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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.
91

Avaliação nutricional de farinhas de silagem de peixe em dietas para frangos de corte

OLIVEIRA, Camilla Roana Costa de 31 July 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-03-23T13:06:06Z No. of bitstreams: 1 Camilla Roana Costa de Oliveira.pdf: 827722 bytes, checksum: 6641f2926369a3e71dc540d71582767e (MD5) / Made available in DSpace on 2017-03-23T13:06:06Z (GMT). No. of bitstreams: 1 Camilla Roana Costa de Oliveira.pdf: 827722 bytes, checksum: 6641f2926369a3e71dc540d71582767e (MD5) Previous issue date: 2012-07-31 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Two studies were conducted to evaluate the effect of using four types of flour of fish silage in the diet of broilers. A total of 540 male broiler chickens of Cobb 500 were used. The experimental design was completely randomized design with 5 treatments consisting of a reference diet and four test diets containing 40% of waste from filleting fish with different sources of carbohydrates, producing flour with bran fish silage mesquite (SFA), flour scanning cassava (SFVM), corn meal (SFM), and cassava peel (SCM). In the first study, 180 chicks with eight days of age were housed in metabolic cages and divided into six replicates of 6 birds each to assess the chemical composition, energy values of silages and the transit time of feed in the gastrointestinal tract of birds. The AME and AMEn of flour fish silage were respectively for the SFA 3804kcal/kg and 3563 kcal / kg for SFVM 3807 kcal / kg and 3567 kcal / kg for SFM 3842 kcal / kg and 3600kcal / kg, and for SCM 3806 kcal / kg and 3566 kcal / kg and did not differ significantly between them. The diet with the highest transit time was 195.0 min and SFM had the lowest time been 154.3 min SFA. In the second experiment, a 360 chicks housed in cages located in six replicates of 12 birds each and subjected to the same treatment from the previous experiment in period 1 to 33 days, however, the finishing ration was used the same reference All treatments in order to leave no undesirable taste in the flesh of the poultry. For weight gain of 1 to 33 days all treatments differed from the reference treatment, resulting in compensatory gain final stage to less SFVM. The feed conversion ratio of 1 to 33 days had the worst result and the SFA SFVM, 1-42 days coversão not differ among treatments. There was no significant difference in glucose level in the birds fed and fasted state between treatments. Sensory tests showed no differences in the flavor of the meat of birds between treatments test and standard treatment. Based on the composition obtained, these fish silage has the potential to be used in diets for broilers, but the silage SFVM proved inferior others, weight gain provided by this silage was the smallest and the only treatment that differed reference. Diets containing fish silage did not affect the flavor of the meat of broiler chickens. / Foram realizados dois estudos com o objetivo de avaliar o efeito da utilização de quatro tipos de farinhas de silagem de peixe na dieta de frangos de corte. Um total de 540 frangos de corte machos da linhagem Cobb 500 foram utilizados. O delineamento experimental foi inteiramente casualizado, com 5 tratamentos constituídos de uma dieta referência e quatro dietas teste contendo 40% de resíduo de filetagem de peixe com diferentes fontes de carboidratos, produzindo a farinha de silagem de peixe com farelo de algaroba (SFA), farinha de varredura de mandioca (SFVM), farelo de milho (SFM), e casca da mandioca (SCM). No primeiro estudo, 180 pintos com oito dias de idade foram alojados em gaiolas metabólicas e distribuídos em seis repetições de 6 aves cada para a avaliação da composição química, os valores energéticos das silagens e o tempo de transito das rações no trato gastrointestinal das aves. Os valores de EMA e EMAn das farinhas de silagem de peixe foram respectivamente, para a SFA 3804kcal/kg e 3563 kcal/kg, para a SFVM 3807 kcal/kg e 3567 kcal/kg, para a SFM 3842 kcal/kg e 3600kcal/kg, e para a SCM 3806 kcal/kg e 3566 kcal/kg, não diferindo significativamente entre eles. A ração que apresentou maior tempo de trânsito foi a SFM 195,0 min e a que apresentou o menor tempo foi a SFA 154,3 min. No segundo experimento utilizaram-se 360 pintos alojados em boxes, distribuídos em seis repetições de 12 aves por unidade experimental e submetidos aos mesmos tratamentos do experimento anterior no período 1 a 33 dias, contudo, na fase de terminação foi utilizada uma mesma ração referência para todos os tratamentos, com o intuito de não deixar sabor indesejável na carne das aves. Para o ganho de peso de 1 a 33 dias todos os tratamentos diferiram do tratamento referência, obtendo ganho compensatório na fase final menos para a SFVM. A conversão alimentar de 1 a 33 dias teve o pior resultado a SFA e SFVM, de 1 a 42 dias a coversão não diferiu entre os tratamentos. Não houve diferença significativa para o nível glicêmico das aves no estado de alimentado e jejum entre os tratamentos. A avaliação sensorial não apresentou diferenças no sabor da carne das aves entre os tratamentos-teste e o tratamento padrão. Com base na composição obtida, estas silagens de peixe tem potencialidade para serem utilizadas em dietas para frangos de corte, porém a silagem SFVM mostrou-se inferior as demais, o ganho de peso proporcionado por essa silagem foi o menor e o único que diferiu do tratamento referência. As dietas contendo silagem de peixe não influenciaram o sabor da carne de frangos de corte.
92

Morfometria computacional de órgãos de frangos de corte submetidos a duas dietas distintas: suplementação mineral quelada versus suplementação mineral tradicional / Computational histomorphometry of broiler chickens organs submitted to two distinct feeds: chelated minerals and not chelated minerals diet.

