Incorporation of full-fat flaxseed, and to a lesser extent, canola seed in diets to produce n-3-enriched products has attracted interest in the poultry industry. However, high amounts of nonstarch polysaccharides (NSP) in oilseeds compromise their nutritive value. The objectives of the current research were to develop enzyme supplements effective in cell wall depolymerization and viscosity reduction, particularly in flaxseed; to evaluate the effects of enzyme addition and feed processing on oil utilization and egg n-3 fatty acid deposition in broiler chickens and laying hens fed oilseed-containing diets; to characterize the NSP hydrolysis products and to investigate the effects of diet type and enzyme addition on growth performance and the incidence of necrotic enteritis (NE) in broiler chickens challenged with Clostridium perfringens. Results showed that diets containing high levels of flaxseed reduced egg production and shell quality in laying hens, and impaired final body weight and feed conversion ratio (FCR) in broiler chickens. Reducing flaxseed particle size via grinding did not improve the growth performance of broiler chickens, whereas diet pelleting showed more pronounced and beneficial effects in improving the nutritive value of flaxseed, particularly when intact seeds were used. Multicarbohydrase supplementation resulted in a significant depolymerization of cell wall polysaccharides in soybean, canola and flaxseed meals, which was followed by the production of water-soluble NSP hydrolysis products, and the reduction of flax mucilage viscosity in vitro was also evident. Enzyme addition to flaxseed-containing diets improved FCR of broiler chickens and egg production performance of laying hens, and facilitated egg n-3 fatty acid deposition. The C. perfringens challenge caused intestinal NE lesions and increased the mortality of broiler chickens with the highest NE mortality and intestinal C. perfringens counts observed in those fed flaxseed-containing diets. Enzyme supplementation to diets containing high levels of water-soluble NSP (wheat/barley- or wheat/barley/flaxseed-based) facilitated post-disease compensatory growth in pathogen challenged birds. This was accompanied by a numerical reduction of intestinal C. perfringens by 1.4 log10 cfu/g in birds fed the flaxseed-containing diets. Such findings indicated that enzyme addition may be used as a nutritional strategy to reduce the risk of NE development in broiler chickens.

Incorporation of full-fat flaxseed, and to a lesser extent, canola seed in diets to produce n-3-enriched products has attracted interest in the poultry industry. However, high amounts of nonstarch polysaccharides (NSP) in oilseeds compromise their nutritive value. The objectives of the current research were to develop enzyme supplements effective in cell wall depolymerization and viscosity reduction, particularly in flaxseed; to evaluate the effects of enzyme addition and feed processing on oil utilization and egg n-3 fatty acid deposition in broiler chickens and laying hens fed oilseed-containing diets; to characterize the NSP hydrolysis products and to investigate the effects of diet type and enzyme addition on growth performance and the incidence of necrotic enteritis (NE) in broiler chickens challenged with Clostridium perfringens. Results showed that diets containing high levels of flaxseed reduced egg production and shell quality in laying hens, and impaired final body weight and feed conversion ratio (FCR) in broiler chickens. Reducing flaxseed particle size via grinding did not improve the growth performance of broiler chickens, whereas diet pelleting showed more pronounced and beneficial effects in improving the nutritive value of flaxseed, particularly when intact seeds were used. Multicarbohydrase supplementation resulted in a significant depolymerization of cell wall polysaccharides in soybean, canola and flaxseed meals, which was followed by the production of water-soluble NSP hydrolysis products, and the reduction of flax mucilage viscosity in vitro was also evident. Enzyme addition to flaxseed-containing diets improved FCR of broiler chickens and egg production performance of laying hens, and facilitated egg n-3 fatty acid deposition. The C. perfringens challenge caused intestinal NE lesions and increased the mortality of broiler chickens with the highest NE mortality and intestinal C. perfringens counts observed in those fed flaxseed-containing diets. Enzyme supplementation to diets containing high levels of water-soluble NSP (wheat/barley- or wheat/barley/flaxseed-based) facilitated post-disease compensatory growth in pathogen challenged birds. This was accompanied by a numerical reduction of intestinal C. perfringens by 1.4 log10 cfu/g in birds fed the flaxseed-containing diets. Such findings indicated that enzyme addition may be used as a nutritional strategy to reduce the risk of NE development in broiler chickens.

