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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.
21

Biomassa de rubrivivax gelatinosus como suplemento de rações para galinhas poedeiras

Polonio, Lorrayne Bernegossi [UNESP] 12 April 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04-12Bitstream added on 2014-06-13T18:55:53Z : No. of bitstreams: 1 polonio_lb_me_araca.pdf: 658865 bytes, checksum: 7582c5292a72975d73a80166a2abfd40 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os efeitos da adição de biomassa de Rubrivivax gelatinosus em dietas de galinhas poedeiras foram investigados. Sorgo e milho foram utilizados para formulação de rações basais que receberam níveis crescentes de biomassa. A biomassa bacteriana aumentou a tonalidade de vermelho e diminuiu a luminosidade das gemas quando adicionada a ambas as rações basais. Na ração à base de milho, 1.500ppm de biomassa foram suficientes para alcançar a preferência do consumidor, enquanto que, com ração à base de sorgo, 7.500ppm foram necessários para atingir o mesmo objetivo. Galinhas alimentadas com ração à base de milho tiveram consumo de ração superior e melhor conversão alimentar que aquelas alimentadas com ração à base de sorgo, mas os níveis de inclusão da biomassa em ambas as rações basais não influenciaram estes parâmetros. Durante o período experimental não ocorreu mortalidade nem mudança no peso das galinhas. As galinhas alimentadas com ração à base de milho mostraram taxas superiores de produção de ovos, peso e massa de ovos que aquelas alimentadas com ração à base de sorgo. Estes parâmetros não foram influenciados pela inclusão de níveis de biomassa em ambos os tipos de ração. Níveis normais para enzimas séricas e ausência de lesões degenerativas e inflamatórias nos fígados e nos rins das galinhas permitem a indicação da biomassa para suplementação de rações. / The effects of the dietary inclusion of Rvi. gelatinosus biomass in layers rations were investigated. Sorghum and corn were used for the formulation of basal rations that received increasing levels of biomass. The bacterial biomass increased red hues and decreased lightness of yolks when added to both basal rations. Biomass at 1,500ppm in the corn-based ration was enough to reach consumers` preference, while with the sorghum-based ration, 7,500ppm were necessary to reach the same. Hens fed corn-based rations had superior feed consumption and better feed conversion than those fed sorghum-based rations but the inclusion levels of the biomass on both basal rations did not influence these parameters. No mortality and no change on layers weight occurred during the experimental period. Hens fed corn-based rations showed superior egg production, egg weight and egg mass rates than those fed sorghum-based rations. These parameters were not influenced by the inclusion levels of the biomass on both kinds of rations. Normal levels for seric enzymes and the absence of degenerative and inflammatory lesions in livers and kidneys of hens allow the indication of the biomass for ration supplementation.
22

Efeito da substituição da gema de ovo pela lecitina de soja na criopreservação de sêmen equino /

