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Orientador: Wilma de Grava Kempinas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T09:29:05Z (GMT). No. of bitstreams: 1 Fernandez_CarlaDalBianco_M.pdf: 4031573 bytes, checksum: 22cce9ddde55fbd43e3ae5addb295ff4 (MD5) Previous issue date: 2006 / Resumo: O epidídimo é um órgão do sistema reprodutor masculino, onde os espermatozóides passam pelo processo de maturação, adquirindo motilidade e capacidade fértil. O tempo de trânsito espermático pelo epidídimo (número de dias necessários para os espermatozóides serem transportados pelo órgão) parece ter um papel importante na maturação dos espermatozóides, e uma alteração desse tempo pode prejudicar o processo. Trabalhos da literatura mostram que a exposição de ratos machos a substâncias estrogênicas, como o dietilestilbestrol (DES), afeta o trato reprodutor masculino e provoca uma aceleração do tempo de trânsito dos espermatozóides pelo epidídimo, comprometendo a fertilidade nestes animais. O objetivo do presente trabalho foi avaliar a influência da alteração do tempo de trânsito dos espermatozóides no epidídimo sobre parâmetros espermáticos e fertilidade em ratos, bem como o papel da testosterona nestas alterações. Para tanto, dois modelos experimentais foram utilizados: o DES foi administrado para acelerar o tempo de trânsito espermático nos ratos, e a guanetidina, para retardá-lo, através da simpatectomia química na genitália interna masculina. Ratos machos adultos, da variedade Sprague-Dawley, foram divididos em quatro grupos experimentais: 1) tratado com injeções subcutâneas de dietilestilbestrol (DES), diluído em óleo de milho, na dose de 10µg/rato/dia, durante 12 dias; 2) tratado com injeções intraperitoneais de sulfato de guanetidina, dissolvido em solução salina, na dose de 6,25mg/kg/dia, por 12 dias; 3) mesmo tratamento do grupo 1, mais um suplemento androgênico, através de implantes de cápsulas siliconizadas e preenchidas com testosterona; 4) grupo controle, que recebeu as soluções veículo. O tratamento com guanetidina retardou o tempo de trânsito espermático na cauda do epidídimo, aumentando, assim as reservas de espermatozóides nessa região. Por outro lado, a exposição ao DES acelerou o trânsito espermático no epidídimo, diminuindo o número de espermatozóides na cabeça-corpo e na cauda, e reduziu a motilidade dos espermatozóides. Em ambos os casos, a produção espermática não foi alterada. A reposição de testosterona restaurou o tempo de trânsito espermático a valores próximos da normalidade, uma vez que foram maiores que o do controle. A reposição de testosterona também corrigiu a alteração na motilidade dos espermatozóides. Os animais expostos ao DES apresentaram uma tendência de prejuízo da fertilidade após o procedimento de inseminação artificial in utero, utilizando espermatozóides colhidos da região proximal da cauda do epidídimo. Assim, concluiu-se que a aceleração do tempo de trânsito espermático no epidídimo pareceu prejudicar a maturação normal dos espermatozóides nos ratos, diminuindo a qualidade espermática e a capacidade fértil, de maneira andrógeno-dependente / Abstract: The epididymis is an organ of the male reproductive system where sperm undergoes the maturation process, acquiring motility and fertility capacity. The epididymal sperm transit time (number of days necessary for the sperm to be transported through the organ) seems to have an important role in sperm maturation, and it seems that an alteration of the duration of this transit can harm the process. Data from the literature show that the exposure of male rats to estrogenic substances, such as diethylstilbestrol (DES), affects the male reproductive system and provokes an acceleration of sperm transit in the epididymis, damaging the fertility of the animals. The aim of present work was to evaluate the influence of altered sperm transit time through the epididymis on sperm parameters and fertility of rats, as well as the role of testosterone in the alterations. For this, two experimental models were used: DES was administered to the rats to accelerate the sperm transit time, and guanethidine, to delay it, through a selective chemical sympathectomy of the male internal organs. Sprague- Dawley adult male rats were divided into four experimental groups: 1) treated with sc injections of DES, for 12 days, 10µg/rat/day, dissolved in corn oil; 2) treated with guanethidine sulfate via ip injections, for 12 days, at the dose of 6.25mg/kg/day, dissolved in saline solution; 3) same treatment as group 1, plus androgen supplementation, using testosterone-filled subcutaneous implants; 4) control animals received the vehicles. Guanethidine treatment delayed the sperm transit time through the epididymal cauda, provoking an increase in the sperm reserves in this region. On the other hand, exposure to DES accelerated the sperm transit time in the epididymis, decreasing the sperm density in both epididymal regions, the caput-corpus and cauda, and diminishing sperm motility. In both cases sperm production was not altered. Testosterone supplementation was able to restore the transit time to values close to normality, since they were higher than in the control rats. The same occurred in relation to sperm motility. Rats exposed to DES presented a trend toward lower fertility after in utero artificial insemination using sperm collected from the proximal cauda epididymidis. Thus, it was concluded that the acceleration of sperm transit time seemed to harm the normal sperm maturation in the rat, decreasing / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural

Exploring the genetics of the efficiency of fertile AI dose production in rabbits The general aim of this thesis has been to analyse sources of variation for some of the most important components of fertile artificial insemination (AI) dose production in order to explore the interest and limitations of different strategies for their genetic improvement in a paternal line of rabbits selected for growth rate. These components refer to seminal production and quality traits, being considered the male reproductive performance (fertility and prolificacy) as the final expression of the effect of the seminal characteristics and the effect of the interaction among them and with the female. Genetic analyses of the seminal traits involved in AI dose production and growth rate were modelled using threshold and linear multiple-trait mixed models. Relationship between fertility and pH of the semen was analysed either using mixed or recursive mixed models. Male and female genetic contributions to fertility were estimated using additive or product threshold models and both models were compared by its ability of predicting fertility data. Existence of genotype x artificial insemination conditions for male effect on fertility and prolificacy was estimated under a Character state model. Finally, the product threshold model was used for estimating separately the effect of the environmental temperature on male and on female contributions to fertility. All inferences of this thesis have been done under a Bayesian approach. Male libido and variables related to the quality of the ejaculate such as presence of urine and calcium carbonates in the ejaculate, individual sperm motility, semen pH and suitability for AI of the ejaculate (which involves the subjective combination of several semen quality traits) were found to be lowly heritable, but repeatable. / Tusell Palomero, L. (2011). Exploring the genetics of the efficiency of fertile AI dose production in rabbits [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11842 / Palancia

Se utilizarán eyaculados procedentes de machos de la línea R (línea de conejos seleccionada por velocidad de crecimiento durante el periodo de engorde)alojados en diferentes centros de inseminación artificial. Una vez recuperados los eyaculados se procederá a su valoración y una muestra de todos ellos será crioconservada. La calidad seminal será de nuevo valorada tras el proceso de congelación. Junto con los anàlisis seminales se utilizarán los datos de crecimiento y pedigree de los machos y de todos los animales de la línea R desde su fundación para estimar por un lado los parámetros genéticos de las variables relacionadas con la producción y calidad de dosis seminales en fresco y tras un proceso de crioconservación y la correlación genética existente entre las variables seminales anteriormente citadas y la velocidad de crecimiento. A su vez se estimará mediante un modelo recursivo la relación entre las variables seminales en fresco y tras la descongelación. / The general aim of this thesis was to study the genetic determinism for some traits related to artificial insemination (AI) dose production of fresh and frozen-thawed semen, in order to explore the interest and limitation of different strategies for their genetic improvement in a paternal line of rabbits selected for growth rate during the fattening period (28-63 days). In chapter 1, genetic parameters of sperm production traits are estimated as well as the genetic relationship with daily gain (DG). The heritabilities (h2) of the semen traits were 0.13±0.05, 0.08±0.04 and 0.07±0.03 for ejaculate volume (V), sperm concentration (CN) and sperm production (PROD) per ejaculate, respectively. A favourable and moderate genetic correlation was observed between V and DG (0.36±0.34). From this chapter it may be concluded that if a seminal trait is to be included as a selection objective, a useful one could be sperm production, as it is a trait in which both volume and concentration are included. Moreover, there is currently no evidence to suggest that selection for DG in rabbits will affect sperm production adversely. The aim of chapter 2 was to explore the genetic determinism of some sperm quality traits and their genetic relation with the selection criteria of the paternal rabbit line. The heritabilities (h2) of semen quality traits commonly evaluated in a classic spermiogram were 0.18, 0.19 and 0.12 for NAR (%, percentage of sperm with intact acrosome), ANR (%, percentage of sperm abnormalities) and MOT (%, percentage of total motile sperm cells) respectively. We also estimated the h2 of some motion CASA parameters 0.09, 0.11, 0.10, 0.11, 0.11 and 0.11 for VAP (µm/s; average path velocity), VSL (µm/s; straight-line velocity), VCL (µm/s; curvilinear velocity), LIN (%, linearity index), ALH (µm; amplitude of the lateral head displacement), STR (%, straightness). Genetic correlations between DG and semen traits showed a high HPD95% (interval of highest density of 95%). However there is some consistent evidence of the negativity of the genetic correlations of DG with NAR and MOT (-0.40 and -0.53, respectively). Chapter 3 aims to determine the repeatability and heritability of sperm head characteristics: width (W, ¿m), area (A, ¿m2),length (L, ¿m) and perimeter (P, ¿m), and explore the relationships between them and with the selection objective (DG). The results obtained showed that sperm head dimensions are heritable (ranged between 0.2 and 0.29). The genetic correlations between sperm traits were always high and positive (between 0.72 and 0.90), with the exception of L-W genetic correlation, which was moderate. Regarding the genetic correlations between DG and sperm head characteristics, the resulting means ranged from -0.09 for L-DG to -0.43 for W-DG, showing consistent evidence of the negativity of the genetic correlations. The environmental and male effects that could have an influence on sperm freezability are studied in Chapter 4. Six different traits were evaluated: sperm concentration (CONC, 106spermatozoa/mL), acrosome integrity in fresh (NAR, %) and frozen-thawed semen (Nar-FT, %), sperm motility in fresh (MOT, %) and frozen-thawed semen (Mot-FT, %) and the percentage of viable sperm in frozen-thawed semen (Live-FT, %). In addition, two synthetic traits were computed: the relative reduction of acrosome integrity (Rnar, %) and relative reduction of motility (Rmot, %) after the freezing-thawing process. A multiple-trait recursive model was used to analyse the relationships between the semen traits considered. For the fixed effects studied, the season had the highest impact on post-thaw semen characteristics. Results of the analysis of recursive coefficients showed that fresh semen concentration and motility influence the future freezability of the semen. All traits studied presented moderate repeatabilities, ranging from 0.11 to 0.38. These results provide conclusive evidence that sperm freezability in rabbits could be heritable. Regarding male correlations, there were large positive male correlations between fresh traits (rm=0.77-0.57), as well as between direct frozen-thawed traits (rm=0.72-1). Male effects on fresh and direct frozen-thawed traits were generally positively correlated. This correlation was moderate to high for MOT with all frozen-thawed traits (rm=0.41-0.74) and for Mot-FT and all fresh traits (rm=0.5-0.74); these results suggest that these traits could be genetically related. The final chapter of this thesis focused on estimating the heritability of semen freezability traits and estimating the genetic correlation between frozen-thawed sperm traits and the growth rate in a paternal rabbit line. Estimated heritabilities showed that frozen-thawed semen traits are heritable (ranged between 0.08 and 0.15). In the case of Live-FT, the estimated heritability is the highest and suggests the possibility of effective selection. After the study of genetic correlations, it seems that DG was negatively correlated with sperm freezability, but due to the high HPD95% no further conclusions could be drawn. More data should be included in order to obtain better accuracy for the estimates of these genetic correlations. If the results obtained in the present study were confirmed, it would imply that selection for DG could alter sperm cell membranes or seminal plasma composition, both components related to sperm cryoresistance. / Lavara García, R. (2013). Genetics of fresh and frozen-thawed semen traits and their relationship with growth rate in rabbits [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/31657 / TESIS

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Four experiments were conducted to evaluate the viability and fertility of bovine spermatozoa encapsulated in microcapsules and microgels. In Experiment I, one of two morphologically distinct sperm types i.e. marker or unmarked bull spermatozoa (100 x 10⁶ sperm/bull) were encapsulated in protamine sulfate microcapsules and simultaneously inseminated with the reciprocal sperm type unencapsulated. Insemination of both sperm types unencapsulated served as a control. Accessory sperm embedded in the zona pellucida were counted and morphologically classified 6 to 7 d post insemination. From microencapsulated inseminates, accessory sperm populations did not increase over the unencapsulated controls, but contributed 25.7% of the accessory sperm population. ln Experiment 2, an in vitro study was performed to evaluate the maintenance of viability for bovine spermatozoa encapsulated in PIPES, HEPES, or saline microgels. Neat semen was pooled from five bulls (50 x 10° sperm/bull), encapsulated in alginate microgels, and incubated at 37 C for 8 h. The unencapsulated control displayed greater maintenance of viability for percent intact acrosomes and motility when compared to all treatments. By 8 h incubation, PlPES and HEPES were not significantly different, but demonstrated greater