Orientador: Tereza Cristina Cardoso Silva / Banca: Roberto Gameiro de Carvalho / Banca: Andréa Fontes Garcia / Resumo: O Vírus da Bronquite Infecciosa, assim como outras doenças infecciosas, é um dos principais limitantes à produção de frango de corte. O coronavírus responsável por causar essa doença influencia na perda de desempenho das aves acometidas prejudicando o perfil financeiro do setor. Considerando o Brasil hoje, o segundo maior exportador mundial de carne de frango e esse coronavírus altamente contagioso por suas perdas em níveis financeiro e industrias, este trabalho objetivou avaliar a presença do vírus em uma região do noroeste paulista sem vacinação compulsória. Para investigar a presença de anticorpos contra o mesmo, foram coletados de 100 aviários 10 soros de cada, os animais eram alojados de forma aleatória em 2 regiões que formam um ângulo de 360º com a unidade de abate integradora parceira deste trabalho. Por fim, as amostras foram mensuradas através do teste de ELISA® indireto, que abordou o método estatístico X 2 . Os resultados indicaram que há circulação do vírus p<0.1, demonstrando uma necessidade em se adotar um novo protocolo de vacinação para a região. / Abstract: - Infectious Bronchitis Virus is one of the main limiting factors for the production of broiler chickens, and is still responsible for the loss of performance of these birds and even motivating high mortality rates. Considering Brazil today, the second largest exporter of poultry in the world and this highly contagious coronavirus, due to its losses to the financier of the industries, this work aimed to evaluate the presence of the virus in a region of the northwest of São Paulo without compulsory vaccination. Thus, to investigate the presence of antibodies against it, 10 sera of each 100 birds were randomly housed in 2 regions that form a 360 degree angle with the integrating slaughter unit partner of this work. Finally, the samples were measured through the indirect ELISA, which approached the chi - square statistical method. The results indicated that there is circulation of the virus p <0.1, demonstrating a need to adopt a new vaccination protocol for the region / Mestre

Social scientists and food studies scholars have shown an enduring interest in how food is produced in our largely industrialized food system. However, there has been little research about the organization of labor on industrialized farms. These sites of production are mostly privately owned and hidden away from researchers and journalists, who are often perceived as critics or activists by farmers and other agriculturalists. My dissertation fills this gap by focusing exclusively on industrialized contract broiler farms. Contract broiler farming is a model where farmers agree to raise chickens for meat for a set amount of time, at a rate of pay based on the ratio of feed to chicken weight at slaughter. Farmers invest in the built infrastructure to execute this process, but the company they contract for is mostly in control of the upstream and downstream supply and processing chains that depend on the production of the broiler chicken for their continued functioning. I use archival, interview, and ethnographic data to detail the history of broiler farming, the emergence of contracting, and what the experience of it is like today. The most significant and novel part of this project is my ethnographic data collected over six months spent working on two broiler farms contracted with one of the largest firms in the US. To date, no other researchers have been able to gain this level of access. In this dissertation, I begin by exploring the role of management, detailing how the structure of the farming contract and ambiguous supervisory oversight facilitates farmer’s compliance with company demands. Then, utilizing agricultural and labor scholarship on deskilling in the labor process, I explore how poultry farming has become deskilled, robbing farmers of autonomy, the opportunity to agitate for better labor conditions, and ultimately eroding the intimate knowledge necessary to execute successful animal husbandry. Finally, I explore the games farmers play at work. While these games obscure how surplus value is appropriated from the farmer by the contracting firm, they also demonstrate farmer’s resistance and acquiescence to their deskilling and loss of autonomy.