Felício, Gabriel Barcellos. January 2008 (has links)
Orientador: Frederico Ozanam Papa / Banca: Marco Antônio Alvarenga / Banca: Rubens Paes de Arruda / Resumo: O objetivo do presente trabalho foi verificar a eficiência na congelabilidade e fertilidade da substituição da gema de ovo pela lecitina de soja no diluidor comercial Botu-Crio® (BC). Foram realizados dois experimentos laboratoriais e os respectivos testes de fertilidade. No experimento I comparou-se o diluente Botu-Crio® com o diluidor o Botu-Crio em que a gema de ovo foi substituída pela lecitina de soja numa concentração de 45g/L (BCLS45). Utilizou-se um ejaculado de 15 garanhões da raça Brasileiro de Hipismo (BH). Para o teste de fertilidade do Experimento I foi utilizado um garanhão da raça BH. Foram inseminados 12 éguas com o BC e 17 com o BCLS45. No experimento II comparou-se o diluente BC com o Botu-Crio sem gema de ovo (BCLS) acrescido de diferentes concentrações de lecitina de soja: 10,0; 12,5; 15,0; 17,5 e 20,0g/L (BCLS10; BCLS 12,5; BCLS15; BCLS17,5 e BCLS 20). Para tal, foram utilizados 1 ejaculado de 10 garanhões dde diferentes raças. Para o teste de fertilidade do experimento II utilizou-se um garanhão da raça Trakener e foram realizadas inseminações comparativas entre BC e BCLF20, sendo utilizadas 12 éguas com BC vs 10 éguas com BCLS20. Também comparou-se os diluente BC com o BCLS10, no qual foi utilizado um garanhão da raça Westfalen e foram inseminadas 8 éguas com BC vs 12 éguas com BCLS10. No Experimento I, os resultados de motilidade total, (61,4±16,2x61,4±15,9); motilidade progressiva, (27,0±9,8x26,7±10,6); íntegridade da membrana plasmática (IMP) (53,4±11,5x57,4±7,0); respectivamente para os diluidores Botu-Crio® e BCLS45, não havendo diferença entre os parâmetros espermáticos (p>0,05). No experimento II também não foram observadas diferenças entre os parâmetros avaliados, sendo para motilidade total BC (68,1±15,9) e BCLS10; BCLS12,5; BCLS15; BCLS17,5 e BCLS20 (65,8±13,5; 65,9±17,6; 67,6±11,2; 64,0±15,3 e 60,5±15,3)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of the present study was to verify the freezability and fertility of the BotuCrio without egg yolk extender where the egg yolk was replaced by soy been lecithin. Two experiments were performed on experiment 1 Botu-Crio® (BC) and Botu Crio without egg yolk containing 45g/L soy been lecithin (BCLS45) were compared. One ejaculated from 15 stallions from Braziliam Jump Horse Bred were used. On experiment 2, different concentrations of de soy bean lecithin: 10,0; 12,5; 15,0; 17,5 e 20,0g/L (BCLS10, BCLS12,5, BCLS17,5 e BCLS20) were compared. On the first fertility trial 12 mares were inseminated. With BC and 17 mares with Botu-Crio without egg yolk (BCLS45) using semen from only one stallion. On the second fertility trial 12 mares were inseminated with BC and another 10 mares with BCLS20. In another fertility trial 12 mares were inseminated with Botu-Crio vs and 8 mares with BCLS10 using frozen semen from a Westfalen stallion. No differences were observed on total motility (61.4 x 61.4); progressive motility, (27.0x26.7); plasmatic menbrane integrity (IMP) (53.4x57.4); between Botu-Crio® and Botu-Crio without egg yolk, (p>0,05). Also no differences were observed when different concentrations of soy been lecithin were used. The results were : For total motility BC (68,1±15,9) BCLS10, BCLS12,5, BCLS17,5 , BCLS20 (65,8±13,5; 65,9±17,6; 67,6±11,2; 64,0±15,3 ,60,5±15,3), for progressive motility: BC (28,8±9,2) and BCLS10, BCLS12,5, BCLS17,5 e BCLS20(29,8±9,8; 29,6±9,7; 31,4±8,2; 30,2±10,5 and 26,6±11,5) and IMP BC (50,7±10,3) and BCLS10, BCLS12,5, BCLS17,5 e BCLS20 (47,5±8,5; 46,6±12,2; 49,9±8,8; 46,1±10,3 and 43,6±10,9). The results of the fertility trials were: BC vs BCLS45 , 66,0 e 17% respectively (p<0,01); BC vs BCLS20 66,0 e 40,0% e BC vs BCLS10 75,0 e 41,0 respectively. In spite of similar laboratorial finds the fertility was different between... (Complete abstract click electronic access below) / Mestre
23

Criopreservação do sêmen equino: comparação da gema de ovo de ema (Rhea americana ) com a gema de ovo de galinha