Rafael Carvalho de Oliveira 25 September 2008 (has links)
Estudou-se a suplementação de minerais quelatados na nutrição de frangos de corte avaliando-se o desempenho zootécnico, a constituição e a morfologia óssea, hepática e intestinal destes animais, por meio da utilização de técnicas matemáticas computacionais, como visão computacional, reconhecimento de padrões e análises estatísticas multivariadas. Adicionalmente aferiu-se a resposta imunológica das aves testadas valendo-se do teste de inibição de hemaglutinação para Newscastle. Finalmente, fez-se a quantificação da porcentagem de cinzas ósseas no osso seco desengordurado em cada tratamento com a finalidade de comparar estes resultados àqueles de análise de imagens. Foi realizado um experimento fatorial 22, sendo os fatores sexo, macho e fêmea, e tipo de ração, premix mineral quelatado versus premix mineral tradicional. As aves foram alojadas na granja experimental da Fazenda do Glória Fundação de Amparo a Pesquisa da Universidade Federal de Uberlândia e, durante o estudo, anotaram-se os índices zootécnicos de cada grupo. Aos 49 dias de idade, as aves foram sacrificadas para coleta de órgãos para histomorfometria e verificação do rendimento de carcaça. Obtidas as imagens histológicas e macroscópicas foram empregadas as técnicas computacionais incluindo aquelas desenvolvidas pelo Grupo de Pesquisa em Visão Cibernética do Instituto de Física de São Carlos - Universidade de São Paulo. Os resultados demonstraram que dentre as variáveis aferidas ou não houve diferenças estatísticas entre os tratamentos ou, quando ocorreu diferença, essa indicou melhores resultados entre os machos tratados e resultados inferiores para as fêmeas tratadas, exceto quanto à microscopia intestinal e a quantificação da degeneração hepática. Em relação a primeira variável tanto os machos tratados quanto as fêmeas tratadas apresentaram os melhores resultados, mas na variável degeneração hepática os resultados também foram semelhantes entre machos e fêmeas, mas, nesse caso, o uso de quelatos foi prejudicial levando-se em conta o maior grau de lesão hepática entre os animais tratados. Assim, concluiu-se que o uso de minerais quelatados, de acordo com o esquema de arraçoamento estudado, foi positivo para frangos de corte machos e não o foi para fêmeas. Tal evidência aponta para a afirmação que, na pesquisa do uso de quelatos, os machos e as fêmeas deverão receber atenção diferenciada, tendo em vista que parecem responder distintamente ao produto. / This research studied the influence of chelated minerals in broilers chickens nutrition as well as the constitution and morphology of bone, liver and intestine of these animals, by means of the utilization of mathematical and computational techniques including computer vision, pattern recognition and statistical analysis. Additionally, the immunological response of the tested birds was investigated by using the haemagglutination inhibition test for Newcastle disease. We also measured the percentage of bone ash in dry and defatted bone in each handling with the purpose of comparing these results to those of images analysis. A factorial experiment was carried out, considering as factors sex, male and female, and kind of feed, while considering chelated minerals versus traditional minerals. The broilers were lodged in the Fazenda do Glória - FUNDAP-UFU experimental farm and, during this period, the performance indices of each group were estimated. At 49 days of age, the birds were sacrificed for collection of organs for histomorphometry and verification of the carcass. The obtained histological images were submitted to computational techniques analyses including some developed by the Cybernetic Vision Group of the Instituto de Física de São Carlos-USP. The results showed that the variables checked were diversely affected by the treatments. Better results were observed for treated males, with poorer performance obtained for treated females, except for intestinal microscopy and the quantification of the liver degeneration. Regarding intestinal microscopy, the treated males and females presented the best results. In which concerns the second variable, the results were similar between males and females, but in that case the groups that received chelated minerals presented bigger liver degeneration area than the control groups. Therefore, it was possible to conclude that the use of chelated minerals, according to the proposed breeder plan, was positive only for male broilers. Such evidence implies that, in the studies of chelated minerals, male and females should receive differentiated attention, having in mind that they respond differently to the products.
93

Avaliação do conforto térmico e do desempenho de frangos de corte confinados em galpão avícola com diferentes tipos de coberturas / Evaluation of thermal comfort and fibercement tiles on the performance of broilers confined in poultry houses with different types of roofing

