Thesis (M.A.)--Trinity International University, 2000. / Abstract. Includes bibliographical references (leaves 67-72).

Thesis (M.A.)--Trinity International University, 2000. / Abstract. Includes bibliographical references (leaves 67-72).

Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains viii, 113 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 88-113).

Made available in DSpace on 2014-06-11T19:35:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-11Bitstream added on 2014-06-13T20:06:39Z : No. of bitstreams: 1 oliveira_mef_dr_jabo.pdf: 918161 bytes, checksum: 9751db33ae3b228fbba2eeae5557b579 (MD5) / Fundação para o Desenvolvimento da UNESP (FUNDUNESP) / Foram realizados dois experimentos, no primeiro, 70 ovelhas foram submetidas a um dos dois protocolos de sincronização do estro, em três períodos estacionais (Fatorial 2x3; Anestro: G-1CIDR, n=12 e G-2CIDR, n=11; Transição: G-1CIDR, n=12 e G-2CIDR, n=12; Ciclicidade: G-1CIDR, n=11 e G-2CIDR, n=12). O estro foi sincronizado com um dispositivo intravaginal de progesterona (P4; CIDR) por 14 dias. No G-2CIDR, o CIDR foi trocado por um novo no D7 (D0 = início do protocolo). No D0 e 14, 2,5 mg de um análogo da PGF2 (dinoprost) foram administradas, i.m., em todas as ovelhas. Exames ultrassonográficos dos ovários, por via transretal, foram realizados diariamente durante os protocolos (14 dias). Os dados foram analisados por regressão logística utilizando o Proc GLIMMIX do SAS (P<0,05). As ovelhas apresentaram de duas a cinco emergências de ondas foliculares durante os tratamentos [2 ondas: 4,29% (3/70); 3 ondas: 34,29% (24/70); 4 ondas: 52,86% (37/70); e 5 ondas: 8,57% (6/70) das ovelhas]. Não houve efeito do tratamento sobre os dias de emergência das ondas (Onda 1: 2,05±0,42 vs. 2,02±0,37; Onda 2: 5,69±0,42 vs. 5,65±0,37; Onda 3: 9,77±0,42 vs. 10,09±0,37; Onda 4: 11,85±0,39 vs. 12,12±0,35 e; Onda 5: 12,5±0,40 vs. 12,16±0,78 dias para G-1CIDR e G-2CIDR respectivamente; P>0,05). Similarmente, os períodos estacionais não interferiram sobre os dias de emergência para as ondas 1, 2, 3, 4 e 5, respectivamente (Anestro: 2,01±0,46, 5,11±0,47, 9,33±0,45, 12,27±0,40 e 13,50±0,40; Transição: 2,12±0,51, 5,95±0,52, 10,32±0,51, 11,16±0,78 e 11,61±0,50; e Ciclicidade: 1,99±0,42, 5,95±0,42, 10,14±0,42 e 12,08±0,43; P>0,05). Na estação de ciclicidade, nenhuma ovelha apresentou cinco ondas. No segundo experimento, foram utilizadas 60 novas fêmeas, sendo 20 para cada período... / Two experiments were conducted, in the first, 70 ewes were submitted to one of two synchronization protocols in three seasons (Factorial 2x3; Non-breeding: G-1CIDR, n=12 and G-2CIDR, n=11; Transition: G-1CIDR, n=12 and G-2CIDR, n=12; Breeding: G-1CIDR, n=11 and G-2CIDR, n=12). On D0 (randomized day of estrus cycle), the estrus were synchronized with a P4 device (CIDR) for 14 days. However, in G-2CIDR, the CIDR was replaced by a new one on D7. On D0 and D14, 2.5mg of a PGF2 analogue (dinoprost), i.m., were administered, and on D14, all ewes received 300 IU of eCG (Novormon™, Syntex- Argentina). Ultrasonographic exam was performed daily between D0 and D14 and, every 8 hours until D19. Data were analyzed by GLIMMIX using the SAS (P<0.05). Ewes presented two to five follicular waves emergencies during treatments [2 waves: 4.29% (3/70); 3 waves: 34.29% (24/70); 4 waves: 52.86% (37/70) and; 5 waves: 8.57% (6/70) of ewes]. There were no effect of treatment on emergency waves days (Wave 1: 2.05±0.42 vs. 2.02±0.37; Wave 2: 5.69±0.42 vs. 5.65±0.37; Wave 3: 9.77±0.42 vs. 10.09±0.37; Wave 4: 11.85±0.39 vs. 12.12±0.35 and; Wave 5: 12.5±0.40 vs. 12.16±0.78 days for G-1CIDR and G-2CIDR respectively; P>0.05). Similarly, there were no effect of seasons on these variables (Nonbreeding: 2.01±0.46, 5.11±0.47, 9.33±0.45, 12.27±0.40 and 13.50±0.40; Transition: 2.12±0.51, 5.95±0.52, 10.32±0.51, 11.61±0.50 and 11.16±0.78 and; Breeding: 1.99±0.42, 5.95±0.42, 10.14±0.42 and 12.08±0.43 days for waves 1, 2, 3, 4 and 5, respectively, P>0.05). In Breeding season no ewes showed five waves. In the second experiment, were used 60 new females, 20 for each season (breeding, transition and non-breeding) and 10 for each group that received one of two superovulatory protocols according to the time that FSH treatment were initiated (G-FirstWave and G-LastWave). Ewes were... (Complete abstract click electronic access below)

