Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 7, 2007) Includes bibliographical references.

The objective was to determine the effects of immunocastration (Improvest) on reproductive characteristics in boars. Seventy-two boars were used in a randomized design with three treatments: single injection (SI) or double injection (DI) of Improvest, and intact controls (no Improvest; CNT) (n = 24/group). At wk 10, 15, 20, 25, and 40, blood was collected and serum harvested to evaluate testosterone concentrations via RIA. At wk 25, 18 pigs (n = 6/ group) were sacrificed and testes were removed, weighed, and measured. Libido was assessed at 32, 36, 47, 60, and 63+ wk of age (1 to 5; 1 = no libido; 5 = high libido) and semen collected beyond 60 wk of age. Testosterone concentrations were less for DI boars compared to CNT boars and SI boars at 20 and 25 wk of age (P < 0.001), but not different at 40 wk of age. All testicular measurements and weight were less for DI boars compared to SI and CNT boars (P < 0.001). There was no treatment effect on libido between 32 to 63+ wk of age. Semen volume, gel weight and total number of sperm cells were not different among treatments. Sperm concentration was greater for DI than SI (P = 0.011), and tended to be greater for DI compared to CNT (P = 0.102). Sperm motility tended to be greater for DI boars compared to CNT boars (P = 0.066). The results show that there are no permanent effects of immunocastration on reproductive characteristics in boars. / Master of Science

L'objectiu principal d'aquesta tesi és contribuir a un millor coneixement dels mecanismes moleculars implicats en el correcte assoliment de la capacitació "in vitro" (IVC) i posterior reacció acrosòmica "in vitro" (IVAR) dels espermatozoides porcins. Amb aquesta finalitat es va estudiar, per una banda, l'evolució temporal de l'estructura subpoblacional en els espermatozoides porcins durant aquests processos i es va observar canvis espeífics en el percentatge de les diferents subpoblacions mòbils sense que es perdés l'estructura de 4 subpoblacions descrita en l'ejaculat porcí. Per altra banda, la IVC i la IVAR indueixen no sols canvis en la fosforil·lació dels residus tirosina de les proteïnes sinó que s'ha demostrat que la fosforil·lació en els residus serina i treonina també està relacionada amb la IVC i IVAR. Així, s'ha descrit, no tan sols l'aparició de fosforil·lació específica en determinades proteïnes, sinò també la inducció de canvis conformacionals en altres proteïnes i l'aparició de senyal de fosforil·lació en serina i treonina en l'acrosoma de l'espermatozoide relacionada amb IVC i IVAR. En tercer lloc, s'observà un augment de l'activitat mitocondrial durant la IVC i els primers minuts de IVAR. Nogensmenys, en aquest treball es descriu un patró concret d'activació mitocondrial, des de nuclis concrets situats majoritàriament a la part més perifèrica de la peça intermitja de l'espermatozoide cap a la part central d'aquesta. Tanmateix l'actina i la mitofusina2 són dos proteïnes que podrien jugar un paper important en la modulació de la funció mitocondrial en l'espermatozoide porcí. / The first and principal aim of this thesis is to improve our knowledgement in molecular mechanisms and control of "in vitro" capacitation (IVC) and further acrosome reaction (IVAR) in boar spermatozoa. We have studied the structural motile subpopulation, the protein phosphorylation in concrete in tyrosine, serine and threonine residues and finally the mitochondrial activity during IVC and IVAR.Our results suggest that capacitation-induced motility changes are related to specific changes in the percentage of each motile-sperm subpopulation in the ejaculate without losing the overall, specific four-subpopulation structure. In this way, the maintenance of a four-subpopulation structure seems to be important in the control of the whole ejaculate physiology.Moreover, this study indicates that the changes in protein phosphorylation associated with IVC and subsequent IVAR affected not only pTyr, but also pSer and pThre, and they comprise not only the appearance of specific phosphorylated proteins, like pTyr 32-kDa, pSer-75 kDa and pSer 80-kDa proteins, but also structural changes that induce changes in pI and displacements in the sperm location of the phosphorylated proteins, such as the appearence of specific IVC- and IVAR-linked pSer and pThre signals in the acrosome. Finally, it have been shown that the increase of boar sperm mitochondria activity during IVC and the first minutes of IVAR is instrumental to perform the sperm function changes associated with these processes. Furthermore, the increase in mitochondria activity is originated in concrete nucleation points at the midpiece. Finally, actin and mitofusin-2 play important roles in the modulation of boar sperm mitochondria function, both by originating changes in the protein membrane environment and by changes in the mitochondrial structure by itself.

