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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.
111

Effects of ammonium perchlorate exposure on the thyroid function and the expression of thyroid-responsive genes in Japanese quail embryos and post hatch chicks

Chen, Yu 05 August 2008 (has links)
Perchlorate ion interferes with thyroid function by competitively inhibiting the sodium-iodide symporter, thus blocking iodide uptake into the thyroid gland. In this study, the effect of perchlorate exposure on thyroid function and thyroid-responsive gene expression were examined in (1) embryos from eggs laid by perchlorate-treated Japanese quail hens and (2) perchlorate-treated young Japanese quail. I hypothesized that perchlorate exposure would decrease thyroid function and that the consequent hypothyroidism would alter the expression of thyroid sensitive genes. Laying Japanese quail hens were treated with 2000 mg/l and 4000 mg/l ammonium perchlorate in drinking water. Eggs from these hens were incubated. Embryos, exposed to perchlorate in the egg, were sacrificed at day 14 of the 16.5 day incubation period. Japanese quail chicks, 4-5 days old, were treated with 2000 mg/l ammonium perchlorate in drinking water for 2 and 7.5 weeks. Thyroid status was evaluated by measuring plasma thyroid hormone concentrations, thyroid gland weight and thyroidal thyroid hormone storage. Expression of thyroid-responsive genes was evaluated by measuring the mRNA levels of Type 2 deiodinase (D2) in the brain and liver, RC3/neurogranin mRNA level in the brain and Spot 14 mRNA level in the liver. Maternal perchlorate exposure led to embryonic hypothyroidism, demonstrated by thyroid hypertrophy and very low embryonic thyroidal TH storage. Embryonic hypothyroidism decreased body growth and increased D2 mRNA level in the liver (a presumed compensatory response to hypothyroidism) but did not affect the mRNA levels of D2 and RC3 in the brain. Spot 14 mRNA was not detected in embryonic liver. In the second part of the study, quail chicks showed early signs of hypothyroidism after two weeks of 2000 mg/l ammonium perchlorate exposure; plasma concentration and thyroid gland stores of both T4 and T3 were significantly decreased. After 7.5 weeks of perchlorate exposure, all thyroid variables measured indicated that the chicks had become overtly hypothyroid. D2 mRNA level was increased, a compensatory response to hypothyroidism, and spot 14 mRNA level was decreased, a substrate-driven response in the liver of quail chicks after two weeks of perchlorate exposure. However, no difference was observed in the mRNA levels of D2 and spot 14 in the liver after 7.5 weeks of perchlorate exposure, suggesting there was some adaptation to the hypothyroid condition. The mRNA level of D2 and RC3 in the brain was not affected by perchlorate-induced hypothyroidism in quail chicks after either 2 or 7.5 weeks of perchlorate exposure. As in the embryos, this suggests the brain of chicks was "protected" from the hypothyroid body conditions. / Ph. D.
112

Contaminants at a Shooting Range: Toxicological and Nutritional Significance to Birds and Mammals

