No description available.

No

Thesis (Ph. D.)--University of Chicago, Commitee on the History of Culture, June 2002. / Includes bibliographical references. Also available on the Internet.

Abstract This study investigated the optimal operating parameters on road dust removal by a flusher. It aimed at enhancing road flushing efficiency, analyzing particle size range, and establishing a flushing model. This study explored main roads by collecting road dusts in Kaohsiung metropolitan area in October 2001. The roads were classified by road dust loading (RDL) as follows: level A (minor, RDL<1g/m2), level B (normal, RDL=1~5g/m2), level C (abnormal, RDL=5~11g/m2), and level D (serious, RDL= 11~25g/m2). The frequency of road flushing was recommended as follows: Level D roads were flushed every day to maintain RDL≤20g/m2. Level C roads were flushed every day, while level B roads were flushed every two days, to keep RDL≤10g/m2. Level A roads were flushed every week to maintain RDL≤5g/m2. A pilot-scale road-flush testing field was designed for this particular study to investigate the influence of operating parameters on road flushing efficiency. The findings indicated that flat-fan type nozzle demonstrated higher flushing efficiency than hollow-cone type nozzle, and that the flushing speed and the distance of the nozzle away from the ground were correlated negatively with the road flushing efficiency, whereas the pressure of nozzle and RDL was correlated with the road flushing efficiency. The results suggested that, in the condition of eighty percent of flushing efficiency, the optimal operating parameters were flushing speed of 15km/hr, the pressure of nozzle of 2.0kg/cm2, the distance away from the ground of 30cm, the angle of 40o, and the particle size less than 150£gm. The results showed that particle size was correlated negatively with the road flushing efficiency under various operating parameters of flushing for different road levels. Beside, the road flushing efficiency was above 80% for silt with particle size less than 75£gm. However, for particle size larger than 850£gm, the road flushing efficiency was up to 40%. It concluded that the road flushing efficiency of fine particles was better than that of coarse particles. After conducting dimensionless analysis and multiple regression analysis, the model of road flushing efficiency can be shown as follows, ¡]R¡×0.8276¡^ where £b is the road flushing efficiency, U is the flusher speed (m/s), P is the water injecting pressure (N/m2), W is the road dust loading (kg/cm2), H is the distance of nozzle away from the ground (m), q is the amount of water per square meter (m3/m2), and £c is the angle of nozzle spread. In this model, RDL is negatively correlated with U, W and H. Moreover, the road flushing efficiency increases with water injection pressure and flow rate. On the basis of the above model, the average percentage of error was approximately 0.28%. In this study, the optimal operating parameters of a flusher were that the flushing speed of 10km/hr, water injecting pressure of 2.0kg/cm2, the distance of nozzle away from the ground of 20cm, and the water injecting angle of 45o. However, depending upon the road cleanness levels, the optimal operating parameters could be varied. For instance, the distance of the nozzle away from the ground should be increased up to 30cm in order to prevent the damage from uneven roads or cavities. The experiments showed that 30cm of the height was a better option due to the road flushing efficiency was only 2% lower while compared with that of 20cm. After the analysis of experimental data, the results can serve as the operation condition for road flushing practice as authorities concerned. The operating parameters proposed in this study could be useful for basic design of a high-efficiency flusher. Moreover, the model of road flushing efficiency can be further applied to predict the road flushing efficiency.

No description available.