The objectives of this study were to assess growth and reproductive performance of boars fed a diet supplemented with organic selenium (Se). Crossbred boars received one of three treatments: I. basal diet with no supplemental Se, II. basal diet supplemented with 0.3 ppm organic Se (Sel-Plex), and, III. basal diet supplemented with 0.3 ppm sodium selenite. Nursery (n = 13 pens/treatment) boar performance was not affected (P > 0.1) by diet and only grow-finish (n = 11 pens/treatment) G:F was greater (P < 0.06) for Sel-Plex (0.378) compared with selenite (0.368) or control (0.363) boars. At 15-mo of age semen was collected from boars (n = 10/treatment) over 5-d. Semen quality declined over time, but the negative impact day had on sperm motility was less pronounced with Sel-Plex boars. Effects of treatment x day were detected for progressively motile (P = 0.02) and rapidly moving (P = 0.03) spermatozoa, sperm path velocity (VAP; P = 0.05), and average velocity (VSL; P = 0.05). At 17-mo of age, semen was collected from boars (n = 10/treatment), extended and stored over 10-d. Although semen quality decreased over time, sperm from Sel-Plex boars resisted the negative effects of day on sperm motility and pH. Effects of treatment x day were detected for percent motile spermatozoa (P < 0.01), static spermatozoa (P < 0.01), VAP (P = 0.06), amplitude of head displacement (ALH; P = 0.02), straightness (P = 0.01), and pH (P < 0.01). At 23-mo of age, semen was collected (day 0) from boars (n = 6/treatment), extended, stored and evaluated at d 1 and 8 using in vitro fertilization. Dietary Se treatment failed to affect (P < 0.05) in vitro fertilizing rates of boars. In summary, dietary supplementation with Sel-Plex enhanced G:F in grow/finish boars. Dietary Sel-Plex supplementation may decrease the effects that stressors, such as intensive semen collection or semen storage, have on boar sperm characteristics such as sperm motility. The mechanisms for these responses remain to be elucidated. / Ph. D.

No description available.

