxos do leite de cabras Saanen alimentadas com diferentes níveis de óleo de arroz na dieta. / Evaluation of the production, physical-chemical composition, quality and fatty acid profile of milk from Saanen goats fed different levels of rice bran oil in the diet.

Vilanova, Marcele Sousa 21 February 2011 (has links)
Made available in DSpace on 2014-08-20T14:38:50Z (GMT). No. of bitstreams: 1 Tese_Marcele_Sousa_Vilanova.pdf: 948050 bytes, checksum: 7a7d6aa129c7207e116bace94c372823 (MD5) Previous issue date: 2011-02-21 / We tested the effect of two levels of ether extract based on rice oil concentrate, 30 Saanen goats during early lactation. The feeding was based on the ratio of 60% forage (alfalfa hay), and 40% commercial concentrate with two levels of lipids (3% and 5%). The variables were: average milk production, behavior of the lactation curve, milk chemical composition and total time of lactation against the profile of saturated, monounsaturated and polyunsaturated. The increase in the percentage of ether extract oil-based rice did not affect milk production, which presented as mean ± 2658 379 mL milk / goat / day, between 11 weeks and the chemical composition of milk, which characterized by having 3.78 ± 0.59% fat, 3.10 ± 0.18% crude protein, 4.46 ± 0.20% lactose and 12.19 ± 0.72% of total solids. However significant (P <0.05) fatty acid profile of milk, reducing the concentrations of saturated fatty acids, palmitic acid C16: 0, myristic C14: 0, capric C10: 0 and lauric C12: 0, which were higher in 3% treatment (26.87, 8.60, 5.90 and 3.06% respectively) and increasing concentrations of unsaturated C16: 1, C17: 1 and C20: 1 (0.43, 0.12 and 0.10%, respectively). The inclusion of rice bran oil at levels of 3% and 5% of dry matter in the diet of goats does not affect milk production and the chemical composition until the 11th week of lactation, however, is able to alter the fatty acid profile of significantly. / Testou-se o efeito de dois níveis de extrato etéreo a base de óleo de arroz no concentrado de 30 cabras Saanen durante a fase inicial de lactação. A alimentação baseou-se na relação 60% de volumoso (feno de alfafa), e 40% de concentrado comercial com dois níveis de extrato etéreo (3% e 5%). As variáveis estudadas foram: Produção, composição química, perfil de ácidos graxos saturados, mono e polinsaturados no leite. O aumento no percentual de extrato etéreo na ração não influenciou a produção de leite, que apresentou como média 2658±379 mL de leite/cabra/dia, no período de 11 semanas e nem a composição química do leite, que se caracterizou por ter 3,78 de gordura; 3,10 de proteína bruta; 4,46 de lactose e 12,19 de sólidos totais. O perfil de ácidos graxos do leite foi influenciado pelo acréscimo de extrato etéreo na ração. No tratamento de maior proporção houve um aumento das concentrações de ácidos graxos insaturados C18:1n 9c (Oléico) e C18:3n3, (25,79 e 0,80%, respectivamente) e no Ácido Linoléico Conjugada (CLA) que aumentou de 0,37 para 0,72% com o acréscimo de óleo; e uma redução dos ácidos graxos saturados: palmítico C16:0, mirístico C14:0, cáprico C10:0 e láurico C12:0, que foram maiores no tratamento 3% (26,87; 8,60; 5,90 e 3,06%, respectivamente).
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Stratégies innovantes de gestion du pâturage pour améliorer l'alimentation et lutter contre le parasitisme gastro-intestinal : pâturage mixte caprins/bovins et addition de vermicompost / Innovative strategies for grazing management to improve nutrition and fight against gastrointestinal parasitism : pâturage mixed goats / cattle and addition of vermicompost

D'Alexis, Séverine 03 October 2012 (has links)
Les systèmes d'élevage des petits ruminants au pâturage sont les plus répandus en zone tropicale humide mais l'exposition aux strongles gastro-intestinaux entraîne des pertes importantes de production. L'objectif de ce travail est d'évaluer un système de gestion mixte du pâturage associant diverses espèces animales permettant à priori d'accroître les performances via la réduction du parasitisme et!ou une meilleure alimentation. L'étude de la littérature a conduit à une méta-analyse confirmant de meilleures performances individuelles ou à l'hectare pour les ovins en mixte. Préalablement un dispositif visant à vérifier la non-transmission des larves d'Haemonchus contortus des caprinsaux génisses Créoles a été validé. Un second dispositif avec des chevrettes conduites en mixte, infestées ou pas par Haemonchus comortus (Ml et MnI) ont été comparées à des chevrettes contrôles infestées ou non (CI et CnI). Ce dispositif a été conduit pendant 2 ans avec des mesures du couvert pâturé, des mesures individuelles des quantités ingérées, de la digestibilité, du parasitisme et de la croissance. De plus fortes croissances ont étéobservées en pâturage mixte que les chevrettes soient infestées ou pas (43.25 et 31.68 glj pour MDI et MI vs. 32.44 et 17.91 glj) avec une moindre biomasse. Les mesures d'ingestion et d'ingéré digéré ont été corrélées aux croissances des chevrettes contrairement aux variables parasitaires et met en évidence le rôle de l'alimentation et de la résilience dans le bénéfice du pâturage mixte. Une autre gestion intégrée du pâturage a été étudiée basée sur l'utilisation du vermicompost et s' ant sur les mêmes leviers d'action: l'alimentation et le itisme / Systems of small ruminant grazing are most prevalent in the humid tropics but this environment exposes animals to gastro-intestinal with production losses. The objective ofthis thesis is to evaluate a system ofmixed management ofthe pasture combining various animal species, which allows a priori to increase animal performance by reducing the parasitism and/or better nutrition. The study of literature bas led to a meta-analysis confirming the better individual performances or calculated per ha for sheep reared mixed. The first experiment validated the non-transmission of Iarvae ofHaemonchus contortus from goats to heifers. In a second experiment, goats mixed with heifers, infested or not with Haemonchus contortus (Ml vs MnI) were compared with controls goats, reared alone, infested or not (CI and CNI). This deviee with a continuous driving was studied for two years with measurements on the sward, individual measures of intake, digestibility, parasitism and growth ofthe goats. The highest growth rates were measured with the mixed pasture as goats are infested or not (43.25 and 31.68 g / d for MN! and MI vs. 32.44 and 17,91 g / d) with lower biomass. The herbage intake and the digested herbage intake were well correlated to the growth rate, unIike parasitic variables, and highlight the role of diet in the benefit of mixed driving for goats. Therefore, the infested goats with Haemonchus, expressed greater resilience with improved growth performance compared with controls. Parallel to the study ofmixed pasture, another integrated management of grazing was studied, based on the use of vermicompost and relying on the same levers. namelv throuzh feedinz and parasitism
209