Camila Lúcio Pereira 18 June 2007 (has links)
O objetivo deste estudo foi avaliar o conforto térmico em galpão para criação de frangos de corte, tanto do ponto de vista das variáveis ambientais do micro-clima criado por diferentes tipos de coberturas, como no que se refere aos reflexos causados sobre os animais confinados nesse ambiente. O experimento foi realizado de outubro a dezembro de 2005. Foram utilizadas 330 aves da linhagem Cobb e 330 aves da linhagem CPK Isa Hubbard, distribuídas em três tipos de instalação: com cobertura de telha cerâmica, com telha não convencional de cimento com polpa celulósica de eucalipto e com telha não convencional de fibrocimento reforçada com fibras de PVA (polivinil álcool). O desempenho térmico das coberturas foi avaliado a partir dos índices de conforto térmico (carga térmica radiante, índice de temperatura de globo e umidade e índice de temperatura de globo). Foi realizada simulação do desempenho térmico das coberturas pelo método dos elementos finitos (FEM). Para os animais foram avaliadas: as variáveis fisiológicas de termorregulação (temperatura superficial média e perda de calor por radiação), as variáveis produtivas (consumo de ração, ganho de peso e conversão alimentar) e, o comportamento ingestório de alimento e água. Os índices de conforto térmico confirmaram maior estresse térmico às 14 h. Para o ITGU a telha cerâmica apresentou desempenho equivalente ao das demais coberturas em todos os horários, porém, às 14 h a telha de fibrocimento reforçada com fibras de PVA apresentou desempenho térmico inferior ao da cobertura de cimento com polpa celulósica. No horário mais quente não houve diferença entre os valores de CTR, o que indica desempenho térmico similar entre as coberturas testadas. O método dos elementos finitos mostrou-se uma boa ferramenta de trabalho na simulação do comportamento térmico das coberturas. A diferença genética entre as linhagens está relacionada às maiores médias de TSM e menores médias de PCR apresentadas pela linhagem CPK Isa Hubbard. A linhagem Cobb apresentou melhores índices produtivos em todos os tratamentos. As três coberturas avaliadas apresentaram desempenho térmico satisfatório, configurando as \"telhas não convencionais\" como nova opção comercial de cobertura para instalações zootécnicas. / The aim of this study was to evaluate the thermal comfort in poultry houses for broiler chickens, considering environmental aspects of microclimate created by different types of roofing, and the consequences for animals confined in this environment. The trial was carried out from October to December 2005. It were used 330 Cobb line chicks and 330 CPK Isa Hubbard line chicks, distributed into three types of housing: ceramic tiles, non conventional tiles of cement with eucalypt cellulose pulp and non conventional tiles of fibercement reforced with PVA fibers (alcohol polyvinyl). The thermal performance of roofing was evaluated using thermal comfort indexes: radiant thermic load (RTL), globe temperature and humidity index (GTHI) and globe temperature (GT). The simulation of thermal performance of roofs was performed using the finite elements method (FEM). Considering the animals, it were evaluated physiological characteristics of thermoregulation (mean surface temperature and heat loss by radiation), productive parameters (feed intake, weight gain and feed conversion) and intake behavior of feed and water. The thermal comfort indexes confirmed higher thermal stress at 2 pm. For TGHI, the ceramic tiles presented similar performance compared with the other roofs in all times; however, at 2 pm the fibercement tile reforced with PVA fibers presented inferior thermal performance than the cellulose cement tile. At the hottest time, there was no difference between the RTL values, what indicates a similar thermal performance among the roofing tested. The FEM was showed as a good alternative on the thermal behavior simulation of roofing. The genetic difference among the broilers strains is related to the higher means surface temperatures and lower means for heat loss by radiation presented by the CPK Isa Hubbard line. The Cobb line presented better productive indexes in all treatments. The three roofs evaluated presented a satisfactory thermal performance, confirming the non conventional tiles as a new commercial option of roofing for animal housings.
94

Valores energéticos de alimentos determinados com aves em diferentes idades / Energy values of foods determinate with birds at different ages