Reservoir sediment flushing is increasingly considered beneficial to reduce sedimentation of reservoirs and maintain sediment supply downstream of impounded rivers. Nevertheless, flushing of the accumulated sediments downstream of the dam also bears numerous negative impacts. In this study, first the most important downstream impacts of fine sediment releases of flushing were identified based on previously published research of twenty case studies in eleven countries. The results showed that the long-term as well as short term biological and physical impacts decreased with distance from the dam. The temporal scale of impacts on macro-invertebrates could span from few weeks or a month to several months while the effect on fish could last for a number of years. The impacts on downstream vegetation dynamics is driven by many years of flushing activities. The study also enabled proposing generic management strategies aimed to reduce the impacts. Second, fine sediment transport in coarse immobile bed, which is a common phenomenon downstream of dams during flushing releases, dam removal and also in many mountain and canyon rivers, was investigated. Particularly, the dynamics of the downstream erosion and transport of fine sediments released during sediment flushing was investigated based on a series of flume experiments that were carried out in immobile gravel bed and using a one-dimensional (1-D) suspended sediment transport model developed in the present study. In the framework of the flume experiment, firstly gravel bed roughness, porosity and roughness density were exclusively extracted from gravel surface elevation data in which developing a spatial filter to overcome elevation errors was carried out. Secondly a new technique to acquire fine sediment erosion in immobile coarse bed in running water condition was developed. The method proved to be the back bone of all fine sediment erosion experiments conducted in the present study and could be used for similar studies. This study presents a first work of direct measurement of erosion rate and characterizing its spatial heterogeneity in gravel bed. The experimental data of erosion rate of fine sediments showed that it varied spatially with high erosion rate on the stoss side of gravels and less on the lee side conforming to sweeps and ejections characteristics in coherent flow structure of gravel bed flows. Erosion rate was significantly affected by increase in roughness of immobile gravel bed with high erosion rate noticed when sand level was reduced although the effect on stream-wise velocity was not significant. The vertical profile of erosion rate was found to decrease linearly and showed an exponential decay in time in the gravel matrix. Third, a new non-equilibrium erosion rate relation is proposed. Drag force profile in the interfacial sublayer of clean gravel bed was found to be scaled well with roughness density and allowed predicting the effective shear stress distribution available for fine sediment entrainment with an empirical equation. vi The new relation is a modified version of the pick-up rate function of van Rijn (1984b) in which the predicted shear stress in the roughness layer was implemented. The most important finding was that if the shear stress distribution in the interfacial sublayer is predicted, a relation for sand bed condition can be applied to predict fine sediment erosion rate in immobile gravel bed. This approach is conceptually superior to previous approaches where erosion rate in sand bed condition was scaled empirically for various fine sediment bed level within the interfacial sublayer. Finally, the effect of the interaction between hydrodynamic and sediment wave dynamics of sediment flushing on spatial pattern of sediment deposition was investigated. The 1-D model was developed to include major processes observed in sediment flushing: sediment wave celerity correction, variable bed roughness, bed exchange in immobile bed, hindered settling velocity and rough bed porosity. The proposed erosion rate relation showed encouraging results when implemented in the 1-D model. The wave celerity factor did not show significant effect on the spatial lag in immobile bed condition although was significant in sand bed condition. Variable bed roughness modified both the flow field and sediment deposition in which larger length of sediment deposit was noted. The immobile bed porosity allowed modelling clogged depth of fine sediments. The model was also found to be very valuable to investigate flushing scenarios that reduce significant deposition through the analysis of the dependence of deposition on peak-to-base flow and intermittence of releases. The highest peak-to-base flows produced the longest and thickest region of deposition while those with the lowest ratio produced the shortest and thinnest. A single flushing release followed by clear water release reduced area or length of sediment deposition more than intermittent flushing followed by inter- and post-flushing clear water releases. In the latter case, the peak of concentration reduced but remained higher for longer duration than the former, which suggests that a large quantity of clear water release has to be available. Overall, the present research represents a step forward in understanding relevant processes involved in the downstream transport of fine sediments released during sediment flushing and the associated impacts that can help the development of better management strategies and predictive tools.