Orientador: Wilter Ricardo Russiano Vicente / Coorientador: Jeferson Ferreira da Fonseca / Coorientador: Sony Dimas Bicudo / Banca: Guilherme de Paula Nogueira / Banca: Claudio Alvarenga de Oliveira / Banca: Eunice Oba / Banca: César Roberto Esper / Resumo: Foram realizados dois experimentos, no primeiro, 70 ovelhas foram submetidas a um dos dois protocolos de sincronização do estro, em três períodos estacionais (Fatorial 2x3; Anestro: G-1CIDR, n=12 e G-2CIDR, n=11; Transição: G-1CIDR, n=12 e G-2CIDR, n=12; Ciclicidade: G-1CIDR, n=11 e G-2CIDR, n=12). O estro foi sincronizado com um dispositivo intravaginal de progesterona (P4; CIDR) por 14 dias. No G-2CIDR, o CIDR foi trocado por um novo no D7 (D0 = início do protocolo). No D0 e 14, 2,5 mg de um análogo da PGF2 (dinoprost) foram administradas, i.m., em todas as ovelhas. Exames ultrassonográficos dos ovários, por via transretal, foram realizados diariamente durante os protocolos (14 dias). Os dados foram analisados por regressão logística utilizando o Proc GLIMMIX do SAS (P<0,05). As ovelhas apresentaram de duas a cinco emergências de ondas foliculares durante os tratamentos [2 ondas: 4,29% (3/70); 3 ondas: 34,29% (24/70); 4 ondas: 52,86% (37/70); e 5 ondas: 8,57% (6/70) das ovelhas]. Não houve efeito do tratamento sobre os dias de emergência das ondas (Onda 1: 2,05±0,42 vs. 2,02±0,37; Onda 2: 5,69±0,42 vs. 5,65±0,37; Onda 3: 9,77±0,42 vs. 10,09±0,37; Onda 4: 11,85±0,39 vs. 12,12±0,35 e; Onda 5: 12,5±0,40 vs. 12,16±0,78 dias para G-1CIDR e G-2CIDR respectivamente; P>0,05). Similarmente, os períodos estacionais não interferiram sobre os dias de emergência para as ondas 1, 2, 3, 4 e 5, respectivamente (Anestro: 2,01±0,46, 5,11±0,47, 9,33±0,45, 12,27±0,40 e 13,50±0,40; Transição: 2,12±0,51, 5,95±0,52, 10,32±0,51, 11,16±0,78 e 11,61±0,50; e Ciclicidade: 1,99±0,42, 5,95±0,42, 10,14±0,42 e 12,08±0,43; P>0,05). Na estação de ciclicidade, nenhuma ovelha apresentou cinco ondas. No segundo experimento, foram utilizadas 60 novas fêmeas, sendo 20 para cada período... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Two experiments were conducted, in the first, 70 ewes were submitted to one of two synchronization protocols in three seasons (Factorial 2x3; Non-breeding: G-1CIDR, n=12 and G-2CIDR, n=11; Transition: G-1CIDR, n=12 and G-2CIDR, n=12; Breeding: G-1CIDR, n=11 and G-2CIDR, n=12). On D0 (randomized day of estrus cycle), the estrus were synchronized with a P4 device (CIDR) for 14 days. However, in G-2CIDR, the CIDR was replaced by a new one on D7. On D0 and D14, 2.5mg of a PGF2 analogue (dinoprost), i.m., were administered, and on D14, all ewes received 300 IU of eCG (Novormon™, Syntex- Argentina). Ultrasonographic exam was performed daily between D0 and D14 and, every 8 hours until D19. Data were analyzed by GLIMMIX using the SAS (P<0.05). Ewes presented two to five follicular waves emergencies during treatments [2 waves: 4.29% (3/70); 3 waves: 34.29% (24/70); 4 waves: 52.86% (37/70) and; 5 waves: 8.57% (6/70) of ewes]. There were no effect of treatment on emergency waves days (Wave 1: 2.05±0.42 vs. 2.02±0.37; Wave 2: 5.69±0.42 vs. 5.65±0.37; Wave 3: 9.77±0.42 vs. 10.09±0.37; Wave 4: 11.85±0.39 vs. 12.12±0.35 and; Wave 5: 12.5±0.40 vs. 12.16±0.78 days for G-1CIDR and G-2CIDR respectively; P>0.05). Similarly, there were no effect of seasons on these variables (Nonbreeding: 2.01±0.46, 5.11±0.47, 9.33±0.45, 12.27±0.40 and 13.50±0.40; Transition: 2.12±0.51, 5.95±0.52, 10.32±0.51, 11.61±0.50 and 11.16±0.78 and; Breeding: 1.99±0.42, 5.95±0.42, 10.14±0.42 and 12.08±0.43 days for waves 1, 2, 3, 4 and 5, respectively, P>0.05). In Breeding season no ewes showed five waves. In the second experiment, were used 60 new females, 20 for each season (breeding, transition and non-breeding) and 10 for each group that received one of two superovulatory protocols according to the time that FSH treatment were initiated (G-FirstWave and G-LastWave). Ewes were... (Complete abstract click electronic access below) / Doutor

