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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.
51

Padronização de um protocolo para detecção molecular de Leptospira spp. e Brucella spp. em sêmen bovino comercial

Fuverki, Renata Benício Neves [UNESP] 30 June 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-30Bitstream added on 2014-06-13T20:35:29Z : No. of bitstreams: 1 fuverki_rbn_me_jabo.pdf: 380911 bytes, checksum: 1e3cde0d1d852b172186ddec592ea827 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Com a crescente disponibilidade das biotécnicas de reprodução animal, o comércio dos produtos envolvidos com essas práticas também está em expansão, oferecendo a possibilidade de melhoria dos índices zootécnicos às produções de bovinos. Porém deve-se levar em consideração que há riscos sanitários em práticas como a inseminação artificial caso não se realize o controle do material biológico utilizado. Dentre os agentes infecciosos que podem estar presentes no sêmen e passíveis de serem transmitidos por esse estão a leptospirose e a brucelose, enfermidades responsáveis por grandes perdas reprodutivas e econômicas na bovinocultura mundial. Este projeto teve como objetivos detectar molecularmente esses patógenos em amostras de sêmen bovino provenientes de centrais de comercialização brasileiras, utilizando um kit comercial para extração de DNA (“RTP Bacteria DNA Mini Kit” (Invitek®), aperfeiçoá-lo para a extração de DNA bacteriano a partir de sêmen e avaliar sua aplicabilidade à rotina laboratorial. O DNA bacteriano foi extraído e quantificado por eletroforese em gel de agarose. Pretendeu-se também realizar reação em cadeia da polimerase (PCR) utilizando os “primers” B4 e B5 para amplificação do DNA de Brucella spp. e os “primers” Lep 1 e Lep 2 para Leptospira spp. O kit de extração foi otimizado com sucesso, e todas as 96 amostras examinadas foram negativas para qualquer DNA bacteriano. Os resultados podem ser úteis para estabelecer alternativas de controle sanitário em touros doadores de sêmen e permitir o fornecimento de material genético livre de patógenos, aumentando o “status” sanitário da reprodução de bovinos no Brasil / With the increasing disponibility of animal reproduction biotechniques, trading of products involved with these activities is also in expansion offering improving possibilities in zootecnic indexes of bovine herds. However, considerations should be taken about sanitary risks in practices like artificial insemination if any control is applied to this biological material. Among infectious agents that could be present and transmitted by semen are leptospirosis and brucellosis, diseases that are responsible for numerous reproductive and economic losses in world’s cattle culture. The goals of this project were to molecularly detect these pathogens in bovine semen samples from Brazilian artificial insemination centers using a commercial kit for DNA extraction (RTP Bacteria DNA Mini Kit (Invitek®), to improve it for extracting bacterial DNA from semen and to analyze its applicability in laboratory routine. Bacterial DNA was extracted and quantified by agarose gel electrophoresis. We also intended to realize polymerase chain reaction (PCR) using primers B4 and B5 for amplification of Brucella spp. DNA and primers Lep 1 e Lep 2 for Leptospira spp. DNA. The extraction kit was successfully optimized and all of 96 examined samples were negative for any bacterial DNA. Results could be useful to establish alternative measures of sanitary control in semen donors and to allow the supplying of genetic material free of pathogens, increasing sanitary status of bovine reproduction in Brazil
52

Avaliação dos parâmetros seminais de indivíduos inférteis em uso de polivitamínico e polimineral