O objetivo do estudo realizado no Laboratório de Pesquisa em Suínos, da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, Pirassununga – SP, foi verificar os efeitos combinados de gonadotrofinas exógenas, (eCG e LH) e flushing sobre a duração e dispersão da manifestação do primeiro e segundo estros, ciclicidade das fêmeas, número de ovulações, viabilidade embrionária e freqüência de cistos ovarianos. Foram utilizadas 72 marrãs pré-púberes da linhagem Pen Ar Lan NAIMA®, com idade média de 157,49±5,01 dias, e 96,65±7,70kgs de peso, distribuidas em quatro tratamentos, em arranjo fatorial, com e sem flushing , e com e sem hormônio. A ração utilizada continha 16% de PB e 3.286,73 kcal/kg ME. A partir do 7º dia do primeiro estro, induzido com hormônio, as fêmeas do tratamento com flushing receberam 50% de incremento da mesma ração. No 16º dia, após o primeiro estro, as marrãs no tratamento hormonal receberam aplicação de 600 UI de eCG (Novormon®) e 2,5 mg de LH (Lutropin®), 72 horas após. Todas as marrãs foram expostas ao macho duas vezes ao dia, a partir do 10º dia e inseminadas ao segundo estro com sêmem heterospérmico contendo 4 x 109 espermatozóides. Ao abate, realizado no 5º dia após a inseminação, os genitais foram colhidos para exame dos ovários e coleta dos embriões. Não se observou interação entre os fatores. Os efeitos analisados em separado, não evidenciaram diferença significativa no Número de ovulações (14,28±5,06 vs 13,47±5,57 com e sem Flushing e 14,60±5,78 vs 13,23±4,83 com e sem Hormônio, respectivamente, P>0,05), na freqüência de cistos ovarianos (22,86% vs 11,11%, com e sem Flushing e 15,15% vs 18,42%, com e sem Hormônio, respectivamente,. P>0,05), na Manifestação do 2º estro (85,71% vs 91,43% com e sem Flushing e 90,63% vs 86,84% com e sem Hormônio, respectivamente, P>0,05), no Peso Final (115,35±8,23 vs 111,56±8,30kg, com e sem Hormônio, respectivamente, P>0,05), na Espessura de toucinho (10,0±2,0 vs 10,2±1,8mm com e sem Hormônio, respectivamente, P>0,05), e na Duração dos estros (57,68±20,02 vs 59,68±14,76 horas, com e sem Hormônio e 57,75±14,99 vs 59,62±19,43 horas, com e sem Flushing, respectivamente, P>0,05). Constatou-se diferença significativa na Viabilidade embrionária (11,55±4,81 vs 8,50±5,32 embriões viáveis, com e sem Flushing e 8,39±5,66 vs 11,25±4,58 embriões viáveis, com e sem Hormônio, respectivamente P=0,02), indicando valor superior para o tratamento com Flushing e inferior no grupo com Hormônio. No Peso final (117,48±9,82 vs 109,28±7,57kg, com e sem Flushing, respectivamente, P=0,0001) e na Espessura de toucinho (10,7±2,2 vs 9,5±1,9kg, com e sem Flushing, respectivamente, P=0,03) o valor superior ficou para o grupo com Flushing. Concluiu-se no estudo a não interação dos efeitos, entre os fatores Hormônio e Flushing . O uso das gonadotrofinas (eCG e LH) reduziu a dispersão de manifestação do segundo estro, sendo efetiva a sua sincronização. O emprego do Flushing no primeiro ciclo estral em marrãs influenciou positivamente a viabilidade embrionária e na associação do eCG e LH mais Flushing não notou-se efeito interativo, identificando-se diminuição da viabilidade embrionária, pela ação hormonal. / The objective of this study, held at the Swine Research Laboratory of the School of Veterinary Medicine and Zootechnology of the Univ. of São Paulo in Pirassununga, São Paulo, was to verify the combined effects of exogenic gonadotropin (eCG and LH) and flushing on the duration and dispersion of the manifestation of initial and second estruses, cyclicity of females, number of ovulations, embryonic viability, and frequency of ovarian cysts. Used for the experiment were 72 pubertal gilts of Pen Ar Lan NAIMA® lineage, with an average age of 157.49±5.01 days, and weight of 96.65±7.70kg. They were distributed in four treatments in a factorial arrangement, with and without flushing, and with and without hormone treatment. The feed used contained 16% CP and 3,286.73 kcal/kg ME. Starting on the seven day of the first estrus, induced with homone, the females with flushing treament received a 50% increase in the amount of the same type feed that they had been receiving. On the sixteenth day of the first estrus the gilts that received hormone treatment were given 600 UI of eCG (Novormon®) and 2.5 mg of LH (Lutopin®), 72 hours later. All the gilts were exposed to boar twice at day, starting on the tenth day and inseminated during the second estrus with heterospermic semen containing 4 x 109 spermatozoon. At slaughter on the fifth day after insemination, the