The aim of the present study was to determine if there is a difference in ovulation- and conception rates, in semiintensively managed Dohne-Merino ewes, flush fed with diets containing different nitrogen sources. Four different nitrogen sources were chosen due to the difference in dietary amino acid composition and cost. In order for a sheep farming enterprise to maximize profitability it is essential to optimize ovulation- and conception rates and to minimize lamb losses in order to increase weaning percentage and therefore profitability. However the cost of dietary supplementation is high and may increase production costs and minimize profitability. One hundred and fourty four (144) Dohne-Merino ewes (age between 14 to 85 months) were included in two dietary supplementation trials (autumn and summer) at the experimental farm of the University of Pretoria in Hatfield. The ewes were divided equally into two trial groups (n=72), with the first trial done in season 1 (started in May 2001, typical breeding season) and the second trial done in season 2 (started in November 2001, out of season; 2nd breeding season). During the day the ewes had ad-libitum access to graze on Festuca arundinaceace (Tall Fescue). In both trials the ewes (n=72) were randomly allocated into four dietary supplementation groups, each group receiving a dietary supplement with a different combination of nitrogen sources. The four dietary supplements were formulated on an iso-nitrogen basis, to eliminate the effect of protein level, and to emphasize the possible effect of protein quality (amino acid composition) on ovulation, conception and lambing rates. In both trials the total amount of crude protein intake per ewe was calculated at 256.40g/day, while the total daily allowance of digestible crude protein was calculated at 190g per ewe. The 256.40g crude protein intake per ewe per day is 2 times more than the threshold level of 125g per ewe per day. A minimum daily crude protein intake of 125g is needed for effective rumen functioning, and this together with the interconvertin of energy by the rumen indicates the complex nature of relating dietary differences to physiological responses. These values were kept the same for both the trials in season 1 and 2. The bulk of the 256.40g crude protein per day was obtained from grazing on the Festuca arundinaceace pasture. In season 1 the dietary supplement had to provide 40.00g of crude protein per day in order to get to a daily crude protein intake of 256.40g, while in season 2 the provision from the dietary supplement was calculated to be 37.45g of crude protein. The difference in the crude protein level, obtained from grazing of the Festuca arundinaceace between season 1 and 2 was due to pasture quality differences. The nitrogen sources used in the trials were urea, sunflower oilcake meal, cottonseed oilcake meal and a mixture of cottonseed oilcake meal and fishmeal. These dietary supplements were fed for a period of 9 days before mating; the weight of each ewe was recorded before the onset of the trial and again on the second day after mating to establish any live weight changes. Synchronization of the ewes was done with Chrono-gest grey sponges (40mg Fluorogestone acetate) from day one and was repeated from day 23. On day 12 each ewe were injected with 1.0ml prostaglandin F2α (Prosolvin,each milliliter containing 7.5mg Luprostiol). On day fourteen the sponges were removed and two days