Linden, Liana de Salles van der January 2012 (has links)
O objetivo deste trabalho foi comparar a utilização de diluentes comerciais à base de gema de ovo de galinha com os mesmos diluentes, nos quais se substituiu a gema de galinha pela de ovo de ema (Rhea americana). Foram utilizados Seis garanhões da raça Crioula, comprovadamente férteis e no período fora da estação de monta e utilizados seis ejaculados de cada garanhão. O sêmen foi avaliado macroscopicamente quanto ao volume, aspecto e coloração, a seguir avaliou-se a motilidade progressiva e total. Posteriormente o sêmen foi dividido em quatro alíquotas e diluído na proporção 1:1 com o diluente, Equimix (Nutricell Nutrientes Celulares) para centrifugação. Para adição do diluente de congelamento foram utilizados: diluente A (FR-5, Nutricell Nutrientes Celulares) e diluente B (Botu-crio, Biotech Botucatu S.A.) adicionados de 20 % de gema de ovo de ema, ou de 20 % de gema de ovo de galinha. As amostras foram envasadas, identificadas e submetidas a congelamento conforme o protocolo. As palhetas foram descongeladas, após um período mínimo de 7 dias e examinadas para os seguintes quesitos: motilidade total e progressiva, e integridade física e funcional da membrana plasmática do espermatozoide. Os diluentes comerciais com ou sem adição de gema de ovo de ema não apresentaram diferenças em relação à motilidade total e progressiva, porém observou-se diferença nos parâmetros quando comparados os diluentes comerciais. Houve diferença na funcionalidade da membrana apenas quando comparado diluente A e B com gema de ovo de ema. No quesito integridade de membrana não foi observado diferença estatística. Estes resultados demonstram que a gema de ovo de ema (Rhea americana) pode ser uma alternativa para produção de diluentes para congelamento de sêmen de equinos. / The aim of this study was to compare the use of two commercial extenders using chicken egg yolk with the same extenders, to which ema (Rhea americana) egg yolk was added. Six Criollo breed stallions were used during the off-breeding season period. Six collections per stallion were used. The ejaculate aspect, total and progressive motility were evaluated with a microscope; concentration was determined with a Neubauer counting chamber. After evaluation, semen samples were divided in two aliquots and diluted 1:1 in each of the centrifugation extender Equimix (Nutricell Nutrientes Celulares). For freeze that semen we used two commercial extenders: A (extender with glycerol) or B (extender with methylformamide) and was added 20% rhea egg yolk or 20% chicken egg yolk . Semen samples were examined at least 1 week after freezing, for total and progressive motility, physical and functional membrane integrity (HOST test and CFDA-PI fluorescence) (Lagares et al. 1998; Harrison & Vickers, 1990). The extenders of a given brand with or without rhea egg yolk had no significant difference according to total and progressive motility, although there was difference (p = 0,05) between extenders when different brands were compared, no matter if they were added Rhea egg yolk or not. Membrane functionality showed difference only when compared Extender A and B with Rhea egg yolk. Membrane integrity had no significant difference between all the treatments. These results show that Rhea egg yolk might be an alternative to making an equine semen extender.
24

Criopreservação do sêmen equino: comparação da gema de ovo de ema (Rhea americana ) com a gema de ovo de galinha