Schneiders, José Luiz 22 June 2012 (has links)
Made available in DSpace on 2017-07-10T17:48:31Z (GMT). No. of bitstreams: 1 Jose_Luiz_Schneiders.pdf: 1748321 bytes, checksum: 37029be1961a45a283fde70f918c2191 (MD5) Previous issue date: 2012-06-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aimed to determine the energy values and the coefficients of different foods with broilers at different ages, two experiments were conducted: A digestibility and a performance trial. In the digestibility experiment the foods used were corn, soybean meal, soybean processed by steam heated, meat and bone meal, poultry by-produtct, fish meal, wheat bran, crude soybean oil and poultry fat. It was using the method of total excreta collection, with five trials, divided into five age groups (1-8, 11-18, 21-28, 31-38 and 41-48 days old). Were used 675, 450, 225, 180 and 180 broilers, respectively, in a completely randomized design with nine treatments and four replicates, totaling 36 experimental units. The second experiment evaluated the performance of broilers and the carcass yield using diets with the metabolizable energy values of corn, soybean meal and soybean oil obtained on the digestibility experiment at different ages. The animals were divided into stages 1-7, 8-21, 22-42 and 43-49 days of age. Four experiments were conducted, divided in phases according to ages: pre-starter, starter, grower and finish, were used, respectively 924, 924, 840 and 672 birds randomly distributed in 42 experimental units in a completely randomized design with seven treatments and six repetitions. At 42 and 49 days old two birds per pen were slaughtered to determine carcass yield, cuts and abdominal fat. Among the plant foods studied, the lower coefficients of apparent digestibility were obtained with wheat bran. Among the animal foods, the meat and bone meal had lower CMA and CMAn. Were adjusted to the LRP model the equations to the CMA of corn, soybean meal and soybean processed by steam heated. Other foods (except meat and bones meal) fitted to the linear regression model. The equations show that the digestibility of energy tends to increase with age, with the exception for soybean meal, which had higher digestibility with young birds. It follows that the age of the birds influences in the determinate of metabolizable energy value of foods. As a result of performance in the pre-starter and finishing just the feed conversion was significant. Already in starter and growth, there was significant difference in feed conversion and daily and medium weight gain. In slaughter at 42 days old, only the percentage of abdominal fat was significant / Com o objetivo de determinar os valores e os coeficientes energéticos de diferentes alimentos com frangos de corte em diferentes idades, foram realizados dois experimentos, sendo um ensaio de digestibilidade e outro de desempenho. No experimento de digestibilidade os alimentos avaliados foram o milho, farelo de soja, soja integral desativada, farinha de carne e ossos, farinha de vísceras de aves, farinha de resíduo de filetagem de tilápia, farelo de trigo, óleo de soja degomado e gordura de aves. Foi utilizado o método de coleta total de excretas realizando-se cinco ensaios, de acordo com as idades (1-8, 11-18, 21-28, 31-38 e 41-48 dias). Utilizando-se 675, 450, 225, 180 e 180 frangos de corte respectivamente em cada ensaio. O delineamento foi o inteiramente casualizado com nove tratamentos e quatro repetições totalizando em 36 unidades experimentais. O segundo experimento avaliou o desempenho de frangos de corte e rendimento de carcaça utilizando rações formuladas com diferentes valores de energia metabolizável do milho, farelo de soja e óleo de soja obtidos no experimento de digestibilidade nas diferentes idades. Foram realizados quatro ensaios, em fases de acordo com as idades: pré-inicial (1-7), inicial (8-21), crescimento (22-42) e terminação (43 a 49 dias de idade), onde foram utilizadas, respectivamente 924, 924, 840 e 672 aves distribuídas aleatoriamente em 42 unidades experimentais em um delineamento inteiramente casualizado, com seis tratamentos e sete repetições. Aos 42 e 49 dias de idade, duas aves por unidade experimental foram abatidas para determinação do rendimento de carcaça, rendimento de cortes e porcentagem de gordura abdominal. Entre os alimentos de origem vegetal estudados, os menores CMA e CMAn foram obtidos com o farelo de trigo. Entre os alimentos de origem animal, a farinha de carne e ossos apresentou menores CMA e CMAn da energia bruta. Houve ajuste das equações ao modelo LRP para o CMA do milho, farelo de soja e soja integral desativada. Demais alimentos (com exceção da farinha de carne e ossos) se ajustaram ao modelo de regressão linear. As equações demonstram que a digestibilidade da energia tende a aumentar com a idade, com exceção do farelo de soja, que teve maior digestibilidade com aves mais jovens. Conclui-se que a idade das aves influencia na determinação dos valores de energia metabolizável dos alimentos. Como resultados de desempenho, na fase pré-inicial e terminação somente a conversão alimentar foi significativa. Já nas fases inicial e crescimento, houve diferença significativa na conversão alimentar e ganho de peso médio e diário, sendo que as rações com maior inclusão do óleo de soja apresentaram melhor conversão alimentar e ganho de peso. Somente no abate aos 42 dias de idade a porcentagem de gordura abdominal foi significativa na ração que tinha maior inclusão do óleo de soja
95

OCORRÊNCIA NATURAL DE MICOTOXINAS EM MILHO (Zea mays L.) E SUA INFLUÊNCIA NO DESEMPENHO DE FRANGOS DE CORTE / NATURAL MYCOTOXIN OCCURRENCE IN MAIZE (Zea mays L.) AND INFLUENCE ON THE PERFORMANCE OF BROILER CHICKENS