Maia, Fernanda Alves [UNESP] 09 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-09Bitstream added on 2014-06-13T18:39:54Z : No. of bitstreams: 1 maia_fa_me_botfm.pdf: 761192 bytes, checksum: af7cd1654f8ff045bdb288b848b037dc (MD5) / A infertilidade é definida pela inabilidade de engravidar após 12 meses ou mais de coito regular não protegido. O uso de polivitamínico e polimineral parece influenciar na qualidade seminal. Dados da literatura sobre o uso oral isolado ou combinado desses micronutrientes na melhoria dos parâmetros seminais e eventual fertilidade são controversos e escassos. Analisar os parâmetros seminais de indivíduos inférteis em uso de polivitamínico e polimineral e compará-los com indivíduos normais, comprovadamente férteis sem uso destas substâncias. Foram analisados os parâmetros Seminais de 57 casais inférteis acompanhados no ambulatório de esterilidade do Hospital das Clínicas da Faculdade de Medicina de Botucatu, no período de 2003 a 2007. Nos indivíduos inférteis a análise seminal foi realizada antes e com 90 dias de micronutrientes por via oral os quais foram comparados com 50 indivíduos saudáveis comprovadamente férteis sem uso destas substâncias. A avaliação do sêmen foi feita de acordo com os critérios da Organização Mundial de Saúde - OMS (1999) e morfologia de Kruger et al. (1986). A análise estatística foi feita utilizando os testes t de Student, Mann-Whitney e Wilcoxon, considerando um nível de significância de 5%. Os indivíduos inférteis e os comprovadamente férteis apresentaram similaridade quanto a idade (31,0±5,6 versus 30,3±6,5) (p=0,55) e ao tabagismo (29,8% versus 22,0) (p=0,36). Nos indivíduos inférteis, o uso desses micronutrientes aumentou significativamente a morfologia tanto pelos critérios estabelecidos pela OMS (18,3±9,6 para 22,6±11,8) (p=0,006) e por Kruger (6,9±4,1 para 9,1±5,2) (p=0,002). Verificou-se que os homens inférteis antes do uso de micronutrientes quando comparados aos férteis apresentavam significantemente uma menor concentração de espermatozóides/ml (68,0[37,8;101,2]... / Infertility is defined as the inability to become pregnant after 12 months or more of regular unprotected intercourse. The use of multivitamin/multimineral supplements seems to influence semen quality. Data on the isolated or combined use of these micronutrients to improve semen parameters and eventual fertility are controversial and scarce. To assess semen parameters in infertile individuals using multivitamin and multimineral supplements in comparison with healthy proven fertile individuals not using these substances. Semen parameters were evaluated in 57 infertile couples followed up in the Sterility Outpatient Clinic of Botucatu Medical School between 2003 and 2007. Semen analysis was performed before and after 90 days of oral micronutrient use in infertile individuals that were compared with 50 healthy proven fertile individuals not using these substances. Semen was evaluated according to the recommendations of the World Health Organization- WHO (1999) and the criteria described by Kruger et al. (1986). Statistical analysis was carried out using Student’s t test and the tests of Mann-Whitney and Wilcoxon with significance set at 5%. Infertile and proven fertile individuals showed similar age (31.0±5.6 versus 30.3±6.5) (p=0.55) and smoking status (29.8% versus 22.0) (p=0.36). In infertile individuals, the use of micronutrients significantly improved morphology according to the criteria of WHO (18.3±9.6 to 22.6±11.8) (p=0.006) and Kruger (6.9±4.1 to 9.1±5.2) (p=0.002). Before micronutrient use, infertile individuals compared with fertile males showed lower spermatozoa/ml concentration (68.0[37.8;101.2] versus 96.5[49.0;144.2]) and vitality (85,4±9,2 versus 89.6±6.9) and higher leukocyte count (600.0 [300.0;121.5] versus 350.0[100.0;675.0]). In infertile individuals using multivitamin and multimineral supplements, semen parameters... (Complete abstract click electronic access below)
53

Effect of heterologous seminal plasma and semen extenders on motility of frozen-thawed ram sperm

Mataveia, Gracinda Andre 14 May 2008 (has links)
Frozen-thawed ram semen crosses the cervix poorly, necessitating laparoscopic insemination. Acceptable fertility can be achieved with frozenthawed ram semen deposited at the external cervical opening if ram seminal plasma is added. Homologous seminal plasma improves the fertility of frozen-thawed sperm of boars and dogs. Heterologous seminal plasma may have effects as well; the addition of bovine seminal plasma increases the ability of buffalo sperm (Syncerus caffer) to fertilize bovine oocytes in vitro. The aim of the current study was to compare the effects of seminal plasma of rams and bulls, dog prostatic fluid, protein-free TALP, TrilEq (Triladyl with 0.5 ml of Equex STM paste added to each 100 ml) and skim milk upon longevity and percentages of progressively and aberrantly motile frozenthawed ram sperm. Three ejaculates from each of 6 rams (2 Dorpers, 2 Döhne merinos, and 2 merinos), aged 2 to 4 years, were extended in TrilEq, pooled and frozen as a single batch per ram at 200 × 106/ml in 0.25 ml straws. Seminal plasma of rams was obtained from the same rams, while seminal plasma of five bulls were obtained by centrifugation of their ejaculates and dog prostatic fluid consisted of the post-sperm fractions of the ejaculates of 5 dogs. Within a 10 species, the seminal plasma or prostatic fluid from different donors was pooled and frozen in aliquots at −18 °C. The 108 straws (6 rams, 6 diluents, 3 replicates) were thawed in random order. Once thawed, a straw was emptied into a tube with 0.85 ml of the appropriate medium at 37 °C and kept at that temperature for 6 h. The percentage of progressively motile sperm was estimated at ×200 magnification immediately (time zero) and 2, 4 and 6 h after thawing. One person thawed the semen and prepared motility specimens, while another performed all motility evaluations. Data were evaluated by means of repeated-measures ANOVA, with rams as subjects and time and medium as fixed effects. Non-significant interactions were removed from the model. Pairwise comparison of means was done by means of Bonferroni's test (P < 0.05). The model included Ram, Time, Medium, and Ram × Medium, and Time × Medium interactions, which were all significant (P < 0.01). Mean progressive motility decreased from each time to the next and were 39.0% (0 h), 26.0% (2 h), 19.6% (4 h) and 12.6% (6 h); SEM 1.38%, n = 108. Mean motility was higher for skim milk (39.9%) than for all other media except TrilEq (27.7%), which was better than bull seminal plasma (13.0%), whereas TALP (20.5%) and ram seminal plasma (21.9%) were similar to TrilEq and bull seminal plasma (SEM 2.85%, n = 72). The interactions (Ram × Medium or Time × Medium) were mainly due to dog prostatic fluid, ram seminal plasma, TrilEq, and TALP, while milk resulted in the best and bull seminal plasma in the lowest motility. This study shows that heat-treated skim milk maintains progressive motility of frozen-thawed ram sperm better than dog prostatic fluid and seminal plasma of bulls and rams, TrilEq and protein-free TALP. In contrast to ram seminal plasma, skim milk is known to result in poor fertility of frozenthawed ram semen after cervical insemination. It would thus appear that maintenance of progressive motility in vitro may be a poor indicator of fertility after cervical insemination. / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2006. / Production Animal Studies / MSc / unrestricted
54