Linden, Liana de Salles van der January 2012 (has links)
O objetivo deste trabalho foi comparar a utilização de diluentes comerciais à base de gema de ovo de galinha com os mesmos diluentes, nos quais se substituiu a gema de galinha pela de ovo de ema (Rhea americana). Foram utilizados Seis garanhões da raça Crioula, comprovadamente férteis e no período fora da estação de monta e utilizados seis ejaculados de cada garanhão. O sêmen foi avaliado macroscopicamente quanto ao volume, aspecto e coloração, a seguir avaliou-se a motilidade progressiva e total. Posteriormente o sêmen foi dividido em quatro alíquotas e diluído na proporção 1:1 com o diluente, Equimix (Nutricell Nutrientes Celulares) para centrifugação. Para adição do diluente de congelamento foram utilizados: diluente A (FR-5, Nutricell Nutrientes Celulares) e diluente B (Botu-crio, Biotech Botucatu S.A.) adicionados de 20 % de gema de ovo de ema, ou de 20 % de gema de ovo de galinha. As amostras foram envasadas, identificadas e submetidas a congelamento conforme o protocolo. As palhetas foram descongeladas, após um período mínimo de 7 dias e examinadas para os seguintes quesitos: motilidade total e progressiva, e integridade física e funcional da membrana plasmática do espermatozoide. Os diluentes comerciais com ou sem adição de gema de ovo de ema não apresentaram diferenças em relação à motilidade total e progressiva, porém observou-se diferença nos parâmetros quando comparados os diluentes comerciais. Houve diferença na funcionalidade da membrana apenas quando comparado diluente A e B com gema de ovo de ema. No quesito integridade de membrana não foi observado diferença estatística. Estes resultados demonstram que a gema de ovo de ema (Rhea americana) pode ser uma alternativa para produção de diluentes para congelamento de sêmen de equinos. / The aim of this study was to compare the use of two commercial extenders using chicken egg yolk with the same extenders, to which ema (Rhea americana) egg yolk was added. Six Criollo breed stallions were used during the off-breeding season period. Six collections per stallion were used. The ejaculate aspect, total and progressive motility were evaluated with a microscope; concentration was determined with a Neubauer counting chamber. After evaluation, semen samples were divided in two aliquots and diluted 1:1 in each of the centrifugation extender Equimix (Nutricell Nutrientes Celulares). For freeze that semen we used two commercial extenders: A (extender with glycerol) or B (extender with methylformamide) and was added 20% rhea egg yolk or 20% chicken egg yolk . Semen samples were examined at least 1 week after freezing, for total and progressive motility, physical and functional membrane integrity (HOST test and CFDA-PI fluorescence) (Lagares et al. 1998; Harrison & Vickers, 1990). The extenders of a given brand with or without rhea egg yolk had no significant difference according to total and progressive motility, although there was difference (p = 0,05) between extenders when different brands were compared, no matter if they were added Rhea egg yolk or not. Membrane functionality showed difference only when compared Extender A and B with Rhea egg yolk. Membrane integrity had no significant difference between all the treatments. These results show that Rhea egg yolk might be an alternative to making an equine semen extender.
25

Evaluation of Nguni bull semen-extended in tris egg yolk extender, soybean milk and coconut water based extenders and stored at different temperatures

Mayombo, Pie Veillard Kalonji 18 September 2017 (has links)
MSCAGR (Animal Science) / Department of Animal Science / In order to realize many of the potential advantages of AI, storage of semen is necessary. Semen storage is only possible using a system that decreases and/or halts the metabolic processes of the spermatozoa, allowing no significant loss of fertility. Numerous factors affect the success of spermatozoa storage. This study was designed to compare the effects of egg yolk, soybean milk and coconut water in Tris extender using different storage methods for Nguni bull spermatozoa storage. Bull semen was collected from two adult Nguni bulls approximately four years old and kept under similar managerial conditions. Using electro-ejaculator, semen was collected from each bull into a graduated semen collection tube. Macroscopically evaluation of the sample was performed immediately after collection. Only the semen free from contamination was processed. The kinetic properties namely: total spermatozoa motility, and progressive spermatozoa motility were analysed using CASA. Semen sample was stained and spermatozoa morphology and vitality also analysed using CASA. The extended semen was then split into three groups. The first group was stored at room temperature (25 °C). The second group was cooled to 4 °C and stored in the refrigerator. The third group was also cooled to 4 °C for 2 h in the refrigerator, then held in LN2 vapour 5 cm above the surface of LN2 at ~ -80 °C for 10 min and then plunged into LN2 for storage at -196 °C. Different colours of straws and plugging powder were used for identifying each extender. After 3 days of storage at room temperature, in the refrigerator and in LN2, the extended semen was split into three portions and assayed for kinetic properties using the first portion. The second portion was assayed for spermatozoa morphology and the third portion for spermatozoa vitality. The results from the fresh semen extended with all three extenders (TEYE, SBME and COWE), and analysed immediately after dilution at room temperature (25 ºC), showed no significant difference (P > 0.05) in the mean values of the kinetic and morphologic properties and viability, on spermatozoa TM, PM, AR, AT, CT; BT and LS. After three days of storage, there was no significant difference (P > 0.05) in the kinetic morphologic properties and viability of semen stored at room and refrigeration temperature regardless of the extender in use. There were, however, significant differences (P < 0.05) in the TM, PM, AR and DL of the frozen semen samples. For the short storage period of semen used for AI, from this study, it is recommended that semen should be kept at room or refrigeration temperature regardless of the three extenders used. However, for long storage of frozen semen TEYE is recommended. The egg yolk-based extender provided greater preservation of motility and bull spermatozoa integrity during the freezing process than did SBME and COWE.
26