genitals were removed to examine the ovaries and collect the embryos. Interaction between the factors were not observed. The effects that were analyzed separately did not show significant differences in the number of ovulations (14.28±5.06 vs 13.47±5.57 with and without flushing, and 14.60±5.78 vs 13.23±4.83 with and without hormones, respectively, P>0.05), in the frequency of ovarian cysts (22.86% vs 11.11%, with and without flushing and 15.15% vs 18.42% with and without hormones, respectively, P>0.05), during the second estrus (85.71% vs 91.43% with and without flushing and 90.63% vs 86.84% with and without hormones respectively, P>0.05), at final weight (115.35 ± 8.23 vs 111.56 ± 8.30kg, with and without hormones, respectively, P>0.05), in the backfat (10.0±2.0 vs 10.2±1.8mm with and without hormones, respectively, P>0.05), and in the duration of the estruses (57.68±20.02 vs 59.68±14.76 hours, with and without hormones and 57.75±14.99 vs 59.62±19.43 hours, with and without flushing, respectively, P>0.05). A significant difference was found in embryonic viability (11.55±4.81 vs 8.50±5.32 viable embryos, with and without flushing and 8.39±5.66 vs 11.25±4.58 viable embryos with and without hormones, respectively P=0.02), which indicated higher numbers when treated with flushing and lower numbers when treated with hormones. At the final weight (117.48±9.82kg vs. 109.28±7.57kg with and without flushing respectively, P=0.0001) and in the backfat (10.7±12.2 vs 9.5±1.9kg, with and without flushing, respectively, P=0.03) flushing resulted in a higher number. It is concluded in this study that there is a lack of interactive effects between treaments with hormones and flushing. Utilization of gonadotropins (eCG e LH) reduced the dispersion of the second estrus within an effective synchronization. The utilization of flushing in the first estrous cycle in gilts gave positive results as regards to embryonic viability. The association of eCG and LH, plus flushing did not show an interactive effect, and a reduction was identified in embryonic viability based the action of hormones.

O estudo objetivou avaliar num programa biotécnico aplicado a uma granja comercial, os feitos combinados, emprego de gonadotrofinas e aplicação do \"flushing\". As gonadotrofinas empregadas na indução e sincronização do estro à puberdade em marrãs, aliado a ciclicidade até o 4º estro, correspondeu à aplicação ou não da combinação hormonal, 600 UI de eCG (Novormon®, Syntex S. A., Argentina) e após 72 horas, 2,5mg de LH porcino (Lutropin®, Vetrepharm Canadá Inc., Canadá). O \"flushing\" alimentar ou esquema alimentar adotado na granja, foi empregado no ciclo estral que antecedeu a primeira inseminação artificial, ocorrida aos 220 dias de idade das fêmeas. Os parâmetros analisados foram: taxa de concepção (TC), taxa de parto (TP), taxa de aproveitamento (TA) e tamanho de leitegada (TL), sendo esse último representado pelo número de leitões nascidos totais (NT), nascidos vivos (NV), natimortos (NM) e mumificados (MM). Foram utilizadas 119 leitoas híbridas, num delineamento experimental inteiramente casualizado em arranjo fatorial 2x2. O tratamento com hormônio mostrou percentual significativamente maior de fêmeas que manifestaram estro até o 5° dia de início da indução, em comparação com o tratamento somente com o estímulo do macho, 18,33% vs. 5,08%, respectivamente (P=0,0249). No intervalo seguinte de 18 - 30 dias após a indução, considerando variação do ciclo estral de 18 a 25 dias, a combinação hormonal revelou percentual significativamente maior comparado com o estímulo natural do macho, 48,33% vs. 16,94%, respectivamente (P=0,0003). Nos intervalos subseqüentes as diferenças não foram significativas. Não foi detectada interação significativa para os efeitos combinados gonadotrofinas e \"flushing\". Na análise das características em separado, não houve diferença significativa na taxa de concepção para os tratamentos combinação hormonal e estímulo do macho (96,23% vs. 94,00%, respectivamente), e tratamentos com \"flushing\" e esquema alimentar da granja (95,92% vs. 94,44%, respectivamente). Na taxa de parto, os percentuais embora não tenham revelado significância, mostraram diferenças numéricas, sendo o maior valor numérico representado pelo tratamento com hormônio em comparação com o macho, 92,45% vs. 80,00% respectivamente (P=0,0653). Quanto à taxa de aproveitamento das fêmeas, considerando a indução aos 153 dias de idade das marrãs até o parto, da mesma maneira evidenciou-se diferença numérica mostrando o tratamento