Os objetivos do estudo foram: (a) relatar os procedimentos no condicionamento dos machos reprodutores no período pré-pubere de criação, averiguando o percentual de montas com sucesso, volume do ejaculado e concentração espermática. (b) Avaliar o efeito da suplementação de vitamina A em machos reprodutores nos parâmetros: volume, motilidade, concentração espermática e alterações morfológicas. A pesquisa foi desenvolvida no Laboratório de Pesquisa em Suínos, da FMVZ-USP, utilizando-se de animais de linhagens híbridas sintéticas, provenientes de uma granja reprodutiva localizada no sudoeste de São Paulo, local este, onde foi realizada a seleção dos animais a partir de 70 dias de idade e com peso médio de 25,16 Kg. Aos 117 dias de idade foi realizada a inspeção dos aprumos, testículos, bolsa prepucial e pênis, sendo selecionados 12 animais, que foram transferidos para o referido laboratório, aos 193 dias de idade, com peso médio de 147,00 Kg. O condicionamento iniciou-se aos 210 dias de idade dos animais, e, após 8 semanas, todos os reprodutores já estavam saltando no manequim, havendo a estabilização das colheitas. A partir deste período os valores das características, volume e concentração tornaram-se estáveis, demonstrando-se a homogeneidade dos animais que serviram para a fase experimental subsequente, relativa à avalição dos efeitos da vitamina A em animais submetidos a suplementação de vitamina A e controle. Nesta segunda fase experimental, foram verificadas diferenças significativas (p< 0,05) quanto à motilidade, concentração espermática quantificada pela câmara de Neubauer e alterações morfológicas, não havendo significância quanto à concentração total e volume do ejaculado. Houve significância (p< 0,05) quanto ao tempo nas 25 colheitas, semanais, quanto a concentração, quantificada na câmara de Neubauer e total, não se evidenciando interação x tratamento. Inferiu-se com o estudo que, dada à condição metabólica diferencial dos animais de genéticas híbridas sintéticas, novas averiguações devem ser direcionada para a relação nutrição x reprodução, devem ser averiguadas, uma vez que, os efeitos positivos da suplementação da vitamina A na espermatogênese foram destacados, principalmente nas características que mais se relacionam com a formação da célula espermática / The objectives of the study were: (a) Report the procedures for the conditioning of boars in the pre pubescent period of the breeding, by checking the percentage of succeed mounts, semen\'s concentration and volume. (b) Evaluate the effect of the vitamin A supplementation in boars, related to the parameters: volume, motility, semen concentration and changes in the morphology of the spermatozoids. The research was developed in the Swine Research Laboratory from the FMVZ, University of São Paulo, Pirassununga campus. In the first phase of the trial, which corresponded to the conditioning of the boars to the semen\'s collection process, 12 boars were utilized. The boars for the experiment came from a breeding swine operation located at the southeast of the SP state and were born from a hybrid synthetic genetic line. They were 70 days old and weighted an average of 25.16 Kg. At 117 days of age the inspection of the legs, testicles, prepuce\'s bag and penis was done. 12 animals among the 24 were selected and, at 193 days of age and weighting an average of 147 kg, they were transferred to the boars\' unit of the referred Laboratory. The conditioning process started at 210 days of age and 8 weeks after all the boars were already mounting on the dummy, which completed the phase of the collections\' stabilization. From this period, the values of the characteristics (volume and concentration) become stable, showing the homogeneity of the animals, which were used in the next experimental phase, related to the evaluation of the vitamin A effects on both treatments (Control and Vitamin A supplementation). In this second experimental phase we found significant differences (p< 0.05) considering motility, semen concentration determined by the Neubauer chamber and changes in the morphology of the spermatozoids, while no significant differences were found considering semen\'s concentration and volume. There was significance (P<0.05) considering time in the 25 collections, weekly collections, concentrations, Neubauer chambers and the total, while the interaction time x movement was not significant. The study lead us to conclude that due to the differential condition of the animals which were born from the present hybrid genetics, it is necessary to study the relationship nutrition x reproduction, once the positive effects of the vitamin A supplementation in the semen production was emphasized, mostly in the characteristics that are related to the formation of the sperm cells.