Effects of goat phenotype score on milk characteristics and blood parameters of indigenous and improved dairy goats in South Africa

Pambu, Roger Gollah 02 June 2012 (has links)
The aim of this study was to develop and examine the validity of using a phenotype scoring system (PTS), a new concept, in evaluating milk yield and constituents in different goat genotypes (Indigenous, British Alpines, Saanen and Toggenburg) raised in small scale production systems. Strategic decisions of small scale African farmers are mostly based on visual appraisal or body condition scoring (BCS) of their animals. BCS has been highly recommended as a means to evaluate both the energy and the health status of animals, especially in beef farming, but this method has been criticized for being too simple and too subjective because its evaluation is often done too late after the damage has already happened. Phenotype scoring (an approach which includes breed, udder size and BCS of the animal) is presented in this study as a better tool to evaluate milk yield in different goat genotypes raised under free range conditions. This has also been a good opportunity firstly to indicate which, among the three dairy breeds of goat under discussion, can adapt best to the African small scale farming system; secondly to review the relevance of some blood metabolites in characterizing milk production in different goat breeds and thirdly to study the milking capacity of the indigenous compared to the dairy goats raised under small scale production systems in South Africa. Thirty-two goats (8 Indigenous, 8 British Alpines, 8 Saanen and 8 Toggenburg) were raised in a free range system at the ARC-Irene experimental farm close to Pretoria. The experiment was a completely randomized experimental design with eight replicates per treatment group. Blood samples were collected by jugular venipuncture into 10 ml heparinised tubes in the morning before feeding on a weekly basis over a period of two months. Blood plasma was immediately aspirated after centrifugation (3000G), kept on ice and brought to the laboratory for the analysis of glucose, cholesterol, urea nitrogen (BUN) and free fatty acid (FFA) concentrations. Immediately after, all does were entirely milked (followed by 1ml oxytocin IM injection and the kids taken away for a period of four hours) before a second milking session took place to measure the daily milk yield of the does. Milk samples were analyzed for lactose, milk proteins, milk fat, milk urea-nitrogen (MUN) and milk somatic cell count (SCC). In addition body condition score (BCS), age and data related to the goat genotype (breed, udder characteristics) were recorded. Results confirmed that milk yield from dairy goats was higher (p<0.001) than the milk yield of indigenous goats during the entire period of study. Milk lactose values recorded in this study (between 3.9 and 4.9%) were the most stable constituent in goat’s milk. Milk protein concentration (between 3.1 and 4.5%) was significantly higher in the indigenous than in dairy breeds, especially in week one and from week four onwards. Milk fat values (between 3.3 and 7.7%) displayed a decline in all breeds; but as from week three, the fat in milk of indigenous does increased and from week five onwards, it remained significantly higher (p<0.001) compared to that of dairy breeds. In conclusion, the superiority of dairy breeds in milk yield was proven while the quality of indigenous goat milk was recognized. Studies on the characterization of milk production in different breeds revealed that the Toggenburg was superior to the other breeds, followed by the British Alpines and the Saanen; but the British Alpines showed a better adaptability to the environment followed by the Toggenburg and the Saanen. The latter could not produce milk without feed supplementation and lost most body condition as compared to the other breeds. Statistical analyses indicated that breed influenced milk yield, milk fat and the protein content of milk (especially in the Saanen and Toggenburg goats). BCS influenced fat content, lactose, milk proteins, MUN and SCC and also milk yield. Udder size influenced milk proteins and milk yield while udder attachment was associated with milk yield only. These results show that PTS, because it takes into account BCS, breed and udder size, is a better tool for predicting milk yield of goats herded in small scale farming systems. Africans interested in dairy goat farming should adopt PTS as a means to evaluate milk yield especially since milk is sold per volume and not by quality in Africa. Finally, milk from the indigenous goats is superior in terms of lactose, fat and protein content. The latter quality attributes can be used as selection criteria since the milk industry pays premiums for the fat and protein content of milk. / Thesis (PhD)--University of Pretoria, 2012. / Animal and Wildlife Sciences / unrestricted
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From folklore to feasibility: Commercialisation of South Africa's indigenous goats

Roets, Merida 18 October 2007 (has links)
Please read the abstract in the section 00front of this document / Thesis (PhD (Agricultural Economics))--University of Pretoria, 2007. / Agricultural Economics, Extension and Rural Development / PhD / unrestricted

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