later all the ewes were checked for cyclic activity with the aid of six vasectomized rams. The six vasectomized rams were introduced to the whole laparoscopy group of 12 ewes, and every ewe that stood twice for mating were identified as cyclic. This practice continued for a period of 30 minutes in the morning and repeated for another 30 minutes in the afternoon up to day 18. The second round of sponges were inserted on day 23 and removed on day 37. Ewes were mated by means of hand mating with two different rams from day 39 to 42. A laparoscopy technique was used on day 45 of the trial to count the number of ovulation points (corpora lutea) on each ovarium of each ewe. The number of fetuses of each ewe was counted on day 90 after mating by means of ultrasound scanning and at birth the number of lambs born was also recorded. In both these trials dietary supplementation had no significant effect on ovulation, conception and lambing rates. However, looking at the Odds Ratio Analysis for the 144 ewes over the two breeding seasons, the different dietary supplements had a significant influence on the number of ovulation points (p<0.05). Compared to urea (dietary supplement 1), the fishmeal cottonseed oil cake mixture (dietary supplement 4) yielded the best results (1.306), followed by the cottonseed oil cake meal (dietary supplement 3) (1.298), and sunflower oil cake meal (dietary supplement 2) (1.050). The same Odds Ratio Analysis showed that the different dietary supplements had a significant effect on the number of lambs born (p<0.01). Compared to urea (dietary supplement 1), the fishmeal cottonseed oil cake mixture (dietary supplement 4) yielded better results (1.086), followed by urea (dietary supplement 1) (1.000), and sunflower oil cake meal (dietary supplement 2) (0.801) and lastly cottonseed oil cake meal (dietary supplement 3) (0.784). Breeding season (p<0.05) had a significant effect on the number of ovulation points but no difference was observed in terms of the number of lambs born. Age (p<0.01) had a significant effect on the number of ovulation points, the number of fetuses counted as well as the number of lambs born. Change in live weight (p<0.05) had a significant effect on the number of ovulation points per ewe but as with breeding season it had no significant effect on the number of lambs born. Birth status of a ewe (p<0.05), had a significant effect on the number of fetuses and the number of lambs born. The data of both the trials in season 1 and 2 suggests that under the conditions of the study with the odds ratio analyses that the four different dietary supplements had a significantly different effect compared to dietary supplement one on the number of ovulation points and the number of lambs born. However, factors like breeding season, age, change in live weight and birth status of the ewe also had a significant effect on ovulation and conception rates in Dohne-Merino ewes. / Dissertation (MSc(Agric))--University of Pretoria, 2011. / Animal and Wildlife Sciences / unrestricted

Secretoneurin (SN) is a 31-42 amino acid neuropeptide, derived from the proteolytic processing of the precursor protein secretogranin-II (Scg2). In zebrafish, SNa and SNb are respectively 34 and 31 amino acids long, deriving from selective processing of the distinct Scg2a and Scg2b precursors. Our lab recently reported that frameshift mutations in Scg2 leads to reduces sexual behavior and disrupted spawning. This defect was partially rescued by injection of SNa. In my work, we determined the distribution of SNa in relation to other known reproductive hormones in zebrafish brain and pituitary by double immunofluorescent staining. SNa-immunoreactivity (ir) was observed in neuronal cell bodies in the ventral telencephalon, preoptic area (POA) and hypothalamus. Neuronal fibers staining for SNa projecting from the magnocellular POA passed through the pituitary stalk and terminated largely in the