Oliveira, Maurício Schneider 08 August 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Fungi can be found everywhere in nature and are known occur in maize. Those which have the ability to produce substances toxic to humans and animals, from its secondary metabolism, are named toxigenic fungi and the metabolites produced are called mycotoxins. Due to the presence of various toxigenic fungal species in maize crop, the occurrence of a large number of metabolites is expected. Besides occur in native forms, mycotoxins can occur in the form called masked, a result of changes in structure or chemical reactions with constituents of plants, making them undetectable to the analytical methodologies conventionally employed. Due to the damage that mycotoxins can cause to human and animal health, laws establishing maximum permitted levels of contamination in food has been proposed, but restricted to a small number of mycotoxins, partly due to analytical limitations and partly in consequence of the lack of database of natural occurrence of these contaminants in the native and masked forms. To evaluate the occurrence of fungal metabolites in maize, 148 samples were collected in the South region of Brazil. All samples were contaminated with at least 10 fungal metabolites and the higher co-occurrence detected in the same sample was 51 metabolites. In all maize samples analyzed were detected at least two mycotoxins adressed by Brazilian law (fumonisin B1 and fumonisin B2). Besides the research of the native forms of mycotoxins, analysis for masked fumonisin were performed. Seventy two maize samples were analyzed and masked fumonisin concentration was found up to two times greater than the concentration of fumonisins in native form. Furthermore, a positive correlation (R = 0.97) was found between the concentration of native and masked fumonisin. Based on this correlation, a mathematical prediction model to estimate the concentration of total fumonisins, based on the concentration of native fumonisins was generated. After knowing the co-occurence of several fungal metabolites in maize, the performance of broilers chickens submitted to diets with fungal culture material was evaluated. Body weight and feed conversion were significantly altered after 21 days of experiment in the group receiving diet containing higher concentrations of fusaric acid. The analytical methodologies enabled a first approach to study the co-occurrence of mycotoxins in their native and masked forms in maize naturally contaminated, collected in the South region of Brazil. The negative effect on the performance of broilers chickens, demonstrating that the co-occurrence of Fusarium mycotoxins have real impact in poultry and requires greater attention of the parties involved. / Fungos podem ser encontrados em toda a natureza e são de conhecida ocorrência na cultura do milho. Aqueles que possuem a capacidade de produzir substâncias tóxicas para humanos e animais, a partir de seu metabolismo secundário, denominam-se fungos toxígenos e os metabólitos produzidos são denominados micotoxinas. Devido a presença de diversas espécies fúngicas toxígenas na lavoura de milho, a ocorrência de um grande número de metabólitos é esperada. Além de ocorrerem em sua forma nativa, micotoxinas podem ocorrer na forma designada mascarada, resultado de alterações em sua estrutura ou de reações químicas com constituintes de plantas, tornando-as indetectáveis para as metodologias de análise convencionalmente empregadas. Em consequência aos prejuízos que as micotoxinas podem causar a saúde humana e animal, legislações estabelecendo limites máximos permitidos de contaminação em alimentos tem sido propostas, porém restritas a um pequeno número de micotoxinas, em parte devido a limitações analíticas e parte em decorrência da escassez de dados de ocorrência natural destes contaminantes na forma nativa e mascarada. Para avaliar a ocorrência de micotoxinas no milho, 148 amostras de milho foram coletadas nos estados pertencentes a região sul do Brasil. Todas as amostras estavam contaminadas com pelo menos 10 metabólitos fúngicos e a maior co-ocorrência detectada em uma mesma amostra foi 51 de compostos. Em todas as amostras de milho analisadas, foram detectadas pelo menos duas micotoxinas listadas na legislação brasileira (fumonisina B1 e fumonisina B2). Além da pesquisa das formas nativas de micotoxinas, foram realizadas análises para determinação de fumonisinas na forma mascarada. Setenta e duas amostras de milho foram analisadas e a concentração de fumonisinas mascaradas encontrada foi até duas vezes maior do que a concentração de fumonisinas na forma nativa. Ademais, uma correlação positiva (R=0.97) foi encontrada entre a concentração de fumonisinas na forma nativa e mascaradas. Baseado nesta correlação, foi gerado um modelo matemático de predição para estimativa da concentração de fumonisinas totais, baseado na medida de fumonisinas na forma nativa. Como consequência a constatação da co-ocorrência a diversas micotoxinas, o desempenho de frangos de corte submetidos a dietas contaminadas com materiais de cultivo fúngico foi avaliado. Peso corporal e conversão alimentar foram significativamente alterados aos 21 dias de experimento no grupo que recebeu dieta contendo maiores concentrações de ácido fusárico. As metodologias analíticas aplicadas permitiram uma primeira abordagem para estudo da co-ocorrência de micotoxinas na sua forma nativa e na forma mascarada em amostras de milho naturalmente contaminadas, coletadas na região sul do Brasil. O efeito negativo sobre o desempenho de frangos de corte observado, demonstrando que a co-ocorrência de micotoxinas do gênero Fusarium tem real impacto na avicultura e requer maior atenção das partes envolvidas.
96

Parâmetros genéticos para defeitos de pernas, características de desempenho e carcaça em frangos de corte / Genetic parameters of legs defects, performance and carcass traits in broiler chickens

Simone Fernanda Nedel Pertile 20 July 2011 (has links)
Os defeitos de pernas são decorrentes do rápido crescimento das aves, tornando-se necessário um estudo genético das associações entre essas características. Os objetivos deste estudo foram estimar os parâmetros genéticos para defeitos de pernas por escore visual, discondroplasia tibial, características de desempenho e carcaça, assim como estimar as tendências genéticas, ganho genético potencial e respostas correlacionadas, em uma linhagem de frangos de corte. O banco de dados utilizado neste estudo foi composto por registros de 128.459 aves, com informações de pedigree, manejo, desempenho, qualidades e defeitos de carcaça pertencentes a um rebanho elite de uma linhagem comercial de frangos de corte sob seleção. As características estudadas foram: os pesos vivos do animal aos sete (P7), 30 (P30) e 38 dias de idade (P38), peso ao abate (PA), peso eviscerado (PE), peso de peito (PPEI), peso de pernas (PPER), rendimento de carcaça (RCAR), rendimento de peito em relação ao peso ao abate (RPEI), rendimento de pernas em relação ao peso ao abate (RPER), eficiência alimentar (EFAL), defeito de pernas por escore visual (DPER), discondroplasia tibial (DT) e defeito de pernas total (DPERT). Para as características P7, P30, P38, PA, PE, PPEI, PPER, RCAR, RPEI, RPER, EFAL as análises genéticas foram realizadas pela metodologia dos modelos lineares clássicos, utilizando o método da Máxima Verossimilhança Restrita (REML) sob um modelo animal. Além da metodologia dos modelos lineares clássicos, as análises genéticas para as características DPER, DT e DPERT foram realizadas utilizando modelos lineares generalizados com função de ligação logit, devido à natureza categórica destas características, empregando-se modelo animal e modelo pai, com o método da quasi-verossimilhança penalizada (PQL). As análises foram obtidas utilizando-se o software ASREML®. As estimativas de herdabilidades obtidas para as características estudadas variaram de moderadas a altas, exceto para DT e DPERT, para as quais as estimativas de herdabilidades foram baixas. As estimativas de correlações genéticas entre as características de desempenho e carcaça e defeitos de pernas variaram de moderadas a altas, exceto para DPER e EFAL que apresentaram baixas correlações genéticas com as características de desempenho carcaça. As tendências genéticas para as características de desempenho e carcaça são indicativas que há seleção para características de peso vivo em diferentes idades e de desempenho e carcaça nesta linhagem, diferente do que acontece para as características de DPER, DT e DPERT, para as quais não há seleção evidente nessa linhagem. / The legs defects are caused by rapid growth of broilers, therefore it is necessary to study of genetic associations between these traits. The objectives of this study were to estimate genetic parameters for legs defects by visual score, tibial dyschondroplasia, performance and carcass traits, and to estimate the genetic trends, potential genetic gain and correlated response in a broiler line. The database used in this study consisted of records from 128,459 birds, containing pedigree information, management, performance, qualities and defects, of an elite flock from a commercial strain of broiler chickens under selection. The traits studied were: the live weight at seven (P7), 30 (P30) and 38 days old (P38), slaughter weight (PA), carcass weight (PE), breast weight (PPEI), leg weight (PPER), carcass yield (RCAR), breast yield (RPEI), legs yield (RPER), feed efficiency (EFAL), legs defect by visual score (DPER), tibial dyschondroplasia (DT) and legs total defects (DPERT). For the traits P7, P30, P38, PA, PE, PPEI, PPER, RCAR, RPEI, RPER, EFAL statistics and genetic analysis done through classical linear models methodology, using the method of Restricted Maximum Likelihood (REML) under an animal model. Besides the classical linear model methodology, genetic analyzes for the traits DPER, DT and DPERT were done using generalized linear models with logit link, due to the categorical nature of these traits, using an animal and sire models, by the method of penalized quasilikelihood (PQL). Full analyzes were obtained using the ASREML® software. Estimates of heritability obtained for the traits varied from moderate to high, except for DT and DPERT, which heritability were low. Estimates of genetic correlations between performance and carcass traits and leg defects varied from moderate to high, except for DPER and EFAL, which presented low genetic correlations with performance characteristics of the carcass. Genetic trends for performance and carcass characteristics indicate that selection occurs for body weight at different ages and performance and carcass traits in this strain, in a different way to the observed for traits of DPER, DT and DPERT, which no evident selection in this line was observed.
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Misturas de extratos vegetais como alternativas ao uso de antibióticos melhoradores do desempenho nas dietas de frangos de corte / Blends of plants extracts to substitute the antibiotics as growth promoters in broilers diets