maintenance of viability when compared to saline microgel treatments. In Experiment 3, PIPES microgels were heterospermically inseminated with equal numbers (20 x l0⁶ sperm/bull) of frozen-thawed marker bull and normal bull spermatozoa as explained in Experiment 1. Microencapsulated treatments contributed significantly lower numbers of accessory sperm when compared to unencapsulated controls. In Experiment 4, one of the two morphologically distinct sperm types (20 x l0⁶ frozen-thawed sperm/bull) were encapsulated in protamine sulfate microcapsules and the reciprocal sperm type was encapsulated in PIPES microgels. A total of 21 accessory sperm were recovered from 30 embryos which demonstrates the ability of microencapsulated spermatozoa to fertilize an oocyte. / Master of Science

A series of in vitro studies were conducted to evaluate the effect of poly-l-lysine concentration, molecular weight, and encapsulation temperature on the post encapsulation survivability of spermatozoa. Viability of spermatozoa encapsulated at 2012 C using four poly-l-lysine concentrations (.05%, .15%, .25%, and .35%) did not differ over the 8 h incubation period. However, the viability of each of the four treatments was lower than that of the unencapsulated control (p<.05 and p<.01; percentage motility and percentage intact acrosomes, respectively), indicating spermatozoal damage occurred during the encapsulation process. Capsule wall thickness and integrity for the .15%, .25%, and .35% concentrations were greater (p<.Ol) than that of the .05% capsules. / Master of Science

Made available in DSpace on 2014-06-11T19:29:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-26Bitstream added on 2014-06-13T19:38:31Z : No. of bitstreams: 1 crespilho_am_me_botfmvz.pdf: 507525 bytes, checksum: a1c92f545e77b50838125fbea8dfddd6 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A despeito das inúmeras variáveis que influenciam direta e indiretamente a fertilidade das fêmeas bovinas, a qualidade das amostras seminais exerce um papel importante na determinação das taxas de concepção dos programas de inseminação artificial. Os objetivos dessa pesquisa foram comparar a efetividade de dois diluidores de criopreservação de sêmen bovino no processamento de amostras seminais apresentando diferentes concentrações espermáticas em relação aos índices de congelabilidade determinados laboratorialmente (Experimento I) e as taxas de concepção proporcionadas por cada metodologia quando utilizada em programas de inseminação artificial em tempo fixo (IATF) em bovinos (Experimento II). No Experimento I foram utilizados 14 ejaculados de diferentes touros da raça Nelore. Cada ejaculado foi fracionado em oito alíquotas iguais, submetidas a criopreservação com os diluidores Tris-gema de ovo-frutose (meio TRIS) e MKA nas concentrações de 12, 25, 50 e 100 milhões de espermatozóides totais por mililitro de meio, formando oito grupos experimentais em função das variáveis diluidor e concentração. As amostras foram descongeladas a 46 ºC por 20 segundos, avaliando-se os padrões de motilidade através do método computadorizado (CASA), integridade de membrana plasmática (IMP), resistência ao teste de termorresistência rápido (TTR) e taxa de recuperação e IMP após seleção espermática pela técnica de swim-up. Para o Experimento II foram selecionados sete touros utilizados no Experimento I, obtendo-se um ejaculado de cada animal por eletroejaculação... / Although there are many variables which directly or indirectly influence female bovine fertility, the quality of sperm samples plays a important role in the determination of conception rates in artificial insemination programs. The aim of the present study was to compare the efficiency of two bovine semen extenders for sperm freezing with different spermatic concentrations in the freezability determined by lab tests (Experiment I), and conception rates after fixed time artificial insemination (FTAI; Experiment II). In Experiment I 14 ejaculates of different Nelore bulls were used. Each ejaculate was splitsampled in to eight equal parts and then submitted to cryopreservation with Tris-egg yolk fructose (TRIS) and MKA extenders, at concentrations of 12, 25, 50 and 100 millions spermatozoa per milliliter forming eight experimental groups. The samples were thawed at 46 ºC for 20 seconds, and the following parameters were evaluated: sperm motility and movement (by computer-assisted semen analysis - CASA), sperm membrane integrity (SMI), resistance to the fast thermoresistance test (TT), recovery rate and sperm membrane integrity after sperm selection through swim-up technique. Seven of 14 bulls used in Experiment I were selected for Experiment II, and semen was collected from each of the animals by electroejaculation. The seven ejaculates obtained were mixed (semen pool) and cryopreserved, thus forming eight experimental groups according to the freezing extenders and sperm concentrations/straws: TRIS 12, 25, 50 and 100, and MKA 12, 25, 50 and 100...(Complete abstract, click electronic address below)