Gonzalez, Gabriela Rae 25 August 2003 (has links)
Target shooting in the United States has become an increasingly popular sport in the last century. In addition to the large quantity of lead pellets littering range grounds and surrounding land, considerable amounts of clay target fragments cover shooting range areas as well as adjoining habitats. Polycyclic aromatic hydrocarbons (PAHs) within the target, as well as lead pellets from shotguns pose multiple threats to a variety of wildlife. To determine the effects of clay target and lead pellet ingestion on wildlife, I conducted controlled experiments on Coturnix quail exposed to clay targets in the lab, and collected wild birds and mammals exposed to lead pellets at a shooting range. The first Coturnix study determined whether quail voluntarily consumed target fragments or limestone fragments. In both fall (F=29.2, P<0.01) and spring (F=6.45, P=0.02) experiments, I found that quail consistently selected limestone fragments, but almost completely rejected clay target fragments. In the second study, quail were force-fed varying amounts of target dust on a weekly basis to simulate sporadic exposure to clay target dust. In both summer (F=1.63, P=0.23) and winter (F=0.34, P=0.8) trials, male quail did not have significant weight loss. Female quail had insignificant weight losses in summer trials (F=1.63, P=0.23) but experienced weight gains in winter trials (F=3.53, P=0.04). In the third and final Coturnix study, varying amounts of target dust were incorporated into daily feed rations to simulate frequent exposure to clay target dust. Male quail experienced weight loss in both summer (F=16.13, P<0.01) and winter (F=8.47, P<0.01) trials. Female quail also suffered weight loss in both summer (F=15.62, P<0.01) and winter (F=17.50, P<0.01) trials. Weight loss likely resulted from inadequate nutrition as opposed to target poisoning. However, because there were no biochemical analyses performed to test for PAH presence, no definite conclusions can be made. The second study focused on lead contamination in Passeriformes, perching birds, and small mammals. Seventeen of 20 birds (85%) (Passerine spp) captured at the shooting range had elevated lead levels (F=5.21, P<0.028), when compared to birds (n=20) at the control site. Nine of 26 (35%) white-footed mice (Peromyscous leucopus), trapped at the shooting range had elevated liver (F=9.78, P=0.0029) and kidney (F=22.49, P<0.01) lead levels. These results indicate that Passerine species as well as Peromyscous species around shooting ranges inadvertently consume lead, either as lead pellets, mistaking them for grit or dietary items, or through environmental sources such as water, soil, and vegetation. / Master of Science
113

Uridinediphosphate-glucuronosyltransferase (UDP-GT) Ontogeny and PCB Effects in Galliform Birds

McCleary, Ryan J. R. 06 December 2001 (has links)
Hepatic UDP-GTs are partly responsible for metabolism of the thyroid hormone, thyroxine (T4), in mammals, but little is known of UDP-GT activity in birds. To determine the ontogenic pattern of UDP-GT activity in precocial birds, we measured activity in Japanese quail (Coturnix japonica) liver at days 12 and 14 of the 16.5-day incubation, 3 perihatch stages and <1, 1, 4, 6, 7, 20 and 42 days posthatch. We used an enzymatic reaction with para-nitrophenol (pNP) as substrate that was validated for quail tissue. The pattern of UDP-GT development included low embryonic activity, increased activity beginning in the perihatch period, a peak in activity at day 4 posthatch and a return to lower activity levels from day 6 to adults. The profile of UDP-GT activity, in relation to the ontogeny of circulating T4 and triiodothyronine (T3) in quail, is consistent with UDP-GT playing a role in regulating circulating T4 and with the perihatch peak in T3 stimulating the posthatch peak in UDP-GT activity. To examine the effects of polychlorinated biphenyls (PCBs) on UDP-GT in developing precocial birds, we dosed chicken (Gallus domesticus) eggs with concentrations of PCB 126 from 0 to 0.80 ng/g egg (in sunflower oil) prior to incubation. Tissues were sampled at day 20 of the 21-day incubation and assayed for plasma hormones and UDP-GT activity. Eggs also were dosed with 0 or 0.25 ng PCB 126/g egg or with 0 or 0.64 ng/g egg of the coplanar PCB 77, allowed to hatch, and sampled at 42 days posthatch. There was no consistent pattern of altered thyroid hormones or UDP-GT activity in developing chickens exposed to either of these coplanar PCBs although previous studies indicated developmental alterations from exposure to the higher doses. / Master of Science
114