The Recovery of Protein from Egg Yolk Protein Extraction Granule Byproduct

Kaufman, Irene Jennifer 01 June 2017 (has links)
In addition to proving an excellent source of nutrients, eggs are used in the food, cosmetic, and biotechnology industries for their rheological and bioactive properties. Much of the potential for the added value is in individual components of the egg, rather than the whole egg. At low speed centrifugation, yolk separates into two distinct fractions—granules and plasma. It is becoming increasingly popular in the industry to remove the plasma fraction of the egg yolk to use for its livetins, particularly immunoglobulin Y, leaving behind a granule by-product (“yellow cake”). Previous research has shown potential added-value from the granule fraction, especially from its phosvitin and phospholipids. Granules are protein aggregates with complexes of phosvitin and high density lipoproteins linked by phosphocalcic bridges. In their native form, the proteins are mostly insoluble, however previous studies have shown the links can be broken by alterations in pH, ionic strength, and mechanical treatments. This thesis project seeks to find potential uses for the egg yolk by product after the removal of the livetin fraction by means of further fractionation with mechanical treatment (filtration). Two variables were tested to extract more proteins from the yellow cake. Salt was added to 10% solids solution of yellow cake in water before filtration at four different NaCl levels: 0%, .05%, 1%, and 2.5%. Additionally pH was tested at four different levels: 4.6, 4.8, 5.0, 5.2. The samples were also tested for antibacterial properties against Escherichia v coli with a minimum inhibitory concentration assay (MIC). Analysis with BCA showed salt concentration had a significant effect on the yield of protein. The highest concentration of salt tested, 2.5%, had the highest protein yield. Additionally, SDS PAGE showed 2.5% salt had the most unique protein bands. This could be to the disruption of the phosphocalcic links between the phosvitin and HDL by NaCl, allowing the protein to solubilize. pH did not have a significant effect on the yield or types of proteins in the range tested in this experiment. There is no conclusive evidence of antibacterial properties against E. coli from the protein extract. The MIC assay had growth show up in all wells with the protein extract, however there was a visible decrease in turbidity with higher concentration of the protein extract. This could mean that the protein extract does have some antibacterial properties, but needs testing at higher concentrations or with isolated proteins/peptides. The SDS-PAGE revealed bands showing phosvitin present, which has known antibacterial properties. Overall, improvements to the methods for further protein extraction from egg yolk by-products will help lead the industry to finding novel uses and product applications.
27

Comparing the mannitol-egg yolk-polymyxin agar plating method to the three tube most probable number method for enumeration of bacillus cereus spores in raw and high-temperature-short-time pasteurized milk

Harper, Nigel Murray January 1900 (has links)
Master of Science / Food Science Institute- Animal Sciences and Industry / Kelly J. K. Getty / The Food and Drug Administration’s Bacteriological Analytical Manual recommends two enumeration methods for Bacillus spp.: 1) standard plating method using mannitol-egg yolk-polymyxin (MYP) agar and 2) most probable number (MPN) method with tryptic soy broth supplemented with 0.1% polymyxin sulfate. Preliminary research evaluated three inoculum preparation methods using EZ-Spore™ B. cereus pellets. Two methods involved EZ-Spore™ B. cereus pellets that were dissolved in deionized (DI) water, grown in brain heart infusion broth with manganese sulfate, and then heated to produce spores. The third inoculum preparation method of dissolving EZ-Spore™ pellets only in DI water was the most efficient due to 100% spores being present in the inoculum. Preliminary research also determined that MPN method recovered greater (p<0.05) B. cereus populations than MYP method in inoculated ultra-high temperature pasteurized skim and 2% milk. The objective of the main study was to compare the MYP and MPN method for detection and enumeration of B. cereus in raw and high-temperature-short-time pasteurized skim, 2%, and whole milk at 4 °C for 96 h. Milk samples were inoculated with B. cereus EZ-Spores™ dissolved in DI water and sampled at 0, 48, and 96 h after inoculation. No differences (p>0.05) were observed among sampling times so data was pooled for overall mean values for each treatment. The overall B. cereus population mean of pooled sampling times for MPN method (2.59 log CFU/mL) was greater (p<0.05) than MYP plating method (1.89 log CFU/mL). B. cereus populations ranged from 3.40 log CFU/mL to 2.40 log CFU/mL for inoculated milk treatments for MYP and MPN methods, which is well below the necessary level for toxin production. Even though MPN method enumerated more B. cereus, the MYP method should be used by industry for enumeration of B. cereus due to its ease of use and rapid turnover time (2 d compared to 5 d with MPN). However, MPN method should be used for validation research due to its greater populations recovered. EZ-Spore™ B. cereus pellets were found to be an acceptable spore inoculum for validation research because the inoculum consists of 100% spores and does not contain vegetative cells.
28

