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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.
1

Genetics, humoral immunoresponsiveness, and disease resistance in chickens

Boa-Amponsem, Kwame Jr. 08 July 1998 (has links)
Lines of White Leghorn chickens selected > 20 generations for (HA) and against (LA) antibody response to SRBC injected i.v. from 41 to 51 days of age, are now known to have diverged in primary antibody response to SRBC. Experiments described in this dissertation were designed to further evaluate the immune competence of these lines as influenced by age, diet, and a disease agent. A crossing experiment was also conducted to further describe the mode of inheritance of such competence. Humoral immunocompetence was evaluated by primary, memory, and maternal antibody responses to SRBC. Primary antibody response, measured 5, 10, and 20 days after inoculation with SRBC was greater in HA than LA chicks inoculated at 14, 21, and 28 days of age. In chicks injected at 7 days of age, a higher frequency of responders was observed for HA than LA chicks suggesting an earlier onset of immunocompetence in the high than low antibody line. Immunological memory antibody responses (secondary and tertiary) was studied in parallel experiments on two groups of chicks hatched at a 14-day interval. Chicks in both hatches were from the same matings of parental Lines HA and LA. Memory responses were evident in chicks at 14 days of age. Antibody responses to a second and third inoculation with SRBC were similar for both lines suggesting that genetic factors that influence primary and memory responses are not the same. The responses of LA chicks to repeat inoculations with SRBC were anamnestic whereas those of HA chicks initially inoculated at 28 days of age were not anamnestic. This study did not establish any major influence of nutrient density on either primary or memory immune responses even though the higher nutrient density diet improved growth performance. Assays in chicks indicated that maternal antibodies were transferred earlier into eggs laid by HA hens than in those of LA hens ( 7 to 9 days vs 10 to 12 days after inoculation) regardless of dosage administered. Response patterns whether assessed in terms of frequency of detection or magnitude of response showed divergence between the lines. Chicks of parental, reciprocal F , F , and backcrosses of 1 2 mating combinations of Lines HA and LA were injected with SRBC at 36 days of age. Contrasts between parental lines for antibody titers measured 5 and 12 days later showed higher antibody titers in HA than LA chicks. Sex-linked effects were evident because reciprocal contrasts for F crosses, individual heterosis, and 1 maternal heterosis were sex dependent. Response to marble spleen disease virus ( MSDV) measured 6 days after inoculation of chicks from parental, reciprocal F1, F2, and backcross matings of the lines, indicated that the mode of inheritance of spleen weight differed after infection. In the infected chicks, parental contrasts for absolute and relative spleen weights showed greater resistance to MSDV in LA than HA chicks. No other genetic effect was consistently important after infection. / Ph. D.
2

Reproductive Soundness and Egg Quality in Chickens Selected for Low and High Antibody Response

Albrecht, Heather Nicole 08 September 2011 (has links)
For 36 generations, White Leghorn chickens were selected for high (HAS) or low (LAS) antibody response to sheep red blood cells. The focus of this thesis was to investigate correlated responses in reproductive soundness and egg quality resulting from that selection. Forty-five hens and 25 roosters from each antibody line were used. In hens, commencement and intensity of lay, and egg quality, were analyzed; in both sexes, length of fertility was considered. Hens and roosters were mated to an intercross line to avoid confounding selection with sex effects. The LAS line was more reproductively sound, commencing lay at a younger age (11.67 ± 3.53 d; P < 0.001), lighter body weight (-169.46 ± 40.20 g; P < 0.001) and with greater intensity (2.68 ± 0.25%; P = 0.001) than the HAS line. Additionally, the LAS line had a greater length of fertility (hens: 2.43 ± 0.55 d; P < 0.001; roosters: 3.11 ± 0.71 d; P < 0.001). In contrast to their poorer reproductive soundness, the HAS line had superior egg quality compared to the LAS line. Egg shape index (4.12 ± 0.55; P < 0.001) and albumen height, measured in both mm (0.27 ± 0.12 mm; P < 0.001) and Haugh units (1.89 ± 0.91; P = 0.04), were superior in HAS hens. Selection for increased antibody response appeared to compromise reproductive soundness, perhaps due to limitations in available resources. However, the selection did not compromise egg quality. / Master of Science
3