Thesis (M. Tech. (Agric. Animal Prod.)) -- Central University of technology, Free State, 2009 / The objective of this study was to evaluate the viability of semen extended in “Umqombothi” (UMQ) and compare with Beltsville Thawing Solution (BTS) and unextended semen (UNX). Twelve large white boars and twelve large white sows were used in this experiment. The following sperm characteristics were measured; sperm motility percentage, live sperm, sperm concentration, abnormal sperm percentage and semen pH of (UNX), (UMQ) and (BTS) and compared, fertility parameters namely; non-return rate percentage, farrowing rate, total piglets and live piglets were also measured and compared. The results from the study showed a significant difference (p<0.05) in sperm motility between (UNX), (UMQ) and (BTS) whereby (UMQ) had the highest percentage of motile sperm which was followed by (BTS) and (UNX) having the lowest percentage of motile sperm, however the results also showed that sperm motility and live sperm percentage of semen stored at 4°C differed significantly (p<0.05) from sperm motility and live sperm percentage of semen stored at 25°C whereby sperm motility and live sperm percentage of semen stored at 25°C were higher than sperm motility and live sperm percentage of semen stored at 4°C. Nevertheless no significant difference in sperm concentration and semen pH was found when semen stored at 4°C and 25°C were compared. However were time of semen collection of 9:00 and 15:00 were compared no significant differences in sperm motility percentage, live sperm percentage, sperm concentration, abnormal sperm percentage and semen pH were observed. The study also revealed a significant difference (p<0.05) in non-return rate, farrowing rate, total piglets and live piglets between semen stored at 25°C and 4°C of which the results explain that semen stored at 25°C had a higher percentage of non-return rate , farrowing rate, total piglets and live piglets, however, Under (UNX) collected at 9:00 and 15:00 that there was no significant difference in no-return rate percentage, farrowing rate, total piglets and live piglets was observed when two times of semen collections were compared. Under (UMQ) collected at 9:00 and 15:00 there was also no significant difference in non-return rate percentage, farrowing rate, total piglets and live piglets observed when two times of semen collections were compared. Under (BTS) collected at 9:00 and 15:00 there was also no significant difference in non-return rate percentage, farrowing rate, total piglets and live piglets observed when two times of semen collections were compared. Nevertheless were semen extenders were compared (UNX) collected at 9:00 and 15:00 differed significantly (p<0.05) from (UMQ) and (BTS) collected at 9:00 and 15:00 whereby (UNX) had the lowest percentage of non-return rate, farrowing rate, total piglets and live piglets.

Thesis (M. Tech. (Agriculture)) - Central University of Technology, Free state, 2013 / The study was carried out to establish whether or not a decrease in the progesterone concentration of an intravaginal device used to synchronize oestrous in Beefmaster heifers and cows would lead to an increase in conception rates. The study evaluated the effect of different intravaginal progesterone device doses on the conception rates of Beefmaster cows and heifers following fixed time artificial insemination (FTAI). A total of 100 stud Beefmaster cows (Cow group) and 100 stud Beefmaster heifers (Heifer group) were used in the study. The animals were year round grazing residents of the farm Oribilaagte near the town of Vrede in the Free State province of South Africa. The Cow and Heifer groups were split into four experimental groups, respectively, and treated with either a 0.5 g, 1.0 g, 1.9 g or 1.9 g re-used intravaginal progesterone device during the spring synchronization program (P4 device insertion and 2 mg i.m. oestradiol benzoate treatment on d 0, 250 μg s.c. PGF2_ treatment on d 7, P4 device removal on d 8, 1 mg i.m. oestradiol benzoate treatment on d 9, and FTAI on d 10). Blood samples were taken on the day of intravaginal insert removal (d 8), and on the day of FTAI (d 10), to monitor the blood serum P4 concentrations (solid phase RIA analysis) between the experimental groups. The experimental groups were examined for pregnancy 5 months post AI by means of rectal palpation. The Cow group recorded a pregnancy rate of 65%, 75%, 67% and 68% for the 0.5 g, 1.0 g, 1.9 g and 1.9 g re-used intravaginal progesterone device groups respectively. The Heifer group recorded a pregnancy rate of 19%, 39%, 41% and 47% for the 0.5 g, 1.0 g, 1.9 g and 1.9 g re-used intravaginal progesterone device groups respectively. The study concluded that a decrease in the progesterone concentration in the intravaginal device did not affect the serum progesterone concentrations in the Heifer and Cow groups on the day of the FTAI, and did not negatively affect the synchronization program. The study further concluded that, although a decrease in the progesterone concentration in the intravaginal device did not statistically influence the conception rates in the Heifer and Cow groups, the Cow group did record a higher numerical conception rate when the progesterone concentrations in the intravaginal devices were reduced.