Evaluation of suitable chilled, extended semen preservation time and their effects of different artificial insemination techniques on the fertility of indigenous Venda goats

Monyeleote, Vukosi 18 September 2017 (has links)
MSCAGR (Animal Science) / Department of Animal Science / The aims of the study were to evaluate the effects of dilution and chilled storage time on the quality of semen, and of different artificial insemination techniques on fertility in artificially inseminated indigenous Venda does. Fresh semen was collected using an artificial vagina from three Boer bucks aged 4±1.55 years once every four days during July and August 2016. Semen was pooled and samples were divided into two equal parts, which were extended using Biladyl® extender at ratios of 1:5 and 1:10 v/v (semen to extender), before refrigeration for 120 hours at 5 °C. The fresh undiluted semen and freshly extended semen were evaluated in six replicates for sperm motility, live-dead and sperm morphology using the Sperm Class Analyzer (SCA). Extended semen continued to be evaluated at 24 hour intervals for 120 hours. Ninety indigenous Venda does were obtained from different flocks in the Vhembe district and kept intensively in one 10 m x 40 m pen at the University of Venda experimental farm in the goat feedlot. The does were fed and watered ad libitum. After acclimatization for 14 days, estrus was synchronized using a controlled internal drug release (CIDR) containing 0.3 g of progesterone. Upon removal of the CIDR, does were injected 10 mg of PGF2α (Lutalyse® dinoprost tromethamine) Sterile Solution. At 24 hours after the removal of the CIDR, the does were injected intramuscularly with 300 international units (IU) of equine chorionic gonadotrophin (eCG). Forty eight hours after the removal of the progesterone, freshly collected and diluted (1:5 ratio ~150x106 sperm/ml), five day-stored semen were used to inseminate the does using cervical (CAI), trans-cervical (TAI), and laparoscopic artificial (LAI) insemination methods in a complete randomized design (CRD) with a 2 X 3 factorial arrangement of the treatments with 15 replications per treatment. The does were tested for pregnancy after 30 days using ultrasonography. Analyses of variance was performed on the pregnancy, kidding rates and on prolificacy using the GLM procedure of Minitab (Minitab 2013). Significant differences in all motility parameters were observed between the extension ratios and storage time (P<0.01). There were significant interactions between the extension ratio and storage time (P<0.05) on the sub-population of sperm cells with non-progressive motility (NON-P). Significant (P<0.01) interaction was observed between the semen extension ratio and storage time on medium and slow spermatozoa (P<0.01). The method of insemination did not (P>0.05) affect fertility, though both pregnancy and kidding rates numerically decreased in the order laparoscopic insemination (LAI)≥ trans-cervical insemination (TAI)≥ cervical insemination (CAI). Overall, 71% kidding rate was achieved.
55