Omega-3 fatty acid enrichment of chicken eggs: Regulation of long chain polyunsaturated fatty acid metabolism in laying hens

Neijat, Mohamed January 2016 (has links)
Eggs enriched with omega-3 polyunsaturated fatty acids (PUFA), particularly the longer chain PUFA (LCPUFA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) can boost human consumption of these fatty acids implicated in human health. Alpha-linolenic acid (ALA) from plant seeds/oils, primarily serve as the source of omega-3 PUFA for hens, however, the scarcity of ALA-rich plants and the limited conversion of ALA to LCPUFA are challenges for egg enrichment. Two major experiments were conducted to determine potential factors regulating egg enrichment of omega-3 LCPUFA based on detailed assessment of PUFA profiles in different lipid pools of hen tissues. In experiment 1, supplementation of graded levels of hempseed products, provided ~ 0.1 to 1.3% of ALA in the diets. Experiment 2, investigated dietary supplementation of flaxseed oil (ALA-rich) and algal DHA (preformed LCPUFA), each providing similar graded levels of total omega-3 PUFA. Both ALA-containing models demonstrated a plateau in DHA enrichment of eggs at higher ALA intakes. ALA-containing diets led to high concentrations of ALA in the triacylglycerol (TAG) fraction of eggs and plasma, and the adipose tissue of flaxseed oil-fed hens. In total phospholipid (PL), particularly the phosphatidylethanolamine (PE), the levels of EPA and ALA in the yolk were linearly associated with those in the liver. In all tissues, DHA dominated the PE pool, exhibiting a plateau with a strong inverse correlation to the ratio of ALA to EPA in the liver, suggesting limited ALA availability for egg DHA enrichment. The use of algal DHA should therefore permit further accumulation of DHA in the total PL and TAG fractions of yolk. However, enrichment via preformed DHA (at 3.36% algal product) was also limited by hepatic PL resulting in more DHA and EPA being shunted to the adipose TAG, concurrent with elevated hepatic acyl-CoA synthetase (ACSL1) expression. As a function of total omega-3 PUFA intakes (regardless of source), similar levels of stearidonic acid (SDA) and particularly EPA accumulated in liver PE. Therefore, hepatic PL regulation, possibly aimed at maintaining EPA level, may potentially be limiting the amount of ALA accumulation in the same pool, hence limiting the endogenous synthesis of DHA and subsequent enrichment in eggs. / February 2017
29

Novas percepções sobre o uso de lecitina de soja na criopreservação e fertilidade de espermatozoide bovino / New insights on the use of soybean lecithin on bovine sperm cryopreservation and fertility