Efeito do suco de caju (Anacardium occidentale L.) adicionado de farinhas do bagaÃo de caju sobre a resposta imunolÃgica em camundongos / Effect of cashew apple juice (Anacardium occidentale L.) added to flour from crushed cashews on the immune response in mice

Camila Freitas Bezerra 26 February 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O caju e a castanha, pseudofruto e fruto do cajueiro (Anacardium occidentale L.), apresentam alto valor nutricional, porÃm menos de 10% do pedÃnculo proveniente do beneficiamento da castanha sÃo aproveitados. Uma alternativa para o aproveitamento do bagaÃo de caju seria seu processamento em farinha, a qual poderia ser adicionada ao suco de caju e assim aumentar suas propriedades nutricionais. O objetivo do trabalho foi avaliar a composiÃÃo fitoquÃmica, o potencial antioxidante total e a atividade imunomoduladora do suco de caju adicionado com farinha do bagaÃo de caju maduro (SFM) e verde (SFV). Para tanto, avaliou-se a capacidade antioxidante do suco e das farinhas de caju (clone CCP-76) por dois mÃtodos, ABTS e DPPH. Os compostos fitoquÃmicos determinados foram os polifenÃis, vitamina C, carotenoides, antocianinas e flavonoides amarelos. Os testes in vivo foram realizados com camundongos Swiss machos, provenientes do BiotÃrio Central da UFC. O protocolo experimental foi aprovado pelo Comità de Ãtica em Pesquisa com Animal da UFC (N 102/2011). Para os ensaios toxicolÃgicos, camundongos foram tratados por 19 dias, por via oral, com diferentes doses de SFM e SFV e os parÃmetros fisiolÃgicos como peso do animal, peso relativo dos ÃrgÃos, peroxidaÃÃo lipÃdica e dosagem das enzimas ALT e AST foram determinados. Para avaliaÃÃo da resposta imune humoral e celular, os animais foram imunizados com hemÃcias de carneiro (HC) para determinar o tÃtulo de anticorpos pelo mÃtodo de hemaglutinaÃÃo e posteriormente desafiados com HC, para avaliar a resposta de hipersensibilidade tardia (DTH). Para verificar as diferenÃas significativas entre as mÃdias dos diferentes grupos, aplicou-se o teste ANOVA seguido de Tukey ou Newman-Keuls, considerando as diferenÃas significativas quando p < 0,05. A farinha verde de bagaÃo de caju apresentou a maior capacidade antioxidante e os maiores teores de polifenÃis, constituinte predominante tambÃm na farinha de caju maduro e no suco. NÃo se constatou alteraÃÃes significativas em nenhum parÃmetro avaliado no ensaio toxicolÃgico. Na resposta humoral, o suco de caju e o SFV na dose de 300 mg/kg apresentaram os maiores tÃtulos de anticorpos com aumento de 120,69 e 100% em relaÃÃo ao controle. Jà na resposta celular, o suco, SFM e SFV (dose de 300 mg/kg) induziram um aumento na DTH de 10,66; 10,66 e 11,11%, respectivamente, em relaÃÃo ao controle. O suco adicionado da farinha do bagaÃo do caju em diferentes estÃdios de maturidade pode ser uma alternativa para melhoria da resposta imunolÃgica. No entanto, sÃo necessÃrios estudos complementares para viabilizar essa suplementaÃÃo do suco com as farinhas. / The cashew apple and cashew nut, pseudo fruit and fruit (Anacardium occidentale L.) have high nutritional value, but less than 10% of the cashew apple from the processing of cashew nut is availed. The cashew apple juice added with bagasse flour could therefore be an alternative for the improvement of its nutritional properties. The aim of this study was to evaluate the phytochemical composition, the total antioxidant potential and immunomodulatory activity of cashew apple juice with added of the flour mature bagasse (CAJM) and immature (CAJIM) of the cashew apple. Therefore, we evaluated the antioxidant capacity of juice and flour of cashew apple (clone CCP-76) by two methods, ABTS and DPPH. The phytochemicals compounds quantified were polyphenols, vitamin C, carotenoids, anthocyanins and flavonoids yellow. In vivo tests were performed with male swiss mice, from the animal colony of UFC, with approval by the Ethics Committee on Animal Research (CEPA) under the UFC protocol No. 102/2011. Toxicity tests were carried out on mice treated for 19 days orally with CAJM and CAJIM at different doses. Physiological parameters such as body weight, relative organ to body weight, lipid peroxidation and dosage of the ALT and AST enzymes were determined. To evaluate the humoral and cellular immune response, the treated animals were immunized with sheep red blood cells (SRBC) to determine the antibody titer by hemagglutination method and later challenged with (SRBC) to evaluate the delayed type hypersensitivity (DTH) reaction. To analyze the significant differences between the means of different groups, we applied the ANOVA followed by Tukey or Newman-Keuls and differences were considered significant at p < 0.05. Flour Cashew green bagasse showed the highest antioxidant capacity and the highest levels of polyphenols, also predominant constituent in flour and ripe cashew juice. The ripe flour showed the highest antioxidant capacity and the highest levels of polyphenols, also predominant constituent in ripe flour and cashew apple juice. There were no significant changes in any parameters evaluated in toxicity test. In the humoral response, the cashew apple juice and CAJIM at dose of 300 mg / kg showed higher antibody titer with an increase of 120.69 and 100.00 % compared to the control group. Already in cellular response, juice, SFM and SFV (300 mg / kg) induced an increase in DTH of 10.66, 10.66 and 11.11% respectively, compared to control. The cashew apple juice added with the flour of cashew bagasse in stages of maturity different can be an alternative for improving the immune system. However, further studies are needed to enable this supplementation of juice with flours.
4