com hormônio percentual maior em comparação com macho, 81,67% vs. 67,80%, respectivamente (P=0,0815). Não houve diferença significativa nos tratamentos relacionados à aplicação do \"flushing\" e esquema alimentar da granja, 70,00% vs. 79,66%, respectivamente. Não foi evidenciada diferença significativa quanto ao total de nascidos, nascidos vivos, natimortos e mumificados, para os dois fatores. Destacou-se diferença numérica de 0,75 leitões a mais no total de nascidos para o tratamento com hormônio, não havendo diferença significativa quando considerado o fator \"flushing\". A analise econômica feita pelas observações obtidas no presente estudo, considerando taxa de aproveitamento do parto e total de nascidos, destaca benefício financeiro apresentado através do valor presente líquido (VPL) para a combinação hormonal de $1.862,75, enquanto que o tratamento que utilizou indução somente com o macho, revelou um VPL negativo de $2.845,55. Conclui-se que houve efeito positivo das gonadotrofinas (eCG e LH) na indução e sincronização do estro à puberdade o qual pode ser associado, na menor dispersão da ciclicidade das marrãs até o quarto estro, no menor número de fêmeas descartadas até o primeiro parto e na vantagem econômica com base na taxa de aproveitamento das fêmeas até o parto e total de leitões nascidos. / The objective of the study was to investigate in a biotecnical program applied in a commercial breeding unit, the effects of the gonadotrophins (eCG and LH) on puberty estrus inductions and synchronization in gilts followed by their ciclicity. The investigation included the use of flushing on preceding oestrus cycle to first artificial insemination (IA). The traits analised were: conception rate, farrowing rate, the percentage of animals that started the experimental period and stayied to first farrowing, and litter size. The experiment used 119 hybrid gilts on 153 days of age. The experimental design was entirely random in a factorial arrangement 2x2. One factor corresponding to the gonadotrophin (H) application or the male (M) induction only. The hormonal treatment utilized a combination of 600 UI of eCG (Novormon®, Syntex S. A., Argentina) and 72 hours lates, 2,5 mg of LH (Lutropin®, Vetrepharm Canadá Inc., Canadá). The other factor corresponds to the flushing application in a restriction - ad libitum regimen (R) or a flushing application based on a lactation diet offered in an ad libitum regimen in the breeding unit (B). This factor was applied in the oestrus cycle that preceded first artificial insemination, occurring at 220 days of age. Our results identified,18,33% hormonal treatment of females showing apparent estrus compared to 5% in treatment that used only the male induction. From 18 to 30 days after induction, considering the estrus interval variation about 18-25 days, the hormonal treatment showed significant percentage more than the male induction (48,33% vs. 16,94%, respectively). In the following intervals the differences weren\'t statiscally significant. The cumulative percentuals until 30 days and 90 days periods, the values were 71,67% vs. 69,49% and 91,67% vs. 94,92%, respectively, for hormonal treatment and male induction. There wasn\'t significant interation for reproductive traits. There wasn\'t significant difference on the conception rate, when you considered the factors separately, hormonal treatment (H) and male (M) induction (96,23% vs. 94,00%, respectively) and flushing (R) and the regime adapted in the breeding unit (B) (95,92% vs. 94,44%, respectively). While the farrowing rate hasn\'t showed significance, there was umerical differences in favour of hormonal treatment against male induction (92,45 %vs 80,00%, respectively) (P=0,0653). Considering the period since induction (153 days of age) until parturition, the percentual of hormonal treatment group was superior compared to the male induction group (81,67% vs. 67,80%, respectively) (P=0,0815). However, the percentual was some flushing (R) and the regimen assumed in the breeding unit (G) (70,00% vs. 67,80%, respectively). There wasn\'t significant difference related to total born, born alive, stillborn and mummified fetus on both factors. It is important to emphasize the numerical differences of 0,75 total born piglets in favor of the hormonal groups. There wasn\'t any difference on the flushing factor. The economical analyses, considering the period since induction until parturition and total born piglets suggested a financial benify to the hormonal treatment compared to the male induction.