Os objetivos do estudo foram: (a) avaliar a influência da suplementação de vitamina A na dieta de cachaços nos parâmetros seminais: volume, motilidade, vigor espermático, pH, concentração espermática, número total de espermatozóides, percentual de espermatozóides vivos e anormalidades morfológicas ao longo do ano; (b) averiguar a variabilidade das características, em animais suplementados com vitamina A na dieta, frente às variações da temperatura nas estações do ano. A pesquisa foi desenvolvida no Laboratório de Pesquisa em Suínos, da FMVZ-USP, utilizando-se 10 machos de linhagem híbrida e distribuídos em dois tratamentos, controle (nível de 25.000 UI de vitamina A/animal/dia) e suplementado com a vitamina A (nível de 40.000 UI de vitamina A/animal/dia). O delineamento foi inteiramente casualizado, com medidas repetidas no tempo, sendo os dados analisados utilizando o programa estatístico Statistical Analysis System (SAS). As probabilidades de interações com o tempo foram determinadas pelo teste de Greenhouse-Geisser Epsilon, considerando o nível de significância de 5%. Em relação aos efeitos da vitamina A durante o período de 1 ano, verificou-se que não houve diferença entre os tratamentos para os parâmetros seminais, não encontrando-se efeito de interação tempo e tratamento. Detectou-se efeito de tempo para os parâmetros pH, concentração espermática, número total de espermatozóides, percentual de espermatozóides vivos e anormalidades morfológicas. Já na averiguação da variabilidade também não foi constatado efeito de tratamento, porém houve efeito de estação do ano para todos os parâmetros e de temperatura para o percentual de espermatozóides vivos, pH e anormalidades morfológicas, não sendo verificado efeito para os demais parâmetros. Inferiuse com o estudo que, dada à condição metabólica diferencial dos animais híbridas, novas averiguações devem ser perseguidas para a relação nutrição e reprodução, uma vez que, os efeitos positivos da suplementação da vitamina A na espermatogênese foram evidenciados, principalmente nas características que mais se relacionam com a formação da célula espermática, as anormalidades morfológicas, percentual de espermatozóides vivos e número total de espermatozóides no ejaculado. / The objectives of the study were: (a) to evaluate the effect of vitamin A supplementation on boars? diet considering the parameters: volume, motility, spermatic vigor, seminal pH, spermatic concentration, total number of spermatozoa, percentage of living sperm cells and morphologic abnormalities during one year; (b) to investigate the variability founded against the temperature and seasons of the year on vitamin A supplemented animals seminal parameters. The research was developed in the Laboratory of Research in Swines, the FMVZUSP, using 10 boars of hybrid lineages. Two treatments were used having the control (level of 25.000 UI of vitamin A/animal/day) and vitamin A supplemented group (level of 40.000 UI of vitamin A/animal/day). The statistical design was random, with repeated measured in time. The analyzed data used was the statistical program Statistical Analysis System (SAS). The probabilities of the interactions in time were determined by Greenhouse-Geisser Epsilon test, considering the significant level 5%. None of the evaluated parameters was significantly different and no detected interaction in time was found treatment. In relation to the effects of the vitamin A on supplementation in one year period it wasn?t have differences among treatments on seminal parameters, and also there wasn?t interaction in time and at treatment, however for pH, spermatic concentration, total number of spermatozoa, percentage of living sperm cells and morphologic abnormalities it was detected effect on time. In relation to the variability there wasn?t treatment effect, however there was for all the parameters studied effect of the season. The effect of temperature was only for the percentage of living sperm cells, pH and morphologic abnormalities. It was concluded that at a given metabolic condition of the hybrid animals, new ascertainments must be inquired for the relation nutrition and reproduction, a time that, the positive effect of the suplementation of the vitamin in spermatogenesis had been evidenced, mainly in the characteristics that more become related with the formation of the espermática cell.

Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 101-107). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 101-107). Also available on the Internet.

The new legislative situation raises once again the question which alternatives exist in order to avoid boar taint exist, if piglet castration would be forbidden and fattening of boars would be a common practise. The aim this study was to contrast approaches from the large number of new and elder literatures with the subjects of reducing and eliminating boar taint and to assess the effectiveness of these methods to avoid boar taint. For the first time, these findings were presented in a summarised and concentrated form. After reviewing 857 titles out of the year 1911 up to 2015, 664 sources of literature were chosen from all fields of pig breeding, housing and feeding, application of drugs, meat processing and the answer of consumers give a comprehensive understanding on the term of boar taint and the alternatives of piglet castration. There is no single strategy against boar taint being exposed after this work. There are some approaches possible: the immunocastration that gained acceptance in Australia and Belgium is an animal welfare friendly and in practice feasibly method. But it needs an inspection for boar taint at the slaughter line. The fattening of young boars, supported by Switzerland, could be improved by an optimised housing and feeding strategy, as well as the use of breeding lines for low boar taint. The processing of boar meat to premium products is possible. However, the amount of tainted boar meat coming into processing is still not clarified. It remains to be seen, how Germany will solve the problem of piglet castration.