Made available in DSpace on 2014-06-11T19:28:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-15Bitstream added on 2014-06-13T20:57:59Z : No. of bitstreams: 1 hada_fh_me_jabo.pdf: 456451 bytes, checksum: 872a572717a21550d72964f8a222f7fa (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do trabalho foi averiguar quais seriam as possíveis alterações metabólicas e bioquímicas, principalmente relacionadas à capacidade antioxidante muscular, quando frangos de corte são submetidos a diferentes alterações nos macronutrientes e da adição do selênio na dieta, bem como o desempenho de frangos de corte ao serem submetidas ao estresse térmico de calor de forma aguda. Foram utilizados pintos de corte de um dia de idade, criados até o 7º dia com dieta comercial, no 8° dia as aves foram submetidas às dietas experimentais. A alteração realizada na proteína causou maior influência sobre o desempenho e nos cortes comerciais, quando comparados com as alterações no carboidrato e lipídeo. A adição de selênio influenciou positivamente a viabilidade criatória em aves arraçoadas com baixa proteína, porém não influenciou o rendimento de carcaça, peito, coxa+sobre-coxa. Estas alterações causam alterações metabólicas e bioquímicas nos frangos, sendo que o nível protéico causou grande impacto sobre os níveis de triglicérides e ácido úrico. Frangos submetidos a estresse por calor apresentaram alterações nas concentrações dos metabólitos plasmáticos, e na atividade da catalase em aves arraçoadas com diferentes alterações na dieta. A adição de selênio não influenciou os parâmetros sanguíneos dos 14 aos 42 dias de idade, porém houve influência no ácido úrico aos 28 dias, triglicérides, ácido úrico e CK aos 35 dias e para glicose aos 42 dias quando as aves foram submetidas a estresse por calor. Mas não houve efeito sobre a catalase, superóxido dismutase e glutationa peroxidase, mas observou-se influência sobre o TBARS. / The objective of the work was to check out which would be the possible metabolic and biochemical alterations, mainly those concerning the muscular anti-oxidant capacity as a broiler chicken is submitted to different changes in the nutrients, and the addition of selenium in the diet, as well as the performance of the broiler chicken being submitted to an acute heating stress. It was used broilers with one day of life, raised up to their seventh day with a conventional diet at the eight; the birds were submitted to experimental diets. The change brought about in protein impacted somewhat the performance and the commercial cuts, if compared with the alterations in the carbohydrate and lipids. The selenium addition influenced positively the breeding viability in birds feed with low protein, however the influences over the carcass yield, trunk and legs were not significant. This different changes gave rise to both metabolic and biochemical in broiler. The protein levels offered great impact on the levels of uric acid, triglycerides. Broilers submitted to stress due to heat presented alterations in the concentrations of the plasmatic metabolites, and also in the catalase in birds fed with different alterations in their diets. The addition of the selenium didn’t influence the sanguineous parameters from the 14th to the 42nd days of age. However, there was a change in the uric acid at the 28 days, triglycerides, uric acid and CK at the 35th days. As to the glucose, at the 42nd days as the birds were stressed by the heat. However did not alter the catalase enzymes, superóxide dismutase and glutationa peroxidase but an influence was held once the TBARS.