O estudo objetivou avaliar num programa biotécnico aplicado a uma granja comercial, os feitos combinados, emprego de gonadotrofinas e aplicação do \"flushing\". As gonadotrofinas empregadas na indução e sincronização do estro à puberdade em marrãs, aliado a ciclicidade até o 4º estro, correspondeu à aplicação ou não da combinação hormonal, 600 UI de eCG (Novormon®, Syntex S. A., Argentina) e após 72 horas, 2,5mg de LH porcino (Lutropin®, Vetrepharm Canadá Inc., Canadá). O \"flushing\" alimentar ou esquema alimentar adotado na granja, foi empregado no ciclo estral que antecedeu a primeira inseminação artificial, ocorrida aos 220 dias de idade das fêmeas. Os parâmetros analisados foram: taxa de concepção (TC), taxa de parto (TP), taxa de aproveitamento (TA) e tamanho de leitegada (TL), sendo esse último representado pelo número de leitões nascidos totais (NT), nascidos vivos (NV), natimortos (NM) e mumificados (MM). Foram utilizadas 119 leitoas híbridas, num delineamento experimental inteiramente casualizado em arranjo fatorial 2x2. O tratamento com hormônio mostrou percentual significativamente maior de fêmeas que manifestaram estro até o 5° dia de início da indução, em comparação com o tratamento somente com o estímulo do macho, 18,33% vs. 5,08%, respectivamente (P=0,0249). No intervalo seguinte de 18 - 30 dias após a indução, considerando variação do ciclo estral de 18 a 25 dias, a combinação hormonal revelou percentual significativamente maior comparado com o estímulo natural do macho, 48,33% vs. 16,94%, respectivamente (P=0,0003). Nos intervalos subseqüentes as diferenças não foram significativas. Não foi detectada interação significativa para os efeitos combinados gonadotrofinas e \"flushing\". Na análise das características em separado, não houve diferença significativa na taxa de concepção para os tratamentos combinação hormonal e estímulo do macho (96,23% vs. 94,00%, respectivamente), e tratamentos com \"flushing\" e esquema alimentar da granja (95,92% vs. 94,44%, respectivamente). Na taxa de parto, os percentuais embora não tenham revelado significância, mostraram diferenças numéricas, sendo o maior valor numérico representado pelo tratamento com hormônio em comparação com o macho, 92,45% vs. 80,00% respectivamente (P=0,0653). Quanto à taxa de aproveitamento das fêmeas, considerando a indução aos 153 dias de idade das marrãs até o parto, da mesma maneira evidenciou-se diferença numérica mostrando o tratamento com hormônio percentual maior em comparação com macho, 81,67% vs. 67,80%, respectivamente (P=0,0815). Não houve diferença significativa nos tratamentos relacionados à aplicação do \"flushing\" e esquema alimentar da granja, 70,00% vs. 79,66%, respectivamente. Não foi evidenciada diferença significativa quanto ao total de nascidos, nascidos vivos, natimortos e mumificados, para os dois fatores. Destacou-se diferença numérica de 0,75 leitões a mais no total de nascidos para o tratamento com hormônio, não havendo diferença significativa quando considerado o fator \"flushing\". A analise econômica feita pelas observações obtidas no presente estudo, considerando taxa de aproveitamento do parto e total de nascidos, destaca benefício financeiro apresentado através do valor presente líquido (VPL) para a combinação hormonal de $1.862,75, enquanto que o tratamento que utilizou indução somente com o macho, revelou um VPL negativo de $2.845,55. Conclui-se que houve efeito positivo das gonadotrofinas (eCG e LH) na indução e sincronização do estro à puberdade o qual pode ser associado, na menor dispersão da ciclicidade das marrãs até o quarto estro, no menor número de fêmeas descartadas até o primeiro parto e na vantagem econômica com base na taxa de aproveitamento das fêmeas até o parto e total de leitões nascidos. / The objective of the study was to investigate in a biotecnical program applied in a commercial breeding unit, the effects of the gonadotrophins (eCG and LH) on puberty estrus inductions and synchronization in gilts followed by their ciclicity. The investigation included the use of flushing on preceding oestrus cycle to first artificial insemination (IA). The traits analised were: conception rate, farrowing rate, the percentage of animals that started the experimental period and stayied to first farrowing, and litter size. The experiment used 119 hybrid gilts on 153 days of age. The experimental design was entirely random in a factorial arrangement 2x2. One factor corresponding