Factors affecting the quality of semen of A.I. dairy bulls in South Africa

Vilakazi, David Mxolisi 02 September 2005 (has links)
The primary objective of this research was to study the effects of breed, age, season, and their interactions on semen morphological characteristics. The study was done on 329 bulls (271 Friesland and 58 Jersey) aged 12, 24, 36,48, 60, 72, 84, 96 and> 96 months. The collection of semen was carried out using the artificial vagina method in all four seasons of the year. Spermatozoa were screened for the percentages normal sperm, percentage and total major defects such as knobbed acrosome, pyriform, abnormal lose head, dag defects, nuclear vacuole, degenerative heads, mid-piece reflexes, percentages and total minor defects such as normal lose heads, distal droplets, curled end-piece, lose acrosome. Statistical analyses of the data were done using the general linear model (GLM) procedure of the Statistical Analyses System (SAS, 1999). The results of the study indicate that breed did not significantly affected the percentage normal sperm and percentage major sperm defects, but significantly affected the percentage minor defects (P = 0.01). The Least square means (LSM±SE) for the percentage normal sperm, major defects and minor defects in Friesland and Jersey bulls were 80.6 ±1.06%; versus 78.9±2.31 %; 14.8±0.90% versus 15.0± 2.62%, 5.1±0.43% versus 7.6±0.94%, respectively. The results obtained show that the prevalence of sperm defects that differed significantly between breeds was higher in Jersey bulls compared to Friesland bulls. The results of the study indicated the percentage of normal sperm to differ (P = 0.01) with season. The percentage of normal sperm during the summer, autumn, winter and spring, were 72.8±1.6%, 79.4±2.2%, 82.5±2.4% and 84.4±2.4% respectively. Season also affected the percentage of major defects (P = 0.01) and percentage of minor defects (P = 0.03). The results demonstrate that even though there was a higher variation in sperm morphology with season, better sperm morphology was recorded in spring and winter than summer and autumn. Results also indicate the percentage of normal sperm (P = 0.05) and major defects (P = 0.01) to be affected significantly by age. On the other hand, the percentage of minor defects did not differ significantly with age. Bulls of 36-48 months of age showed better semen quality than bulls older than 72 months and bulls younger than 36 months. The percentage of major defects, particularly the incidence of major defects such as knobbed acrosomes, pyriforms, dag defects and broken flagella were significantly affected by the interaction between age and breed (P = 0.05) and age and season (P = 0.05). There was an increase in the susceptibility to these sperm defects in Jersey bulls with an increase in age, while no variation was observed in Friesland bulls. With age and season combined, young bulls recorded poor semen morphology during winter, while old bulls showed poor morphology during summer. In conclusion, the study suggested that breed, age and season and their interactions are important sources of variation in sperm morphology. For a successful AI programme, semen collection should be done at the age of 36-48 months for both breeds. It is therefore recommended that age, breed and season should be given urgent attention in any bull management system employed in South Africa in order to obtain the best semen quality. / Dissertation (M Inst Agrar (Animal Production))--University of Pretoria, 2003. / Animal and Wildlife Sciences / unrestricted
56

Effect of selection for fertility of frozen-thawed semen on fertility and spermatozoal motility of fresh and stored non-frozen chicken semen.

Yousif, Yousif Fathalla. January 1982 (has links)
No description available.
57

The effects of an organic phosphate compound (Bayer 21

Milleret, Roy Joseph. January 1959 (has links)
Call number: LD2668 .T4 1959 M55
58

Role of seminal fluid in sexual transmission of HIV-1

Kim, Louise U. January 2001 (has links)
No description available.
59

Dietary supplementation of omega-3 fatty acids and subsequent effects on fresh, cooled, and frozen seminal characteristics of stallions

Grady, Sicilia Tatiana 15 May 2009 (has links)
The use of cooled and frozen/thawed semen offers many advantages to breeders. However, many stallions produce spermatozoa that are unable to endure the stresses of cooling/storage and freezing/thawing. Improving the quality and viability of equine spermatozoa via appropriate dietary manipulation could make these stallions commercially viable for cooling or cryopreservation. To evaluate whether spermatozoa quality and viability can be improved by supplementation of omega-3 fatty acids, and if improvements can be made by altering the sources of these fats, nine miniature stallions were placed into 1 of 2 treatment groups and fed either a fish- or algae/flaxseed-based supplement which was added to the basal concentrate. Motion characteristics, membrane integrity and morphology of spermatozoa in fresh, cooled/stored (24 and 48 h), and frozen/thawed semen samples were analyzed. When comparing spermatozoa obtained from stallions in each treatment, no differences were found (P > 0.05) in motility, percentage of membrane intact spermatozoa, and percentage of morphologically normal spermatozoa of stallions. Overall, omega-3 supplementation did not appear to have a beneficial effect on offsetting the harmful effects of the cooling and freezing processes. However, when analyzing the data of one stallion that had < 40% progressive motility (PMOT) after 24 h of cooling and storage, a significant increase was observed in total motility, and progressive motility of fresh and 24 h cooled/stored spermatozoa was observed when supplemented with the fish-based supplement. Thus, omega-3 fatty acid supplementation may be most beneficial for stallions that produce lower quality ejaculates. However, further studies should be conducted, with a larger sample size, in order to substantiate these findings.
60

Effect of the acidic buffer 2-[n-morpholino] ethanesulfonic acid on frozen-thawed bull semen

Botha, Alma Ester. January 2010 (has links)
Thesis (MSc (Production Animal Studies, Veterinary Science))--University of Pretoria, 2008. / Includes bibliographical references. Also available in print format.

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