Imunnoresponsiveness in Japanese quail and chickens

Miller, Libbie L. 07 April 2009 (has links)
The association between selection for body weight and immune responsiveness was studied in Japanese quail and White Plymouth Rock chicken populations. Quail populations consisted of a randombred control (C) line and a line selected for high (HW) 28-day body weight. The chicken populations used were lines selected for high (HW) and low (LW) 56-day body weight, reciprocal Fi crosses (HL and LH), and F2 crosses of the Fi (HLHL and LHLH). Kinetics of primary and secondary antibody response to SRBC antigen was examined in Line C quail (Experiment 1). At most times post-primary inoculation (PPI), antibody titers were highest for antigen concentration 2.5%. The presence of MER antibodies was very low PPI, but increased following reinjection. Primary antibody response was then compared between C line and HW line of quail (Experiment 2). Antigen concentration 2.5% once again resulted in the highest titers. Line HW quail were less able to maintain high antibody titer levels to SRBC antigen than the randombred control line from which they originated. Mode of inheritance for immune responsiveness in selected populations of chickens and crosses between them was examined (Experiment 3). Additive genetic variation was important in the inheritance of both primary and secondary responses to this antigen. Reciprocal differences and heterosis of the F₁ crosses were also factors in the inheritance of secondary response. Kinetics of primary and secondary responses were evaluated in the parental weight lines and in lines of White Leghorn chickens divergently selected for antibody response to SRBC antigen. At all times PPI, line HA chickens had the highest antibody titers, while those from line LA consistently had the lowest titers. Lines HW and LW reacted similarly to line LA early in response, but showed higher peak levels later on. In both primary and secondary responses, the weight lines peaked at similar levels. Thereafter, line LW maintained a high antibody titer level to SRBC antigen than line HW. / Master of Science
115

Análise proteômica dos ovos de codorna não fertilizados em diferentes tempos e temperaturas de estocagem / Proteomic analysis of quail eggs unfertilized at different times and storage temperatures

Aquino, Adriano 12 June 2015 (has links)
O uso de codornas japonesas (Coturnix coturnix japonica) como modelo animal para estudos relacionados a indústria avícola está crescente em decorrência do aumento no consumo de carne e ovos. O ovo possui várias aplicações e a sua funcionalidade está correlacionada com a composição química e, mais especificamente, com seu alto valor proteico. Contudo, o ovo é um alimento altamente perecível, pois pode perder sua qualidade rapidamente entre o período de estocagem e consumo. A qualidade do ovo pode ser afetada por condições ambientais como tempo e temperatura de estocagem. Parâmetros convencionais como pH, massa e a unidade Haugh são usados para a avaliação da qualidade do ovo. Além disso, técnicas analíticas podem ser utilizadas para a avaliação de qualidade em diversas matrizes alimentares. Assim, o presente trabalho tem como objetivos a avaliação e identificação de proteínas presentes em ovos de codorna japonesa submetidos a diferentes tempos e temperaturas de estocagem empregando técnicas eletroforéticas e espectrometria de massas, além de, ferramentas estatísticas. Durante estocagem à 0-21 dias, observou um aumento no pH, diminuição na massa do ovo e uma mudança significativa no proteoma das amostras nos períodos de 14 a 21 dias. Além