to the gonadotrophin (H) application or the male (M) induction only. The hormonal treatment utilized a combination of 600 UI of eCG (Novormon®, Syntex S. A., Argentina) and 72 hours lates, 2,5 mg of LH (Lutropin®, Vetrepharm Canadá Inc., Canadá). The other factor corresponds to the flushing application in a restriction - ad libitum regimen (R) or a flushing application based on a lactation diet offered in an ad libitum regimen in the breeding unit (B). This factor was applied in the oestrus cycle that preceded first artificial insemination, occurring at 220 days of age. Our results identified,18,33% hormonal treatment of females showing apparent estrus compared to 5% in treatment that used only the male induction. From 18 to 30 days after induction, considering the estrus interval variation about 18-25 days, the hormonal treatment showed significant percentage more than the male induction (48,33% vs. 16,94%, respectively). In the following intervals the differences weren\'t statiscally significant. The cumulative percentuals until 30 days and 90 days periods, the values were 71,67% vs. 69,49% and 91,67% vs. 94,92%, respectively, for hormonal treatment and male induction. There wasn\'t significant interation for reproductive traits. There wasn\'t significant difference on the conception rate, when you considered the factors separately, hormonal treatment (H) and male (M) induction (96,23% vs. 94,00%, respectively) and flushing (R) and the regime adapted in the breeding unit (B) (95,92% vs. 94,44%, respectively). While the farrowing rate hasn\'t showed significance, there was umerical differences in favour of hormonal treatment against male induction (92,45 %vs 80,00%, respectively) (P=0,0653). Considering the period since induction (153 days of age) until parturition, the percentual of hormonal treatment group was superior compared to the male induction group (81,67% vs. 67,80%, respectively) (P=0,0815). However, the percentual was some flushing (R) and the regimen assumed in the breeding unit (G) (70,00% vs. 67,80%, respectively). There wasn\'t significant difference related to total born, born alive, stillborn and mummified fetus on both factors. It is important to emphasize the numerical differences of 0,75 total born piglets in favor of the hormonal groups. There wasn\'t any difference on the flushing factor. The economical analyses, considering the period since induction until parturition and total born piglets suggested a financial benify to the hormonal treatment compared to the male induction.

O objetivo do estudo realizado no Laboratório de Pesquisa em Suínos, da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, Pirassununga – SP, foi verificar os efeitos combinados de gonadotrofinas exógenas, (eCG e LH) e flushing sobre a duração e dispersão da manifestação do primeiro e segundo estros, ciclicidade das fêmeas, número de ovulações, viabilidade embrionária e freqüência de cistos ovarianos. Foram utilizadas 72 marrãs pré-púberes da linhagem Pen Ar Lan NAIMA®, com idade média de 157,49±5,01 dias, e 96,65±7,70kgs de peso, distribuidas em quatro tratamentos, em arranjo fatorial, com e sem flushing , e com e sem hormônio. A ração utilizada continha 16% de PB e 3.286,73 kcal/kg ME. A partir do 7º dia do primeiro estro, induzido com hormônio, as fêmeas do tratamento com flushing receberam 50% de incremento da mesma ração. No 16º dia, após o primeiro estro, as marrãs no tratamento hormonal receberam aplicação de 600 UI de eCG (Novormon®) e 2,5 mg de LH (Lutropin®), 72 horas após. Todas as marrãs foram expostas ao macho duas vezes ao dia, a partir do 10º dia e inseminadas ao segundo estro com sêmem heterospérmico contendo 4 x 109 espermatozóides. Ao abate, realizado no 5º dia após a inseminação, os genitais foram colhidos para exame dos ovários e coleta dos embriões. Não se observou interação entre os fatores. Os efeitos analisados em separado, não evidenciaram diferença significativa no Número de ovulações (14,28±5,06 vs 13,47±5,57 com e sem Flushing e 14,60±5,78 vs 13,23±4,83 com e sem Hormônio, respectivamente, P>0,05), na freqüência de cistos ovarianos (22,86% vs 11,11%, com e sem Flushing e 15,15% vs 18,42%, com e sem Hormônio, respectivamente,. P>0,05), na Manifestação do 2º estro (85,71% vs 91,43% com e sem Flushing e 90,63% vs 86,84% com e sem Hormônio, respectivamente, P>0,05), no Peso Final (115,35±8,23 vs 111,56±8,30kg, com e sem Hormônio, respectivamente, P>0,05), na