Pricila Vetrano Rizzo 27 August 2008 (has links)
Dois experimentos foram realizados com o objetivo de avaliar a eficácia da suplementação de diferentes misturas de extratos vegetais nas rações de frangos de corte como melhoradores do desempenho. Para o ensaio de desempenho, foram utilizados 1350 pintos de corte em blocos casualizados, com 6 repetições e 5 dietas experimentais: CN - controle negativo (dieta basal); CP - controle positivo, CN com 10 ppm de avilamicina; ME1 - CN com produto contendo 200 ppm de óleos essenciais de cravo, tomilho, canela e pimenta; ME2- CN com 100 ppm do produto comercial composto por óleos essenciais sintéticos de orégano e canela e óleoresina de pimenta microencapsulados; ME3 CN 500 ppm do produto comercial constituído por óleo de eucalipto, óleo essencial de canela-da-China, folhas de boldo-do-Chile e sementes de feno-grego, na fase inicial e 1200 ppm nas fases de crescimento e final. As aves foram criadas em cama reutilizada com a finalidade de proporcionar desafio à criação. Foram realizadas análises de contagem de oocisto de Eimeria na cama antes do início e após o término do experimento e os exames das amostras de cama não revelaram presença de oocistos de Eimeria. Ganho de peso, consumo de ração, conversão alimentar, viabilidade, uniformidade do lote aos 42 dias de idade e características de carcaça foram avaliados. Aos 23 dias de idade, 80 frangos criados separadamente e submetidos aos mesmos tratamentos do experimento de desempenho foram transferidos para gaiolas de metabolismo e, dos 27 aos 30 dias de idade, foi realizado o ensaio de metabolismo pelo método de coleta total de excretas e determinados a energia metabolizável e o coeficiente de digestibilidade da proteína bruta das dietas. Quatro aves de cada tratamento, criadas separadamente, foram sacrificadas para realização da morfometria do proventrículo, moela, fígado, pâncreas e intestino delgado. Também foi anotado o comprimento do intestino delgado. As análises estatísticas foram realizadas no programa estatístico SAS e, no caso de diferença significativa, as médias comparadas pelo teste de Dunnett. As inclusões de misturas de extratos vegetais nas dietas de frangos de corte não foram capazes de exercer efeito significativo (P<0,05) quando comparadas às dietas controles CN e CP. Tal fato pode estar relacionado com a ausência de desafio nas condições experimentais aliado à utilização de dietas com ingredientes de alta digestibilidade que permitiram que os frangos de corte expressassem todo o seu potencial tornando indetectável qualquer melhora ocasionada pela inclusão de antibiótico ou de misturas de extratos vegetais nas dietas. Conclui-se que, nas condições em que foi realizado este estudo, as dietas contendo misturas de extratos promoveram desempenho semelhante ao das dietas CN e CP. / Two trials were carried out to evaluate different blends of plants extracts in broilers diets. Dietary treatments were fed to 1,350 one-day-old male Cobb chicks distributed in a randomized complete block design with six repetitions. The experimental diets were: NC - negative control (basal diet); PC - positive control, NC with 10 ppm of avilamycin; BPE1 - NC with 200 ppm of a blend containing natural essential oils of clove, thyme, cinnamon and capsicum microencapsulated; BPE2 - NC with a commercial product containing 100 ppm of synthetic cinnamaldehyde and carvacrol and natural capsicum oleoresin microencapsulated; BPE3 - NC with 500 ppm of commercial product containing eucalypt oil, essential oil of Chinese cinnamon, leaves of Chilene boldo and seeds of fenu-Greek in the initial phase and 1200 ppm in the grower and finisher phases. The amount of Eimeria oocist in the litter was analyzed before and after the trials and the results were negative to the presence of Eimeria oocist. Weight gain, feed intake, feed conversion, viability, uniformity at 42 days of age and carcass characteristics were evaluated. At 23 days of age, 80 chickens, raised at the same conditions and receiving the same diets as the chickens from the performance trial, were transferred to metabolic cages in a randomized complete block design and four repetitions. From 27 to 30 days of age, the total excreta collection method was applied to determine the apparent metabolizable energy and the crude protein digestibility of the dietary treatments. Four chickens from each treatment were sacrificed to evaluate relative weight of proventriculus, gizzard, liver, pancreas and small intestine. The length of the small intestine was also determined. The statistical analyses were carried out by SAS and the means were compared using the Dunnet test. The dietary utilization of plants extracts had no effect on parameters evaluated when compared to NC or PC. Possibly, the lack of challenge at poultry house and the high digestibility of the experimental diets made undetectable any improvement that could be shown by the inclusion of additives in the diet. It can be concluded that in these experimental conditions, the chickens fed on BPE1, BPE2 or BPE3 diets showed the same performance than NC or PC diets.
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Effect of dietary threonine level on productivity and carcass characteristics of Ross 308 broiler chickens