disso, os resultados de análise de componentes principais (PCA) demostraram a influência da temperatura pela formação de 4 grupos independentes para amostras de albúmen e 3 grupos para as amostras de plasma e fração granular, respectivamente. Para o plasma, as amostras estocadas à 25 °C e controle se agruparam. Já para a fração granular, o agrupamento ocorreu entre as amostras estocadas a 25 °C com a 37 °C, demonstrando similaridade entre si. As proteínas com os níveis significativamente (p &lt;0.05) alterados durante a estocagem pertencem as famílias serpina (ovalbumina), transferrina (ovotransferrina), inibidores Kazal tipo de protease (ovoinibidor). Para a ovotransferrina, proteína encontrada em todas as amostras foi observado a formação de isoformas no albúmen, plasma e fração granular nas amostras estocadas a 37 °C, sendo um bom indicador de controle de qualidade. Por fim, para as amostras de albúmen fracionadas por OFFGEL e analisadas por 1D-PAGE foi observado a formação de isoformas tanto para a ovalbumina quanto para a ovotransferrina bem como a degradação de ovoinibidor nas amostras estocadas por 21 dias a 37 °C, fatos que podem estar associados ao desbaste. Esses eventos afirmam a influência do tempo e temperatura de estocagem na qualidade do ovo de codorna. / The use of Japanese quail (Coturnix coturnix japonica) as animal model for studies related to the poultry industry is becoming more common due to the increased consumption of meat and eggs. The egg has a variety of applications and its functionality is correlated to the chemical composition and, more specifically, its high protein value. However, the egg is a highly perishable food, and it can lose its quality between the period of storage and consumption. The egg quality can be affected by environmental conditions such as storage time and temperature. Conventional parameters such as pH and Haugh unit mass are used for egg quality assessment. Furthermore, analytical techniques can be used for quality assessment in various food matrices. This study aims to review and to identify proteins present in Japanese quail eggs submitted at different times and storage temperatures using electrophoretic techniques and mass spectrometry techniques, as well as statistical tools. During storage at 0-21 days, observed an increase in pH, decrease in egg mass and a significant change in the proteome of samples during the 14 to 21 day period. Moreover, the principal component analysis results (PCA) have shown the influence of temperature because of the formation of the four groups to albumin samples and three groups for the plasma and granules fraction samples, respectively. In plasma, the samples stored at 25 ° C and clustered control. As for the granule fraction pooling occurred between samples stored at 25 ° C to 37 ° C, showing similarities among them. The proteins with significant levels (p &lt;0.05) of change during the storage belong to serpin family (albumin), transferrin (ovotransferrin), Kazal type protease inhibitors (ovoinhibitor). Ovotransferrin, a protein isoform found in albumin, plasma and granules fraction samples and was observed the formation of more isoforms in samples stored at 37 ° C, a good to quality control lost indicator. Finally, for the albumen samples that were fractionated by OFFGEL and analyzed by 1D-PAGE, the formation of both isoforms to ovalbumin was observed as well as ovotransferrin and ovoinhibitor degradation in samples stored for 21 days at 37 ° C that can be associated to thinning. These events affirm the influence of time and storage temperature on quail egg quality.
116