Made available in DSpace on 2014-06-11T19:28:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-24Bitstream added on 2014-06-13T20:18:07Z : No. of bitstreams: 1 komiyama_cm_me_botfmvz.pdf: 365903 bytes, checksum: 504da196f70e8cb733e0666e2460fef9 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / Foram realizados dois ensaios, sendo que o Ensaio 1 teve por objetivo avaliar as características de qualidade da carne de frangos de corte de coloração pálida e comparar com a de coloração normal e, o Ensaio 2, avaliar as diferenças sensoriais destes tipos de carnes. Para o Ensaio 1, foram coletados 52 filés pálidos e normais selecionados na linha de abate baseado pela sua coloração. Foi realizada a mensuração do pH, temperatura, cor e valor R nos tempos de zero, 4 e 24 horas post-mortem. As amostras foram encaminhadas ao laboratório da FMVZ/UNESP, campus de Botucatu e após 24 horas post-mortem procedeu-se as demais análises de qualidade de carne em que foram avaliadas as características de perda por exsudação, capacidade de retenção (CRA) e absorção de água, perdas de peso por cozimento (PPC) e força de cisalhamento. Para o Ensaio 2, foram coletados 40 filés pálidos e normais de abatedouro comercial, e após 24 horas post-mortem procedeu-se a avaliação das características sensoriais. Para os filés de peitos de frangos de coloração pálida, a glicólise teve inicio com o valor de pH 6,86 e atingiu pH final 5,73 às 24 horas post-mortem enquanto que os filés de peitos de coloração normal apresentaram pH inicial de 6,80 e pH 24 horas post-mortem de 5,85. Houve diferença significativa (p 0,05) entre os filés pálidos e normal para os parâmetros de pH, valor L*, teor de vermelho, CRA, PPC e desnaturação protéica.

Orientadores: Irenilza de Alencar Naas, Danilo Florentino Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-18T04:22:00Z (GMT). No. of bitstreams: 1 Nascimento_GuilhermeRodriguesdo_M.pdf: 1366852 bytes, checksum: 3be5b6e8ff020347c7de825f27df3e9e (MD5) Previous issue date: 2011 / Resumo: A produção de frangos de corte tem grande destaque na economia brasileira, sendo o país o terceiro maior produtor mundial e o principal exportador de carne de frangos. Um dos entraves da atividade é o estresse térmico ambiental, que impacta negativamente a produção. A pesquisa sugere que as temperaturas superficiais medidas com termografia em frangos de corte podem servir como base para inferir condições inadequadas de alojamento no ambiente de produção. O objetivo deste trabalho foi quantificar as temperaturas superficiais de frangos de corte em diferentes condições de alojamento, em ambiente controlado e no campo, e associar com condições do ambiente térmico. O experimento foi dividido em três etapas, na primeira foi analisada a variação da temperatura superficial média das aves em diferentes temperaturas do ar em câmara climática para diferentes idades. A segunda etapa foi realizada a campo em dois aviários, os quais foram registrados semanalmente os parâmetros ambientais internos e externos dos aviários e imagens termográficas da cama de frango, do forro e das membranas laterais (cortinas) associando com a temperatura superficial das aves. A eficiência térmica do alojamento foi feita comparando a perda de calor das aves nos dois aviários. Na terceira etapa foi proposto um índice Fuzzy de conforto térmico de frangos de corte com base na sua temperatura superficial. Com o auxílio da termografia foi possível calcular a temperatura superficial média de frangos de corte através da análise das imagens termográficas. Na análise termográfica a campo, concluiu-se que a temperatura superficial média de frangos de corte está mais associada à temperatura superficial do entorno de produção (cortinas laterais, forro e a cama de frango). Com base na variação da temperatura superficial média das aves utilizadas na pesquisa foi gerado o índice Fuzzy de conforto térmico (IFCT) que permite estimar condições de conforto térmico em condições tropicais, especifico na estimativa da condição de perigo térmico. A utilização das câmeras termográficas para aferição da temperatura superficial de frangos de corte pode ser utilizada para estimar condições de conforto térmico de frangos de corte em diferentes condições de alojamento / Abstract: The production of broiler chickens is of great importance in the Brazilian economy and the country is the third largest world producer and leading