Ngomani, Delisile January 2019 (has links)
Thesis (M.Sc. (Animal Production)) --University of Limpopo, 2019 / Two experiments were conducted to determine the effect of dietary threonine level on production performance and carcass characteristics of Ross 308 broiler chickens. In each experiment the diets were isocaloric and isonitrogenous but with different dietary threonine levels.The first part of the study determined the effect of dietary threonine level on feed intake, growth rate, mortality and carcass characteristics of Ross 308 broiler chickens aged between Day 1-21. A total of 150 unsexed day-old chicks were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having ten chickens per replicate. The second part of the study determined the effect of dietary threonine level on feed intake, digestibility, growth rate, mortality and carcass characteristics of male Ross 308 broiler chickens aged between Day 22-42. Seventy-five male chickens were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having five chickens per replicate. A quadratic regression model was used to determine the optimal productivity of the chickens while a General Linear Model (GLM) procedures for the statistical analysis of variance was used to detect dietary treatment effects. Where there were significant differences (P<0.05), Turkey’s honestly significant difference test (HSD) was used for mean separation. The chickens were slaughtered at the ages of 21 and 42 days for Experiments 1 and 2, respectively, following ethical standards as recommended by the University of Limpopo Animal Research Ethics Committee (AREC/12/2017: PG). Two chickens per replicate for both studies were slaughtered for the determination of carcass characteristics (carcass and organ weights, gut organ digesta pH and gastro-intestinal length measurements). Dietary threonine levels used in this experiment affected (P<0.05) feed intake, growth rate, live weight, metabolisable energy (ME) intake, nitrogen retention, feed conversion ratio and gut organ weights and lengths of unsexed Ross 308 broiler chickens aged 21 days. Dietary threonine level did not affect (P>0.05) diet digestibility. Feed conversion ratio, pH of the proventriculus digesta, gut intestine length and caecum length of unsexed broiler chickens were optimized at different dietary threonine levels of 9.6, 8.5, 6.6 and 8.4 g/kg DM, respectively. Dietary threonine levels had an effect (P<0.05) on feed intake, diet digestibility, metabolizable energy, live weight, proventriculus pH values, GIT length, gut organ and carcass organ weights of male Ross 308 broiler chickens between 22 to 42 days of age. Proventriculus and large intestine weights were optimized at different dietary threonine levels of 7.5 and 9.1 g/kg DM feed, respectively. Dietary threonine level did not affect (P>0.05) growth rate, feed conversion ratio of male Ross 308 broiler chickens between 22 to 42 days of age. It is concluded that dietary threonine levels used in this study affected production performance of younger broilers (Day 1-21) more than that of older birds (Day 22-42). However, production variables were optimized at different dietary threonine levels. This has implication on diet formulation for the chickens and no linear response could be established / National Research Foundation (NRF), and the Department of Agriculture, Forestry and Fisheries (DAFF)
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Effects of natuzyme® supplementationon fibre digestion, growth and carcass characteristics of male ross 308 broiler chickens

