O sucesso no emprego da inseminação artificial em suínos depende de inúmeros fatores, sendo o momento ideal de sua realização, um dos que mais influencia, o qual compreende um intervalo entre 0 e 24 horas antes da ovulação. Estudou-se as relações entre o intervalo desmame-cio (IDC), a duração do cio (DC) e o momento da ovulação (MO) e a influência da raça, ordem de parto e estação do ano sobre estas características e suas relações. Um total de 236 fêmeas, de uma unidade de produção de suínos no oeste Santa Catarina, foram observadas para a obtenção dos dados de IDC e DC, as quais eram testadas para o diagnóstico de cio 4 vezes ao dia, na presença do macho. A ovulação foi diagnosticada em 77 fêmeas, pela ultra-sonografia, por via trans-cutânea, em 3 exames diários com 8 horas de intervalo. As amostras de sangue para análise de progesterona, foram coletadas de 74 fêmeas, com 24 horas de intervalo, em 4 ocasiões para a determinação dos níveis: basal, 24, 48 e 72 horas após o início do cio, respectivamente, e submetidas a técnica de radioimunoensaio. A raça Landrace mostrou um IDC mais longo (113,62 horas) em comparação à Large White (linhagem 1) (102,45 horas) (P<0,05), mas não houveram diferenças significativas destas em relação à Large White (linhagem 2). Fêmeas de 1º parto apresentaram um IDC mais longo (117,44 horas) que às de 2º parto (100,47 horas) e acima deste (104,78 horas) (P<0,05). Não houve influência da estação do ano sobre nenhuma das características. Houve interação entre estação do ano e ordem de parto sobre o MO, sendo que, nas fêmeas acima de 2º parto, o MO médio estimado foi de 51,76 horas na estação 1 e de 36,56 horas na estação 2 (P<0,05). Houve correlação negativa entre intervalo desmame-cio e duração do cio (r=-0,4657; P=0,0001) e entre intervalo desmame-cio e momento da ovulação (r=-0,3955; P=0,0004), no entanto, não houve correlação entre duração do cio e momento da ovulação (r=0,2201; P=0,0578). Não foi possível mostrar influências de raça, ordem de parto e estação de ano sobre as relações entre IDC, DC e MO através da análise de regressão com comparação de retas. Houve baixa correlação entre a ultra-sonografia e a análise de progesterona (MOP), para o diagnóstico da ovulação (r=0,3396;P=0.0209), sem correlação quando a ocorrência da ovulação foi considerada em intervalos de 24 horas a partir do início do cio (r=0,2637;P=0,0766). A porcentagem de fêmeas que, pela ultra-sonografia, ovularam entre 0 e 24, 24 e 48, 48 e 72 e acima de 72 horas após o início do cio foi de, respectivamente, 0%, 58,4%, 37,5% e 4,2% para o IDC de 3 dias, 3,2%, 67,7%, 29,2% e 0% para o IDC de 4 dias, 0%, 91,6%, 8,3% e 0% para o IDC de 5 dias e 10%, 90%, 0% e 0% para o IDC de 6 e 7 dias. Pela análise de progesterona, para os mesmos intervalos, respectivamente, a porcentagem fêmeas foi de 4,5%, 36,3%, 50% e 9,1% para o IDC de 3 dias, 3,6%, 32,2%, 60,7% e 3,6% para o IDC de 4 dias, 5,9%, 35,3%, 52,9% e 5,9% para o IDC de 5 dias e 14,3%, 57,1%, 28,6% e 0% para o IDC de 6 e 7 dias. Nestas condições, o I DC não se mostrou uma referência confiável para ser utilizado como um preditor do momento ideal da inseminação. No entanto, conhecimento das características IDC, DC e MO dentro de cada rebanho ajudam a apontar falhas e elaborar programas eficientes de IA. / The success of artificial insemination (AI) depends on several factors. The ideal moment to realize the AI is a limiting factor and it is defined as O to 24 hours before ovulation. Relationships between weaning-to-estrus interval (WEI), duration of estrus (DE) and moment of ovulation (MO) and the influence of breed, parity and season over these characteristics and the relationships with each other were studied. In a total of 236 sows, of a farm in the west of Santa Catarina, were observed to record the data of WEI and DE, which were tested by back pressure 4 times a day, in presence of a boar. The ovulation was diagnosed in 77 sows, by transcutaneous ultrasonography, 3 times a day at intervals of 8 hours. The blood samples to progesterone analyze were collected of 74 SOWS, at 24 hours intervals, at 4 occasions to determine basal, 24, 48, 72 hours levels after estrus onset, respectively, and submitted to radioimunoassay. The breed Landrace showed a WEI longer (113,62 hours) than Large White (Iine 1) (102,45 hours) (P<0,05), but there were no differences in relation to Large White (Iine 2). First parity sows presented a WEI longer (117,44 hours) than second parity sows (100,47 hours) and over second parity (104,78 hours) (P<O,05). There was no influence of season over ali the studied characteristics. There was interaction between season and parity over MO because females over second parity showed an average MO of 51,76 hours in season 1 and 36,56 hours in season 2 (P<0,05). There was negative correlation between WEI and DE (r=-O,4657; P=O,0001) and between WEI and MO (r=-O, 3955; P=O,0004), however, there was no correlation between DE and MO (r=0,2201; P=0,0578). It was not possible to show influence of breed, parity and season over the relationships between WEI, DE and MO by analyze of regression with line comparison. There was low correlation between ultrasonography and analyze of progesterone (MOP), to diagnose ovulation (r=O,3396;P=0.0209) and no correlation when the occurrence of ovulation was considered at intervals of 24 hours since onset of estrus (r=O,2637;P=O,0766). The percentage of females that ovulated (detected by ultrasonography), between O to 24, 24 to 48,48 to 72 and over 72 hours after the onset of estrus was, respectively, 0%, 58,4%, 37,5% and 4,2% to WEI of 3 days, 3,2%, 67,7%, 29,2% and 0% to WEI of 4 days, 0%, 91,6%, 8,3% e 0% to WEI of 5 days and 10%, 90%, 0% and 0% to WEI of 6 and 7 days. By progesterone levels, for the same intervals, respectively, the percentage was 4,5%, 36,3%, 50% and 9,1% to WEI of 3 days, 3,6%, 32,2%, 60,7% and 3,6% to WEI of 4 days, 5,9%, 35,3%, 52,9% and 5,9% to WEI of 5 days and 14,3%, 57,1%, 28,6% and 0% to IDe of 6 and 7 days. In these conditions, the WEI was not a good reference to be utilized as a predictor of ideal moment of insemination. However, the information about the characteristics WEI, DE and MO within each herd help to point the mistakes and to develop AI programs.