exporter of broiler meat. One problem in the activity is the environmental heat stress, which impacts negatively on production. This research suggests that the surface temperatures measured with thermography in broiler chickens may serve as a basis for inferring improper housing conditions in the production environment. The objective is to measure the surface temperatures of broilers in different housing conditions and associate with the weather. The experiment was divided into three stages: first, we analyzed the variation of mean surface temperature of the birds at different air temperatures and climate in the camera at different ages. The second stage was conducted in the field in two poultry houses in two different periods of accommodation, which were followed weekly by recording the climatic and environmental variables and the infrared thermographic images of poultry litter, and the membranes used in the sides, correlating it with the surface temperature of the birds, and the thermal efficiency of housing was done by comparing the heat loss of birds in two houses. In the third step it was proposed a fuzzy index of thermal comfort for broilers based on its surface temperature. With the aid of infrared thermal imaging it was possible to calculate the mean surface temperature of broilers by image analysis, without the need of using equations to estimate this. Using the infrared thermal image analysis conducted in the field, we conclude that the mean surface temperature of broiler chickens is more correlated to the surface temperature of the production environment (side curtains/ membranes, litter and chicken). Based on the variation of mean surface temperature of the birds used was generated Fuzzy index of thermal comfort (FITC) that allows estimating the thermal comfort in tropical conditions, to predict the specific condition of thermal hazard. The use of infrared technology to calculate the surface temperature of broilers, with the aid of thermographic cameras, gives out a basis for estimating the thermal comfort of broiler chickens in different housing conditions / Mestrado / Construções Rurais e Ambiencia / Mestre em Engenharia Agrícola

Orientador: Irenilza de Alencar Nääs / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-25T10:56:01Z (GMT). No. of bitstreams: 1 Neves_DiegoPereira_D.pdf: 2128104 bytes, checksum: aae1334cdaf344654741c087740bd7c6 (MD5) Previous issue date: 2014 / Resumo: Os frangos podem exibir diferentes padrões de movimentos biomecânicos as partes do corpo em relação às características físicas do alimento (tamanho, formato e dureza) durante a alimentação. As limitações anatômicas relacionadas com a idade, sexo e linhagem também podem afetar o processo mecânico de alimentação. Para determinar a importância desses parâmetros, as medidas relacionadas aos movimentos biomecânicos de partes corporais são necessárias. Em particular, a trajetória, dimensões e efeitos temporais relacionados com o bico do frango e com a movimentação da cabeça devem ser considerados. No entanto, determinar esta informação manualmente do vídeo por um operador humano é tedioso e propenso a erros. A presente tese tem como objetivo avaliar o impacto de três tipos distintos de ração sobre a biomecânica da alimentação de frangos de corte. O total de 19 pintos de corte machos foram filmados durante a alimentação aos 3 e 4 dias de idade através de uma câmera de alta velocidade com taxa de aquisição de 250 fps (quadros por segundo). As rações avaliadas foram: farelada fina (F1), farelada grossa (F2) e quebrada (F3), no qual o diâmetro geométrico médio e o desvio padrão geométrico foram 476?m (2.54), 638?m (2.56), e 1243?m (2.43) , respectivamente. O peso e a morfometria do bico (comprimento e largura) foram medidos após as gravações. O deslocamento da cabeça das aves durante as fases `mouthful¿ e `mandibulação¿ e a abertura máxima do bico foram mensurados por de análise computacional de imagem. A fase `mouthful¿ consistiu no movimento da cabeça de forma ininterrupta direção oblíqua ou vertical em direção à ração até que a partícula de alimento fosse capturada. A fase `mandibulação¿ consistiu em um ciclo de abertura e de fechamento do bico, na qual existe uma abertura máxima do bico. Estas fases foram classificadas manualmente como: `mouthful¿ como 'sucedido' ou 'fracassado' e `mandibulações¿ como `catch-and-throw¿ (CT) ou `slide-and-glue¿ (SG). O `mouthful