Rodrigues, Mariana de Paula 21 February 2014 (has links)
A grande demanda por proteína animal e a importância que a criação bovina exerce sobre a economia nacional, vêm exigindo eficientes sistemas de produção. A preservação e disseminação da genética do rebanho bovino dependem de biotecnologias como a criopreservação espermática, inseminação artificial e fertilização in vitro. No entanto, atualmente muito tem sido discutido sobre o uso da gema de ovo nos diluidores seminais. Pois apresentam variabilidade em sua composição e risco de contaminação microbiológica. Em contrapartida, apesar dos diluidores sintetizados com lecitina de soja não fornecerem esses riscos, seus resultados não são muito satisfatórios na criopreservação espermática bovina. Com base na hipótese de que a suplementação do diluidor seminal à base de lecitina de soja com antioxidantes, preserve as características das células espermáticas de maneira tão eficiente quanto à gema de ovo, o objetivo do presente experimento foi comparar o efeito do diluidor à base de gema de ovo com o diluidor à base de lecitina de soja (com e sem antioxidantes), sobre a manutenção da funcionalidade e fertilidade de amostras espermáticas bovinas criopreservadas. Para tal, foram utilizadas amostras seminais de 20 touros Brangus, cujas colheitas foram realizadas pelo método de eletroejaculação e as amostras foram diluídas em 4 grupos de diluidores: LElecitina de soja (sem a adição de antioxidantes); LAlecitina de soja suplementada com ácido ascórbico (AA, 4,5mM); LS lecitina de soja suplementada com superóxido dismutase (SOD, 60UI/mL) e GOgema de ovo (sem adição de antioxidantes). O sêmen foi então, criopreservado de maneira automatizada. As amostras foram descongeladas e analisadas quanto aos testes laboratoriais de motilidade computadorizada do espermatozóide (CASA); integridade de membrana plasmática (eosina/nigrosina); integridade de membrana acrossomal (fast Green/ rosa bengala); atividade citoquímica mitocondrial (DAB); susceptibilidade do DNA à desnaturação (SCSA); índice de estresse oxidativo induzido (TBARS). Além disso, foram realizados testes para verificar o potencial de fertilidade das amostras espermáticas criopreservadas. A fertilidade in vivo foi realizada pela técnica de inseminação artificial em tempo fixo (IATF), utilizando 450 fêmeas bovinas, seguido de exame ultrassonográfico para avaliação de prenhez. Teste de fertilidade in vitro, foi realizado pela técnica de produção in vitro de embriões (PIV) com o uso de ovários de frigoríficos, a classificação do desenvolvimento embrionário e a avaliação da motilidade espermática foram promovidas no decorrer do processo. Os resultados demonstraram que o diluidor LE apresentou efeito na proteção espermática de maneira semelhante ao diluidor GO. No entanto a suplementação desse primeiro com antioxidantes é uma alternativa para melhorar ainda mais esse processo, já que a taxa de prenhez obtida nos grupos LA e LS é satisfatória em um programa de IATF. Ainda o grupo LS foi o que apresentou melhores resultados no processo de PIV. Concluindo que o diluidor à base de lecitina de soja suplementado com o antioxidante superóxido dismutase seria uma opção para a substituição definitiva dos diluidores sintetizados com gema de ovo. / Due to the great demand for animal protein and the importance that bovine breeding exert on national economy, efficient production systems have been required. Cattle genetics preservation and dissemination depend on reproductive biotechnologies such as sperm cryopreservation, artificial insemination and in vitro fertilization. However, the use of egg yolk-based extender is under discussion nowadays, once there is great variability in its composition and risks of bacteriological contamination. On the other hand, despite soybean lecithin-based extenders do not present these risks, satisfactory results, after bovine sperm cryopreservation, have not been reached yet. Based on the hypothesis that soybean lecithinbased extender supplemented with antioxidants, preserve the sperm cell characteristics so efficient as egg yolk does, the aim of the present experiment was to compare the effects of egg yolk-based extender and soybean lecithin-based extender (with and without antioxidants), on functionality and fertility maintenance of bovine cryopreserved sperm samples. For this, seminal samples from 20 Brangus bulls were used, collects were realized by eletroejaculation method and samples were diluted in 4 extenders group: LE-soybean lecithin-based extender (without antioxidant supplementation); LA- soybean lecithin supplemented with ascorbic acid (AA, 4,5mM); LS- soybean lecithin supplemented with superoxide dismutase (SOD, 60UI/mL) and GO-egg yolk-based extender (without antioxidant supplementation). Then, semen was cryopreserved by automatic method. Samples were thawed and analyzed by laboratorial tests such as computer assisted semen analysis (CASA); plasma membrane integrity (eosin/nigrosin); acrosome membrane integrity (fast green/ rose bengal); mitochondrial cytochemical activity (DAB); susceptibility of chromatin denaturation (SCSA); induced oxidative stress index (TBARS). Furthermore, tests for fertility potential of cryopreserved semen samples were performed. In vivo fertility was accessed by timed artificial insemination (TAI), 450 bovine females were inseminated, and ultrasonographical exam was realized for pregnancy detection. In vitro fertility test was accessed by embryo in vitro production (IVP), ovaries from slaughterhouses were used, embryo development classification and sperm motility were promoted during the process. Results indicate that sperm protection is similar between LE and GO extenders. However the antioxidant supplementation of soybean lecithin-based extender is a great alternative to improve the process of sperm protection, since pregnancy rate of LA and LS groups was satisfactory for a TAI program. Besides, LS group presented the best results on IVP process. In conclusion, soybean lecithin-based extender supplemented with superoxide dismutase would be a better option for a definite replacement of egg yolk-based extender for sperm bovine cryopreservation.
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Efeito da radiação ionizante e do armazenamento sobre a estabilidade oxidativa do colesterol em ovos crus e processados / Effect of gamma radiation and storage on cholesterol oxidative stability of raw and processed eggs.