Genomics-Based Analysis of Antibody Response to Sheep Red Blood Cells in Chickens

Geng, Tuoyu 01 June 2007 (has links)
Immune response provides vertebrates an important mechanism to fight pathogens and to reduce the incidence of diseases. Defining the molecular basis of antibody response may facilitate genetic improvement in the immune response of animals to pathogens. For almost 4 decades, antibody titers in response to challenge by sheep red blood cells (anti-SRBC) have provided an investigative tool in the efforts to define molecular mechanisms that underlie vertebrate immune response. The overall objective of this dissertation research was to identify DNA markers associated with anti-SRBC response in chickens. Specific objectives were: to develop a resource population for QTL analysis for anti-SRBC, to identify DNA markers and genes associated with primary anti-SRBC, and to evaluate the allelic frequencies in non-selected chicken populations of candidate markers associated with either high or low anti-SRBC response. These objectives tested the hypothesis that genetic control of a chicken's response to SRBC is polygenic. The resource population developed consisted of F1, backcross, and F2 derived from reciprocal crosses of birds from parental lines in the 28th generation of divergent selection for low (L) and high (H) anti-SRBC. The mean anti-SRBC titers of the parental lines were significantly different, with 11.5 for H and 2.6 for L (P<0.05). That for the 4 groups of F2 progeny ranged from 6.3 to 7.5, while those of the 8 groups of backcross progeny ranged from 3.9 to 13.3. Four of 555 random primers used to screen the parental H and L anti-SRBC lines were informative by amplifying seven line-specific fragments (P<0.0025). Each of the 7 line-specific fragments was converted to a sequence characterized amplified region (SCAR) within which single nucleotide polymorphisms (SNPs) were identified and tested for association with anti-SRBC. Only two of the seven SCARs in the parental lines were associated (P<0.05) with anti-SRBC level in the backcross resource population. Additionally, from analysis of the parental L and H anti-SRBC lines using microarrays, a total of 57 line-specific SNPs were also identified. Twenty of the line-specific SNPs were in and/or near genes previously reported to have immunity-related function. Microarray-based gene expression profiling of pooled RNA samples from L and H anti-SRBC birds identified three differentially expressed genes. In summary, this dissertation describes resources that include candidate SCARs and SNPs as well as differentially expressed genes that may be useful for the identification of genes that underlie antibody response. / Ph. D.

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