neurointermediate lobe (NIL). The SNa-ir fibers were less abundant but clearly present in the pars distalis. Moreover, SNa colocalized with isotocin in cell bodies in the POA and fibers in the NIL. Using the lhb-RFP x fshb-eGFP transgenic zebrafish line, we observed SNa-ir near gonadotroph cell bodies but not in them. Peptidomic analysis uncovered shorter processed fragments of both in SNa and SNb in whole brain and pituitary. We performed mass spectrometry to determine natural periovulatory variations and studied their potential bioactivities. Both SNa1-34 and SNa1-14 in the brain varied during the ovulatory cycle, while SNb-related peptides were relatively stable. The levels of SNa1-34 in brain peaked coincident with increased Gnrh3 at the time of the luteinizing hormone (Lh) surge. The levels of SNa1-14 in brain and ovaries peaked at the time of ovulation. To investigate the potential bioactivity of SNa1-34 and SNa1-14, we performed intraperitoneal injections and analyzed the expression numerous reproductive genes. The results suggested that SNa1-34 could induce ovulation by stimulating time-dependent expression of gnrh3 in brain, cga and lhb in pituitary and npr in ovaries. In contrast, SNa1-14 exhibited far fewer effects, but stimulated the expression of gnrh2 but suppressed gnrhr2, so its natural biological function remains unknown. After a single injection of SNa1-34 in females isolated from males, 61% (11/18) zebrafish ovulated. This compares favorably with the effects of the Lh analog human chorionic gonadotropin, inducing ovulation in 72% (13/18) of females. Natural variations in levels of SN in relation to other well-known neuropeptides and biological activity data in the zebrafish model support the hypothesis that SNa is a new stimulatory reproductive hormone. The SN peptides are conserved in evolution so what we uncover in fish may help us speculate on its importance in other vertebrates.

No description available.

No description available.

Dans le cadre de la production de nouvelles espèces aquacoles, le sandre, Sander lucioperca, est devenu, depuis plusieurs années, une espèce d’intérêt piscicole en raison de sa valeur économique potentielle. Pour développer et pérenniser sa production aquacole, il est nécessaire de comprendre et maîtriser son cycle de reproduction ainsi que les mécanismes physiologiques mis en jeu afin d’obtenir des œufs et des juvéniles viables tout au long de l’année. Dans cet optique d’optimisation du contrôle du cycle, la dopamine apparaît, chez de nombreux téléostéens dont certains perciformes, comme un inhibiteur de l’axe gonadotrope, via les récepteurs de la famille D2, en bloquant le pulse ovulatoire de LH et l’ovulation. Chez le sandre, le rôle de la dopamine et de ses récepteurs, notamment les récepteurs de la famille D1, est inconnu. L’objet de cette thèse est de déterminer le rôle du système dopaminergique lors des phases finales de l’ovogénèse chez le sandre à travers trois axes principaux : (1) déterminer l’effet du blocage des récepteurs de la dopamine, D1 ou D2, sur la régulation de l’axe gonadotrope et l’induction de l’ovulation en absence et en présence d’une molécule de sGnRHa, (2) définir le répertoire et le profil d’expression des récepteurs dopaminergiques par l’étude du transcriptome cérébral du sandre en période pré-ovulatoire et (3) établir le rôle de la dopamine et de ses différents récepteurs (familles D1 et D2) dans la régulation directe et locale de l’axe gonadotrope aux niveaux cérébral et ovarien. La première partie de ce travail a permis pour la première fois, par l’utilisation d’antagonistes spécifiques des familles de récepteurs D1 et D2, de mettre en évidence un rôle potentiel de la dopamine sur la sécrétion de certains stéroïdes sexuels en période pré-ovulatoire chez le sandre par l’intermédiaire des récepteurs de la famille D1. L’identification de l’ensemble des récepteurs de la dopamine existant chez le sandre nous