Análise proteômica dos ovos de codorna não fertilizados em diferentes tempos e temperaturas de estocagem / Proteomic analysis of quail eggs unfertilized at different times and storage temperatures

Adriano Aquino 12 June 2015 (has links)
O uso de codornas japonesas (Coturnix coturnix japonica) como modelo animal para estudos relacionados a indústria avícola está crescente em decorrência do aumento no consumo de carne e ovos. O ovo possui várias aplicações e a sua funcionalidade está correlacionada com a composição química e, mais especificamente, com seu alto valor proteico. Contudo, o ovo é um alimento altamente perecível, pois pode perder sua qualidade rapidamente entre o período de estocagem e consumo. A qualidade do ovo pode ser afetada por condições ambientais como tempo e temperatura de estocagem. Parâmetros convencionais como pH, massa e a unidade Haugh são usados para a avaliação da qualidade do ovo. Além disso, técnicas analíticas podem ser utilizadas para a avaliação de qualidade em diversas matrizes alimentares. Assim, o presente trabalho tem como objetivos a avaliação e identificação de proteínas presentes em ovos de codorna japonesa submetidos a diferentes tempos e temperaturas de estocagem empregando técnicas eletroforéticas e espectrometria de massas, além de, ferramentas estatísticas. Durante estocagem à 0-21 dias, observou um aumento no pH, diminuição na massa do ovo e uma mudança significativa no proteoma das amostras nos períodos de 14 a 21 dias. Além disso, os resultados de análise de componentes principais (PCA) demostraram a influência da temperatura pela formação de 4 grupos independentes para amostras de albúmen e 3 grupos para as amostras de plasma e fração granular, respectivamente. Para o plasma, as amostras estocadas à 25 °C e controle se agruparam. Já para a fração granular, o agrupamento ocorreu entre as amostras estocadas a 25 °C com a 37 °C, demonstrando similaridade entre si. As proteínas com os níveis significativamente (p &lt;0.05) alterados durante a estocagem pertencem as famílias serpina (ovalbumina), transferrina (ovotransferrina), inibidores Kazal tipo de protease (ovoinibidor). Para a ovotransferrina, proteína encontrada em todas as amostras foi observado a formação de isoformas no albúmen, plasma e fração granular nas amostras estocadas a 37 °C, sendo um bom indicador de controle de qualidade. Por fim, para as amostras de albúmen fracionadas por OFFGEL e analisadas por 1D-PAGE foi observado a formação de isoformas tanto para a ovalbumina quanto para a ovotransferrina bem como a degradação de ovoinibidor nas amostras estocadas por 21 dias a 37 °C, fatos que podem estar associados ao desbaste. Esses eventos afirmam a influência do tempo e temperatura de estocagem na qualidade do ovo de codorna. / The use of Japanese quail (Coturnix coturnix japonica) as animal model for studies related to the poultry industry is becoming more common due to the increased consumption of meat and eggs. The egg has a variety of applications and its functionality is correlated to the chemical composition and, more specifically, its high protein value. However, the egg is a highly perishable food, and it can lose its quality between the period of storage and consumption. The egg quality can be affected by environmental conditions such as storage time and temperature. Conventional parameters such as pH and Haugh unit mass are used for egg quality assessment. Furthermore, analytical techniques can be used for quality assessment in various food matrices. This study aims to review and to identify proteins present in Japanese quail eggs submitted at different times and storage temperatures using electrophoretic techniques and mass spectrometry techniques, as well as statistical tools. During storage at 0-21 days, observed an increase in pH, decrease in egg mass and a significant change in the proteome of samples during the 14 to 21 day period. Moreover, the principal component analysis results (PCA) have shown the influence of temperature because of the formation of the four groups to albumin samples and three groups for the plasma and granules fraction samples, respectively. In plasma, the samples stored at 25 ° C and clustered control. As for the granule fraction pooling occurred between samples stored at 25 ° C to 37 ° C, showing similarities among them. The proteins with significant levels (p &lt;0.05) of change during the storage belong to serpin family (albumin), transferrin (ovotransferrin), Kazal type protease inhibitors (ovoinhibitor). Ovotransferrin, a protein isoform found in albumin, plasma and granules fraction samples and was observed the formation of more isoforms in samples stored at 37 ° C, a good to quality control lost indicator. Finally, for the albumen samples that were fractionated by OFFGEL and analyzed by 1D-PAGE, the formation of both isoforms to ovalbumin was observed as well as ovotransferrin and ovoinhibitor degradation in samples stored for 21 days at 37 ° C that can be associated to thinning. These events affirm the influence of time and storage temperature on quail egg quality.
117

Padronização de técnicas de diagnóstico em virologia utilizando ovos embrionados de codorna como modelo biológico / Standardization in virology diagnostic techniques using embryonated quail eggs as the biological model