sucedido¿ consistiu quando a ave capturou o alimento com sucesso, e a `mouthful fracassado¿ quando a ave errou a partícula de alimento. `Catch-and-throw¿ consistiu no reposicionamento da partícula na ponta bico antes de iniciar o transporte para o interior da cavidade oral. `Slide-and-glue¿ consistiu na deslocação da língua até a ponta em bico para aderir as partículas de alimento com o auxílio da saliva pegajosa e transportar para o interior da cavidade oral. Os resultados indicaram correlações significativas de fraca intensidade entre o peso, as características morfométricas do bico e as variáveis biomecânicas, bem como correlação entre a abertura máxima do bico e o deslocamento cabeça. O deslocamento da cabeça foi maior no `mouthful sucedido¿ (0,439 mm ± 0,002) em relação ao `mouthful fracassado¿ (0,371 mm ± 0,005). Além disso, o deslocamento da cabeça foi mais expressivo em F3 (0,526 mm ± 0,005), F2 (0,519 mm ± 0,004) e F1 (0,431 mm ± 0,003), respectivamente. O deslocamento da cabeça também foi significativamente maior para CT (0,245 mm ± 0,001) do que SG (0,114 mm ± 0,000). Considerando os diferentes tipos de ração, o deslocamento da cabeça para CT foi maior em F3, F1 e F2, enquanto que para SG foram maiores em F3, F2 e F1, respectivamente. A abertura máxima do bico também foi maior para CT (0,245 mm ± 0,001) do que SG (0,114 mm ± 0,00). Além do mais, para CT foi maior no F3 e F1 que em F2, enquanto que para SG foi maior para F1, F3 e F2, respectivamente. Assim, os diferentes tamanhos das partículas de ração (granulometria) foi, potencialmente, o fator chave para o movimento dos pintos durante a alimentação. Além disso, esta relação não foi proporcional à granulometria, explicada por valores mais elevados em F3 e F1. A ocorrência de `mouthful fracassado¿ foi 18,0% para F3, 11,2% para F2 e 6,6% para a F1. Para a classificação das mandibulações, observou-se a maior frequência de CT em F3 (26,1%), F1 (24,9%) e F2 (17,9%), respectivamente. Esta situação sugere que os pintos capturaram as partículas na ponta bico de maneira mais adequada para a deglutição com a granulometria 638µm (F2) do que 476?m (F1) e 1243µm (F3), explicada pela menor movimentação e necessidade de reposicionamento das partículas de alimento. De forma geral, a tecnologia de câmeras de alta velocidade combinada com análise computacional de imagem adotada neste experimento foi um método eficaz para análise de movimentação. É desejável uma melhor compreensão das limitações mecânicas do aparelho bucal das aves durante a alimentação, a fim de determinar a relação entre os diferentes tipos de alimentos sobre os padrões biomecânicas exibidos pelas aves / Abstract: Broiler chickens may exhibit different biomechanical motions patterns of the body parts in relation to the physical properties of feed (size, shape and hardness) while feeding. The anatomical limitations related to age, gender and breed may also impact the feeding mechanical process. To determine the significance of these parameters, measurements related to the biomechanical motions of body parts are required. In particular, the trajectory, dimensions and temporal effects related to the chicken¿s beak and head movements should be considered. However, determining this information manually from video by a human operator is tedious and prone to errors. The present thesis aims assess the impact of three different feed types on the biomechanics of feeding behaviour of broiler chicks. A total of 19 male broiler chicks were recorded while feeding at 3 and 4-d-old using a high-speed camera with an acquisition rate of 250 fps (frames per second). The feed types considered were: fine mash (F1), coarse mash (F2) and crumbled (F3), in which the geometric mean diameter and the geometric standard deviation were 476µm (2.54), 638µm (2.56), and 1243µm (2.43), respectively. The birds¿ weight and morphometric traits of the beak (length and width) were measured after the recordings. The birds¿ head displacement during mouthful and mandibulation phases and the maximum beak gape were measured through computational image analysis. Mouthful phase consisted an uninterruptedly head movement towards feed in an oblique or vertical direction until the feed particle is grasped. Mandibulation phase consisted in one cycle of opening and closing of the beak, in which there is a maximum beak gape. These phases were manually classified, as follows: mouthfuls as `normal¿ or `fail¿ and mandibulations as catch-and-throw (CT) or slide-and-glue (SG). Normal mouthful was when the bird successfully grasped the feed, and fail mouthful was when the birds missed the feed. Catch-and-throw is when the feed is repositioned within the beak tip before starting the transport into the oral cavity. Slide-and-glue consists in the displacement of the tongue up to the beak tip in order to glue the feed particles with the aid of the sticky saliva and carry inward oral cavity. The results indicated significant correlations of weak intensity between weight, morphometric traits of the beak, and the biomechanical variables, as well as correlation between maximum beak gape and head displacement. The head displacement was higher in a normal mouthful (0.439 mm ± 0.002) than fail mouthful (0.371 mm ± 0.005). Furthermore, head displacement was more expressive in F3 (0.526 mm ± 0.005), F2 (0.519 mm ± 0.004), and F1 (0.431 mm ± 0.003), respectively. The head displacement was also significantly higher for CT technique (0.245 mm ± 0.001) than SG (0.114 mm ± 0.000). Considering the different feed types, head displacement for CT was higher in F3, F1 and F2, while for SG were higher in F3, F2, and F1, respectively. The maximum beak gape was also higher for CT (0.245 mm ±0.001) than SG (0.114 mm ± 0.00). Moreover, for CT it was higher in F3 and F1 than in F2, while for SG was higher for F1, F3 and F2, respectively. Thus, the different size of the feed particles (granulometry) was potentially the key factor for the chicks¿ motion while feeding. Besides, this relation was not proportional to the granulometry, explained by higher values for F3 and F1. The occurrence of `fail mouthful¿ was 18,0% for F3, 11,2% for F2 and 6,6% for F1, respectively. For mandibulations classification, it was observed a higher frequency of CT in F3 (26,1%), F1 (24,9%), and F2 (17,9%). This situation suggests that the chicks grasped the particles in the beak tip more properly for swallowing with the granulometry 638µm (F2) than 476µm (F1), and 1243µm (F3), explained by the less motion and necessity of repositioning the feed particles. Overall, the high-speed camera technology combined with computational image analysis adopted in this experiment was an effective method for motion analysis. It is desirable a better understanding of the mechanical limitations of the birds¿ jaw apparatus while feeding in order to determine the relationship between different types of feed in biomechanical patterns displayed by the birds / Doutorado / Construções Rurais e Ambiencia / Doutor em Engenharia Agrícola

Master of Science / Department of Agricultural Economics / Vincent R. Amanor-Boadu / This study assessed the farm and farmer characteristics influencing the profitability of broiler chicken farms in Ghana. It used data obtained from the 2015 census of the poultry industry conducted by USAID-METSS in collaboration with Ghana's Ministry of Food and Agriculture and the Ghana National Association of Poultry Farmers. Results show that broiler production in Ghana is operated on a small scale basis with an average number of 1,410 birds. Broiler chicken production is profitable in Ghana with national average gross margin/bird of GHS 9.22 and standard deviation of 8.40. Regression analysis was carried out using Ordinary Least Square method to estimate the effect of farm and farmer characteristics on profitability and also explore regional differences. Results shows that farm income and feed were negative and statistically significant such that a farmer with primary income from broiler chicken production had a decrease in gross margin of GHS 1.24 per bird compared to a farmer with other sources of income; a farmer that increases one unit of own feed production will have a decrease in gross margin of GHS 0.06 per bird. Additionally, regional differences exist such that farms situated in Ashanti, Central, and Eastern had higher gross margin per bird of GHS 3.21, GHS 6.10 and GHS 6.26 respectively compared to farms situated in Brong Ahafo Region. In conclusion, the study shows that both farmer (primary source of income) and farm characteristics (such as regional location and the extent to which feed was prepared on the farm) were important in explaining broiler chicken profitability. Finally, continuous research is recommended to examine the robustness of these factors in explaining profitability.