a permis de confirmer leur expression à tous les niveaux de l’axe gonadotrope (cerveau, hypophyse et ovaires) étayant l’hypothèse d’un rôle de la dopamine dans la reproduction du sandre. Enfin, la dernière partie de ce projet a permis de montrer un rôle régulateur du système dopaminergique, directement au niveau ovarien, sur la production de testostérone par l’intermédiaire des deux familles de récepteurs de la dopamine. L’implication des deux familles de récepteurs a également été mise en évidence dans la production ovarienne de la 17β-estradiol. Au niveau cérébral, seule la famille des récepteurs D2 a été montrée impliquée dans la régulation de l’expression du gène de la GnRH-3. De façon générale, cette étude a permis de mettre en évidence l’implication des récepteurs de la dopamine dans la régulation de l’axe gonadotrope lors des phases finales de l’ovogenèse. Toutefois, des travaux ultérieurs devront être menés pour approfondir les mécanismes physiologiques mis en jeu. D’un point de vue aquacole, les traitements hormonaux à base d’antagonistes des récepteurs de la dopamine ont été inefficaces pour améliorer les performances de reproduction du sandre ce qui n’est pas en faveur de leur utilisation future pour induire l’ovulation chez cette espèce. Ainsi, la mise au point d’autres méthodes d’optimisation sera nécessaire pour continuer à développer la production aquacole du sandre / Pikeperch, Sander lucioperca, is a potential valuable economic fish, making it a species of interest for aquaculture diversification. In the domestication process, controlling and understanding the reproductive cycle is a crucial step in order to produce viable offspring in a synchronous and predictable way. In many teleosts including some perciforms, dopamine inhibits the ovulatory pulse of LH and the ovulation step through D2 dopamine receptors family. In pikeperch, the roles of dopamine and its receptors, especially those belonging to the D1 receptors family, are unknown. For the purpose of the optimization of pikeperch reproduction, we investigated the role of the dopaminergic system during the final stages of oogenesis in this species: (1) by determining the effects of D1 or D2 receptor antagonists alone or in association with sGnRHa on the regulation of the reproductive axis and on the induction of ovulation, (2) by determining the repertoire and the expression profile of the dopamine receptors using a brain transcriptome analysis during the pre-ovulatory period and (3) by evaluating the role of dopamine and its receptors (D1 and D2 families) in the direct and local regulation of the gonadotropic axis at the brain and ovarian levels. For the first time, we showed that the dopamine/D1 receptors complex regulates the sex-steroids release during the pre-ovulatory period, suggesting that dopamine is involved in pikeperch reproduction. Also, we support its involvement thanks to the identification of the dopamine receptors gene expression at the brain, pituitary and ovarian levels. Finally, we showed that the dopaminergic system directly regulates the ovarian testosterone production, through both D1 and D2 receptor families. The involvement of both dopamine receptor families was also highlighted on ovarian 17β-estradiol production. Only the D2 receptor family was shown to be involved on the brain GnRH-3 gene expression. In conclusion, we point out a dopamine receptors implication on the gonadotropic axis regulation during the final stages of oogenesis in pikeperch. However, further studies should be performed to pinpoint the physiological mechanisms behind this phenomenon. From an aquaculture point of view, hormonal treatments with dopamine receptor antagonists appear to be ineffective to improve pikeperch reproductive performances. Therefore, their use to induce pikeperch ovulation should be put into question and the development of alternative methods is necessary to further promote pikeperch production