Lobo, Raulene Rodrigues 27 February 2015 (has links)
Submitted by Ubirajara Cruz (ubirajara.cruz@gmail.com) on 2017-05-12T16:34:54Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Raulene_Lobo.pdf: 1126014 bytes, checksum: 21add1be01d589b0f84ebea48c02f60d (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-05-12T21:23:08Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Raulene_Lobo.pdf: 1126014 bytes, checksum: 21add1be01d589b0f84ebea48c02f60d (MD5) / Made available in DSpace on 2017-05-12T21:23:08Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Raulene_Lobo.pdf: 1126014 bytes, checksum: 21add1be01d589b0f84ebea48c02f60d (MD5) Previous issue date: 2015-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Os ovos embrionados de codorna podem ser utilizados para inoculação de diversos tipos de vírus, por diferentes vias, assim como técnicas já conhecidas e aplicadas em ovos embrionados de galinha (Gallus domesticus) com algumas adequações. Podem ser atribuídas vantagens a esse processo, tais como: custo menor de produção, redução do tempo de incubação, necessidade de menor espaço físico e, talvez a mais importante, ser de uma espécie diferente do Gallus domesticus e desta forma não ser portadora de antígenos e anticorpos de interesse na avicultura comercial moderna, não interferindo no diagnóstico e na replicação viral. Para avaliar o potencial de replicação viral, foram utilizados 351 ovos embrionados de codorna de casca branca (Coturnix coturnix japonica) da linhagem NISSEI e amostras dos vírus que acometem aves (vírus da doença de Newcastle, vírus da varíola aviária e vírus da bronquite infecciosa das galinhas) e também em outras espécies como vírus da influenza equina. Nos ovos inoculados com o vírus de Newcastle foi coletado o liquido alantoíde para a realização do teste de HA, que apresentou melhor resultado no tempo de 72 horas com o volume de 100μl. Na inoculação do vírus da varíola aviária foram coletadas as membranas corioalantoídes para analisar as les es po e an lise histopatol gica, sendo que todos os volumes utilizados (20, 40, 80 e 100μl) apresentaram lesões características desta enfermidade. Nos vírus da bronquite infecciosa das galinhas, de todos os volumes utilizados, somente o de 40μl produziu lesões no embrião, como nanismo e enrolamento. A replicação do vírus influenza equina, assim como aconteceu com o VDN, foi dependente da concentração e o tempo de incubação, sendo o melhor tempo o intervalo de 48 horas, utilizando o volume de 40μl. Os ovos embrionados de codornas de casca branca também foram utilizados para testar a viabilidade de uso em cultivo primário de fibroblastos, sendo que os mesmos permaneceram viáveis após quatro passagens in vitro. Este modelo biológico foi eficiente para replicação do vírus da doença de Newcastle, vírus da varíola aviária, vírus da bronquite infecciosa das galinhas e vírus da influenza equina. Estes embriões se mostraram aptos também para serem utilizados em cultivo primário de fibroblastos. / Quail embryonated eggs may be used for inoculation of several viruses by different ways, like the well-known techniques used in embryonated chicken (Gallus domesticus) eggs with some light adjustments. Some advantages may be assigned to this process like: lower production costs, reduction in incubation time, no need for large spaces and, maybe the most important one, for being a different species of Gallus domesticus and so, not carrying antigens and antibodies of interest for modern commercial poultry, it does not interfere in the diagnose or in the viral replication. To assess the viral replication potential, we used a total of 351 embryonated quail eggs of white eggshell type (Coturnix coturnix japonica) NISSEI lineage and samples of virus that affect birds (Newcastle disease virus, avipoxvirus and infectious bronchitis chickens and also, some other species like the equine influenza virus.From the eggs inoculated with Newcastle virus it was collected the allantois fluid to perform HA test which presented the better result for 72 hours period and a volume of 100μl. From the inoculation with Fowl pox we collected the chorioallantoic membrane o analyze both pox lesions and for histopathological analysis, all considered volumes (20, 40, 80 e 100μl) presented the disease characteristic lesions. For the Chicken Infectious Bronchitis Virus, from all considered volumes used only the 40μl volume produced embryo lesion like dwarfism and winding. The Equine Influenza Virus replication similar to what was observed with NDV was concentration and incubation time dependent, being the best result achieved for a 48 hours interval using a 40μl volume. White Shell quail embryonated eggs were also used to test its viability for primary cultures of fibroblasts and it was verified that they remain viable after four passages in vitro. This biological model demonstrated efficient for virus replication of Newcastle Disease, Fowl Pox, infectious bronchitis chickens and for equine influenza virus. These embryos also proved suitable for use in primary fibroblasts culture.
118

Dissecting Phenotypic Variation in Pigmentation using Forward and Reverse Genetics