Mashau, Pfuluwani January 2020 (has links)
Thesis (M.A. (Agricultural Management) -- University of Limpopo, 2020 / Two experiments were conducted to determine the effect of natuzyme50® supplementation on fibre digestion, growth and carcass characteristics of Ross 308 broiler chickens aged one to 42 days. The first experiment determined the effect of natuzyme50® supplementation on feed intake, growth and live weight of unsexed Ross 308 broiler chickens aged one to 21 days. Unsexed day old chicks were assigned to 4 different natuzyme50® supplementation levels of 0.0 (UNZ0), 0.75 (UNZ0.75), 1.0 (UNZ1.0) and 1.5 (UNZ1.5) g/kg DM feed, replicated 4 times and each replicate having 10 chicks. A general linear model (SAS, 2008) was used to analyse the data. Ross 308 broiler chickens on a diet supplemented with 1.5g of natuzyme50® per kg DM had higher (P<0.05) DM feed intake than those on a diet not supplemented with natuzyme50®. Natuzyme50® supplementation did not (P>0.05) have any significant effect on growth rate of unsexed Ross 308 broiler chickens aged one to 21 days. Unsexed broiler chickens on a diet supplemented with 1.5g of natuzyme50® per kg DM had higher (P<0.05) live weights than those on a diet not supplemented with natuzyme50® at the age of 21 days The second experiment determined the effect of natuzyme50® supplementation on feed intake, growth performance and carcass characteristics of male Ross 308 broiler chickens aged 22 to 42 days. The chickens aged 22 days were assigned to 4 natuzyme50® supplementation levels of 0.0 (MNZ0), 0.75 (MNZ0.75), 1.0 (MNZ1.0) and 1.5 (MNZ1.5) g/kg DM feed, replicated 4 times and each replicate having 6 chickens. The diets were isocaloric and isonitrogenous. A general linear model (SAS, 2008) was used to analyse the data obtained. Natuzyme50® supplementation level had no effect (P>0.05) on feed intake of male Ross 308 broiler chickens aged 22 to 42 days. However, natuzyme50® supplementation level had effect (P<0.05) on growth rate of male Ross broiler chickens aged 22-42 days. Male Ross 308 broiler chickens on a diet supplemented with 1.5g of natuzyme50® per kg DM had higher (P<0.05) growth rates than those on a diet supplemented with 1.0g of natuzyme50® per kg DM. However, the significant differences did not extend to birds on a diet not supplemented with natuzyme50®, diets supplemented with 0.75 or 1.5g of natuzyme50® per kg DM which vi showed similar (P>0.05) growth rates. Natuzyme50® supplementation levels used had no effect (P>0.05) on carcass, breast and drumstick weights of male Ross 308 broiler chickens. Natuzyme50® supplementation levels had no effect (P>0.05) on meat juiciness. However, natuzyme50® supplementation improved (P<0.05) meat tenderness and flavour. Increasing natuzyme50® level of supplementation decreased (P<0.05) meat shear force values. It is concluded that natuzyme50® supplementation improved (P<0.05) meat tenderness and flavour, and reduced meat shear force values of male Ross 308 broiler chickens. However, further studies are recommended to ascertain the current results. / Edu-loan
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Detecting a Probiotic Product Within the Gut of Broiler Chickens

Pisula, Anneka 01 August 2018 (has links) (PDF)
As of January 2017, the U.S. poultry industry banned the use of antibiotics and now relies on alternatives such as probiotics to help protect animal health. Although probiotic use is not a new concept in the poultry industry, identifying the best combination of bacterial strains to generate an effective probiotic formula requires further investigation. This study aimed to detect a probiotic product of four bacterial strains (Pedioccoccus acidilactici, Pediococcus pentosaceus, Lactobacillus plantarum, and Bacillus subtilis) in a feeding trial with broiler chickens. Birds given the probiotic were predicted to show an improved growth performance with the probiotics colonizing the gut. Ninety-six broiler chickens were equally divided into 3 treatment and 3 control pens. During the 25-day experiment, birds were fed a starter diet (days 0-11) and a grower diet (days 12-25). Experimental birds were administered the probiotic product via the drinking water at a concentration of 3.1×104 CFU/ml. Control birds had an equivalent amount of dextrose filler added to their water supply. Feces were collected hourly on day one and daily thereafter. On days 1, 22, and 25 of the experiment, 2 birds from each pen were euthanized for gut sampling. Lumen and mucosa samples were collected from the duodenum, jejunum, ileum, and ceca. Species-specific and strain specific PCR primers were employed for probiotic detection. Wild strains of P. acidilactici, P. pentosaceus, and L. plantarum were detected in the feeds, inhibiting detection of the probiotic strains when using species-specific PCR primers. Strain-specific primers were used to detect the probiotic Pedioccoccus acidilactici and Lactobacillus plantarum strains. B. subtilis was detected in feces within one hour of probiotic administration and was predominantly detected in experimental birds only. Both P. acidilactici and L. plantarum probiotic strains were initially detected in the feces of treated birds within two hours of probiotic administration and again ten days later. Both L. plantarum and B. subtilis were seen only in treated bird gut samples. L. plantarum was predominantly detected in the ceca near the end of the small intestine. P. pentosaceus was observed more often in treated gut samples and P. acidilactici was the least commonly detected probiotic strain. All administered bacteria were rarely seen in mucosa samples. Feed-endogenous P. acidilactici and L. plantarum strains became progressively more detectable in the mucosa along the gastrointestinal tract suggesting gut colonization, however, probiotic strains did not appear to colonize the mucosa of treated birds. Although probiotic strains were no longer detected after product removal, all probiotic strains were detected in feces and gut samples during probiotic administration, suggesting the bacteria can colonize the gut. Probiotic supplementation did not result in significant differences in body weight gain, feed intake, or feed conversion ratio. However, birds growing in a more stressful environment than the carefully controlled experimental set up used here may show probiotic-related effects. This study identified that the probiotic bacteria appeared to survive the gastrointestinal tract, exhibited a transit time of 1-2 hours, could possibly colonize chickens, and localized near the end of the chicken gut.

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