Antral ovarian folliculogenesis involves recruitment of a cohort of small follicles, physiological selection of a dominant follicle, and ovulation. The mechanism of selection has not been precisely determined. Identification of the timing of preovulatory selection is a key component in understanding natural and peri-menopausal ovarian function, ovarian suppression for contraception, and improvement of ovarian stimulation protocols. Morphologic characteristics obtained by ultrasonography cannot be precisely quantitated by the human eye. Computer-assisted image analysis overcomes subjective human evaluation of ultrasonographic images.<p> The objectives of this research were to assess ultrasound image attributes of human dominant (DF) and 1st subordinate (SF1) ovarian follicles during natural menstrual cycles and following discontinuation of conventional and continuous oral contraceptives (OC). We utilized sophisticated computer algorithms to elucidate an association between image attributes and physiologic status of follicles. Transvaginal ultrasonographic images obtained in 2 previous studies were used to quantify changes that occur in ovarian follicles.<p> We detected quantitative differences between the dominant and largest subordinate follicles of ovulatory and major anovulatory follicular waves, as well as during the first wave following OC discontinuation. Differences in ultrasonographic image attributes were associated with the physiological status of follicles. Evidence of follicular dominance in follicles which develop during major ovulatory waves or following OC discontinuation can be detected prior to the time of selection manifest by differences in dominant and subordinate follicle diameters. In addition, differences in quantitative image attributes were detected between ovulatory and anovulatory DF. Follicles that develop following conventional and continuous OC administration schemes exhibit the same image characteristics.<p> Further research is necessary to elucidate the exact correlation of follicle image attributes during all stages of development with histological characteristics, prediction of the timing of DF selection and the effects of different OC formulations on follicle development during and following OC cessation. Computer-assisted image analysis of ultrasound images has the potential to develop into a diagnostic, prognostic, and research tool for the in vivo evaluation of ovarian physiology and pathology and elucidate biologically important times such as physiologic selection, ovulation of DF and characterization of abnormal follicles (i.e., follicular cysts, luteinized unovulated follicles).

Antral ovarian folliculogenesis involves recruitment of a cohort of small follicles, physiological selection of a dominant follicle, and ovulation. The mechanism of selection has not been precisely determined. Identification of the timing of preovulatory selection is a key component in understanding natural and peri-menopausal ovarian function, ovarian suppression for contraception, and improvement of ovarian stimulation protocols. Morphologic characteristics obtained by ultrasonography cannot be precisely quantitated by the human eye. Computer-assisted image analysis overcomes subjective human evaluation of ultrasonographic images.<p> The objectives of this research were to assess ultrasound image attributes of human dominant (DF) and 1st subordinate (SF1) ovarian follicles during natural menstrual cycles and following discontinuation of conventional and continuous oral contraceptives (OC). We utilized sophisticated computer algorithms to elucidate an association between image attributes and physiologic status of follicles. Transvaginal ultrasonographic images obtained in 2 previous studies were used to quantify changes that occur in ovarian follicles.<p> We detected quantitative differences between the dominant and largest subordinate follicles of ovulatory and major anovulatory follicular waves, as well as during the first wave following OC discontinuation. Differences in ultrasonographic image attributes were associated with the physiological status of follicles. Evidence of follicular dominance in follicles which develop during major ovulatory waves or following OC discontinuation can be detected prior to the time of selection manifest by differences in dominant and subordinate follicle diameters. In addition, differences in quantitative image attributes were detected between ovulatory and anovulatory DF. Follicles that develop following conventional and continuous OC administration schemes exhibit the same image characteristics.<p> Further research is necessary to elucidate the exact correlation of follicle image attributes during all stages of development with histological characteristics, prediction of the timing of DF selection and the effects of different OC formulations on follicle development during and following OC cessation. Computer-assisted image analysis of ultrasound images has the potential to develop into a diagnostic, prognostic, and research tool for the in vivo evaluation of ovarian physiology and pathology and elucidate biologically important times such as physiologic selection, ovulation of DF and characterization of abnormal follicles (i.e., follicular cysts, luteinized unovulated follicles).

No description available.

Thesis (M.App.Sc. in Physiotherapy)--University of South Australia, 1997.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 114-119). Also available on the World Wide Web.

Diss. Linköping : Linköpings universitet, 2004.

Thesis (doctoral)--Lund University, 1997. / Added t.p. with thesis statement inserted.

Thesis (M.D.)--University of Hong Kong, 1995. / Includes bibliographical references (leaf 208-230).

Thesis (MHSc)--Unitec New Zealand, 2008. / Coda (electronic version) title-page has 2009 date. Includes bibliographical references (leaves 162-173).