Hellström, Anders R January 2010 (has links)
Coat color and patterning phenotypes have been extensively studied as a model for advancing our understanding of the relationship between genetic and phenotypic variation. In this thesis, genes of relevance for pigment cell biology were investigated. The dissertation is divided in two parts. Forward genetics was used in the first part (Paper I and II) to identify the genes controlling the Silver and Sex-linked barring loci in chicken. In the second part, reverse genetics was employed to create a mouse line in which the PMEL17 protein is inactivated (Paper III). In Paper I, we report five mutations in SLC45A2 causing plumage color variants in both chicken and Japanese quail. Normal function of the SLC45A2 gene has previously been shown to be essential for the synthesis of both red/yellow pigment (pheomelanin) and brown/black pigment (eumelanin) in numerous species, including humans. The major discovery in this paper is the specific inhibition of pheomelanin in Silver chickens, whilst null mutations at this locus cause an almost complete absence of both pheomelanin and eumelanin. In Paper II, we report that Sex-linked barring in chickens is controlled by the CDKN2A/B tumor suppressor locus. The locus encodes two proteins, INK4B and ARF. The genetic analysis indicates that missense mutations in ARF or mutations in the promoter region of the ARF transcript are causing Sex-linked barring. In previous studies, mutations inactivating the CDKN2A/B tumor suppressor locus, have been shown to be responsible for familiar forms of human melanoma. Here we propose that these mutations in chicken CDKN2A/B cause the premature cell death of melanocytes as opposed to the cell proliferation and tumor growth associated with loss-of-function alleles in humans. In Paper III, we created a mouse line in which the PMEL17 protein is inactivated. Missense mutations in the gene encoding PMEL17 have previously been shown to be associated with reduced levels of eumelanin in epidermal tissues in several vertebrate species. The knockout mice are viable, fertile, and display no obvious developmental defects. The eumelanosomes within the melanocytes of these mice are spherical in contrast to the cigar-like shaped eumelanosomes present in wild-type animals. PMEL17 protein inactivation has only a subtle diluting effect on the coat color phenotype in four different genetic backgrounds. This suggests that other previously described alleles in vertebrates with more striking effects on pigmentation are dominant-negative mutations.
119

Qualidade interna e externa de ovos de codornas japonesas armazenados em diferentes temperaturas e períodos de estocagem / Internal e external quality eggs Japanese quail eggs stored in different temperatures and periods of storage

Marinho, Andreza Lourenço 21 February 2012 (has links)
With the aim of evaluating the internal and external of eggs of quality quail stored under refrigeration and at room temperature, we used 440 eggs Japanese quail collected after laying. The eggs were distributed in a completely randomized design in factorial 2x11 (2 storage temperature x 11 storage periods) with 20 repetitions. Analyses were performed on eggs at 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 and 30 days of storage. The variables analyzed were weight loss (%), specific gravity (g / ml), yolk index and albumen percentages (%) of yolk, albumen and shell, shell thickness (mm), yolk color, pH albumen and yolk and Haugh Unit. Statistical analysis was performed using the System Analysis Statistical and Genetic (SAEG) and means compared by Newman Keuls test at 5% probability. Observed effect was (P<0,05) linear weight loss of eggs (%), specific gravity (g / ml), yolk index, albumen index, albumen percentage, yolk percentage, pH and yolk Haugh unit, in both storage temperatures. However, the pH of the albumen had an effect (P<0,05) quadratic for eggs stored at both storage temperatures. To eggshell percentage, shell thickness and yolk color not found a significant effect (P>0,05) among treatments. We conclude that Japanese quail eggs can be stored for up to 18 days at room temperature and 30 days under refrigeration. / Fundação de Amparo a Pesquisa do Estado de Alagoas / Com o objetivo de avaliar a qualidade interna e externa de ovos de codornas armazenados sob refrigeração e à temperatura ambiente, utilizou-se 440 ovos de codornas japonesas coletados após a postura. Os ovos foram distribuídos em um delineamento inteiramente casualizado em esquema fatorial 2x11 (2 temperaturas de armazenamento x 11 períodos de armazenamento) com 20 repetições. As análises foram efetuadas nos ovos com 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 e 30 dias de armazenamento. As variáveis analisadas foram: perda de peso (%), gravidade específica (g/ml), índice de gema e de albúmen, porcentagens (%) de gema, albúmen e casca, espessura de casca (mm), coloração da gema, pH do albúmen e da gema e a Unidade Haugh. As análises estatísticas foram realizadas, utilizando o Sistema para Análises Estatísticas e Genética (SAEG) e as médias comparadas pelo teste Newman Keuls a 5% de probabilidade. Observou-se efeito (P<0,05) linear para perda de peso dos ovos (%), gravidade especifica (g/ml), índice de gema, índice de albúmen, porcentagem de albúmen, pH da gema e unidade Haugh, em ambas as temperaturas de estocagem e porcentagem de gema para os ovos armazenados sob refrigeração. Contudo, o pH do albúmen apresentou efeito (P<0,05) quadrático para os ovos armazenados em ambas as temperaturas de estocagem e a porcentagem de gema para os ovos armazenados em temperatura ambiente. Para porcentagem de casca, espessura da casca e coloração da gema não se constatou efeito significativo (P>0,05) entre os tratamentos. Concluiu-se que ovos de codornas japonesas podem ser armazenados por até 18 dias em temperatura ambiente e 30 dias sob refrigeração.
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Rastreabilidade da farinha de vísceras de aves em codornas submetidas a longo período de criação utilizando a técnica dos isótopos estáveis 'delta' 'intpot. 13 c' e 'delta' 'intpot. 15 N' /