Medina, Marliz Klaumann Julca 16 September 2005 (has links)
O ovo tem sido estudado por sua riqueza nutricional, por apresentar interesse industrial, como matéria-prima, e pelo seu elevado conteúdo de colesterol. Ao mesmo tempo, por sua susceptibilidade à contaminação por salmonela, principalmente, é proposta a irradiação ionizante como medida sanitária. O colesterol está sujeito à oxidação, facilitada por vários fatores, entre os quais a radiação ionizante. Os óxidos de colesterol formados, por sua vez, apresentam propriedades biológicas prejudiciais à saúde, relacionadas com a aterogenicidade, citotoxicidade, carcinogenicidade e mutagenicidade, além de outras manifestações. Os objetivos deste trabalho foram avaliar o efeito da radiação ionizante sobre o pH, viscosidade e cor, além da estabilidade oxidativa do colesterol, em ovos crus armazenados e processados. Com o aumento nas doses utilizadas (1, 2 e 3 kGy) houve redução na viscosidade da clara e na cor da gema, além do aumento da oxidação lipídica, medida através das substâncias que reagem ao ácido tiobarbitúrico (TBARS). Parâmetros como umidade, lípides totais e colesterol das gemas não foram influenciados. No caso da umidade e do colesterol, houve alteração significativa pelo armazenamento (30 dias, a 4ºC). O somatório dos óxidos analisados não variou com a irradiação, só individualmente, contudo variaram com o armazenamento. O processamento térmico provocou um aumento significativo das TBARS, mas apesar disso, o somatório dos óxidos não diferiu entre os tratamentos. / The egg have being studied due its nutritional wealth, for show industrial interest as a raw material, e due its higher cholesterol content. At the same time, due its susceptibility to contamination mainly with salmonella, it is being proposed the ionizating radiation as a hygienic measure. Cholesterol is subject to oxidation, that it is facilitated by several factors, among them ionizating radiation. Formed cholesterol oxides, by its turn, show harmful biological properties to human health, as atherogenicity, cytotoxicity, carcinogenicity and mutagenicity, among others. The objectives of this work were evaluate the effect of ionizating radiation over pH, viscosity and color, besides the oxidative stability of cholesterol, in storaged and processed crude eggs. With the increasement of used doses (1, 2 and 3 KGy), there was an reduction in the viscosity of the egg white and in the color yolk egg, besides the increase in lipidic oxidation, measured through tiobarbituric acid-reactive substances (TBARS). Specifications as humidity, total lipids and egg yolk cholesterol were not influenced. In the subject of humidity and of cholesterol, there was an meaningful alteration due storage (30 days in 4ºC). The sum of the analyzed oxides didn\'t variate with the irradiation, only individually, although it did vary with storage. The themical processing caused an meaningful increase of TBARS, but despite this, the oxides sum didn\'t differed between treatments.

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