The objective of the experiments conducted for this dissertation was to determine the standardized ileal digestibility (SID) of amino acids (AA) in a variety of feed ingredients for broiler chickens and pigs. The effects of casein in experimental diets on the SID of AA in corn distillers’ dried grains with solubles (DDGS) fed to pigs were evaluated. The SID of AA in feed ingredients, which include full-fat soybean (FFSB), two soybean meals (SBM), peanut flour (PNF), full-fat canola seeds (FFCS), canola meal (CM), canola expellers (CE), hydrolyzed feather meal (HFM), flash dried poultry protein (FDPP), poultry meal (PM), and meat and bone meal (MBM), were compared in broiler chickens and pigs. One of the studies determined the ileal digestibility of AA in casein by regression analysis and investigated the effects of 60 g/kg casein in experimental diets on the SID of AA in DDGS. The ileal digestibility of AA in casein were close to 100%, ranging from 95.5% (SE = 9.10) for Cys to 103.1% (SE = 4.40) for Arg. In addition, the SID of Lys and Phe in DDGS determined by pigs fed the diet containing DDGS and casein were greater (<i>P</i> < 0.05) than the values determined by pigs fed the diet containing DDGS without casein. Based on the results of this experiment, two additional experiments were conducted to determine the effects of graded concentrations of casein from 55 to 165 g/kg in experimental diets on the SID of AA in DDGS and to determine the effects of dietary DDGS concentrations (i.e., 155.6 or 466.8 g/kg) and addition of casein in experimental diets on the SID of AA in DDGS. The SID of indispensable AA, except for Arg and Lys, linearly decreased (<i>P</i> < 0.05) as the concentration of casein in experimental diets increased. Moreover, pigs fed the diets containing 155.6 g/kg DDGS had less (<i>P</i> < 0.05) SID of indispensable AA, except for Trp, in DDGS than those fed the diets containing 466.8 g/kg DDGS regardless of the addition of casein in experimental diets. Therefore, it may be concluded that the addition of casein improves the SID of AA in DDGS, but reduced DDGS concentration in experimental diets decreases the SID of AA in DDGS. In one pair of experiments conducted to compare the SID of AA in FFSB, SBM containing 430 g/kg crude protein, SBM containing 470 g/kg crude protein, and PNF between broiler chickens and pigs, the SID of AA, except for Trp, Ala, and Glu, in test ingredients for pigs were greater (<i>P</i> < 0.05) than the values for broiler chickens. In addition, in both broiler chickens and pigs, the SID of Ile, Leu, and Val in FFSB were less (<i>P</i> < 0.05) than in the other test ingredients. In another pair of experiments conducted to compare the SID of AA in FFCS, CM, and CE between broiler chickens and pigs, interactions (<i>P</i> < 0.05) between experimental diets and species were observed in the SID of AA, except for Lys, Gly, Pro, and Ser. The SID of AA in FFCS for broiler chickens were greater (<i>P</i> < 0.05) than pigs; however, there was no difference in the SID of AA in CM or CE between broiler chickens and pigs. The objective of a third pair of experiments was to compare the SID of AA in HFM, FDPP, PM, and MBM fed to broiler chickens and pigs. There were interactions (<i>P</i> < 0.05) between experimental diets and species in the SID of His, Thr, Trp, and Val. In broiler chickens, the SID of His, Thr, and Trp in FDPP and PM were greater (<i>P</i> < 0.05) than in HFM but were less (<i>P</i> < 0.05) than MBM; however, difference in SID of His, Thr, and Trp among FDPP, PM, and MBM was not observed in pigs. Based on the results of three pairs of studies, it was revealed that differences in SID of AA in common feed ingredients for both broiler chickens and pigs were affected by species. Therefore, it may be concluded that the effects of feed ingredient-specific factors on the SID of AA are different between broiler chickens and pigs.