Sernagiotto, Erica Regina, 1983- January 2009 (has links)
Orientador: Antonio Celso Pezzato / Banca: Carlosw Ducatti / Banca: Valquíria Cação da Cruz / Resumo: O presente trabalho teve por objetivo avaliar a capacidade da técnica dos isótopos estáveis em rastrear a farinha de vísceras de aves (FVA), na alimentação de codornas de corte criadas por longo período, após a substituição da dieta com 8% de FVA por dieta vegetal. Foram utilizadas 320 codornas, distribuídas aleatoriamente em oito tratamentos: dieta vegetal (T1) e sete tratamentos com inclusão de 8% de FVA na dieta, um mantendo a dieta até o final do período experimental (T2), e nos demais a dieta foi substituída aos 42; 56; 70; 84; 98; 112 dias; respectivamente, por dieta vegetal. Para coleta das amostras de músculo peitoral foram sacrificadas ao acaso, quatro aves (n = 4) por tratamento, a cada 14 dias, sendo que no T1 e T2 tiveram início aos 42 dias e nos demais a partir da troca das dietas. Os resultados isotópicos obtidos foram submetidos à análise multivariada de variância (MANOVA) com auxílio do procedimento GLM do programa estatístico SAS. Os tratamentos diferiram do vegetal quando as aves foram sacrificadas duas semanas após a troca da dieta; após esse período os tratamentos experimentais tiveram comportamento semelhante ao vegetal, exceto o T3, que se mostrou semelhante ao T1 no abate 14 dias após a troca da dieta; e do T2 que em todos os períodos de comparação diferiu do T1. Conclui-se que a aplicação da técnica dos isótopos estáveis de carbono e nitrogênio na rastreabilidade da FVA, na alimentação de codornas de corte criadas por longo período é possível nas aves abatidas 14 dias após a troca de dieta, com exceção das aves sacrificadas aos 56 dias de idade. / Abstract: The present work aimed to evaluate the capability of the stable isotope technique to trace poultry visceral meal (PVM) in the diet of meat quails raised for a long period after substitution of an 8% PVM diet for a vegetable diet. Three hundred and twenty poultries (320) were randomly distributed into eight treatments: vegetable diet (T1) and seven treatments containing 8% PVM in the diet: in one treatment, the same diet was kept until the end of the experimental period (T2), and in the remaining treatments, the diet was substituted at 42, 56, 70, 84, 98, and 112 days, respectively, for a vegetable diet. To collect chest muscle samples, four poultries (n = 4) per treatment were randomly sacrificed at every 14 days, starting at 42 days in T1 and T2 and from diet substitution in the remaining treatments. The obtained isotopic results were subjected to multivariate analysis of variance (MANOVA) using the GLM procedure of SAS statistical software. Treatments differed from the vegetable diet when poultries were sacrificed at two weeks following the diet substitution; after such period, the behavior of experimental treatments was similar to that of the vegetable diet, except for T3, which was similar to T1 at slaughtering at 14 days after the diet substitution, and T2 which, in all comparison periods, differed from T1. In conclusion, the technique of stable isotopes of carbon and nitrogen can be used to trace PVM in the diet of meat quails slaughtered at 14 days after diet substitution, except for poultries sacrificed at 56 days. / Mestre

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