Espessura de toucinho (10,0±2,0 vs 10,2±1,8mm com e sem Hormônio, respectivamente, P>0,05), e na Duração dos estros (57,68±20,02 vs 59,68±14,76 horas, com e sem Hormônio e 57,75±14,99 vs 59,62±19,43 horas, com e sem Flushing, respectivamente, P>0,05). Constatou-se diferença significativa na Viabilidade embrionária (11,55±4,81 vs 8,50±5,32 embriões viáveis, com e sem Flushing e 8,39±5,66 vs 11,25±4,58 embriões viáveis, com e sem Hormônio, respectivamente P=0,02), indicando valor superior para o tratamento com Flushing e inferior no grupo com Hormônio. No Peso final (117,48±9,82 vs 109,28±7,57kg, com e sem Flushing, respectivamente, P=0,0001) e na Espessura de toucinho (10,7±2,2 vs 9,5±1,9kg, com e sem Flushing, respectivamente, P=0,03) o valor superior ficou para o grupo com Flushing. Concluiu-se no estudo a não interação dos efeitos, entre os fatores Hormônio e Flushing . O uso das gonadotrofinas (eCG e LH) reduziu a dispersão de manifestação do segundo estro, sendo efetiva a sua sincronização. O emprego do Flushing no primeiro ciclo estral em marrãs influenciou positivamente a viabilidade embrionária e na associação do eCG e LH mais Flushing não notou-se efeito interativo, identificando-se diminuição da viabilidade embrionária, pela ação hormonal. / The objective of this study, held at the Swine Research Laboratory of the School of Veterinary Medicine and Zootechnology of the Univ. of São Paulo in Pirassununga, São Paulo, was to verify the combined effects of exogenic gonadotropin (eCG and LH) and flushing on the duration and dispersion of the manifestation of initial and second estruses, cyclicity of females, number of ovulations, embryonic viability, and frequency of ovarian cysts. Used for the experiment were 72 pubertal gilts of Pen Ar Lan NAIMA® lineage, with an average age of 157.49±5.01 days, and weight of 96.65±7.70kg. They were distributed in four treatments in a factorial arrangement, with and without flushing, and with and without hormone treatment. The feed used contained 16% CP and 3,286.73 kcal/kg ME. Starting on the seven day of the first estrus, induced with homone, the females with flushing treament received a 50% increase in the amount of the same type feed that they had been receiving. On the sixteenth day of the first estrus the gilts that received hormone treatment were given 600 UI of eCG (Novormon®) and 2.5 mg of LH (Lutopin®), 72 hours later. All the gilts were exposed to boar twice at day, starting on the tenth day and inseminated during the second estrus with heterospermic semen containing 4 x 109 spermatozoon. At slaughter on the fifth day after insemination, the genitals were removed to examine the ovaries and collect the embryos. Interaction between the factors were not observed. The effects that were analyzed separately did not show significant differences in the number of ovulations (14.28±5.06 vs 13.47±5.57 with and without flushing, and 14.60±5.78 vs 13.23±4.83 with and without hormones, respectively, P>0.05), in the frequency of ovarian cysts (22.86% vs 11.11%, with and without flushing and 15.15% vs 18.42% with and without hormones, respectively, P>0.05), during the second estrus (85.71% vs 91.43% with and without flushing and 90.63% vs 86.84% with and without hormones respectively, P>0.05), at final weight (115.35 ± 8.23 vs 111.56 ± 8.30kg, with and without hormones, respectively, P>0.05), in the backfat (10.0±2.0 vs 10.2±1.8mm with and without hormones, respectively, P>0.05), and in the duration of the estruses (57.68±20.02 vs 59.68±14.76 hours, with and without hormones and 57.75±14.99 vs 59.62±19.43 hours, with and without flushing, respectively, P>0.05). A significant difference was found in embryonic viability (11.55±4.81 vs 8.50±5.32 viable embryos, with and without flushing and 8.39±5.66 vs 11.25±4.58 viable embryos with and without hormones, respectively P=0.02), which indicated higher numbers when treated with flushing and lower numbers when treated with hormones. At the final weight (117.48±9.82kg vs. 109.28±7.57kg with and without flushing respectively, P=0.0001) and in the backfat (10.7±12.2 vs 9.5±1.9kg, with and without flushing, respectively, P=0.03) flushing resulted in a higher number. It is concluded in this study that there is a lack of interactive effects between treaments with hormones and flushing. Utilization of gonadotropins (eCG e LH) reduced the dispersion of the second estrus within an effective synchronization. The utilization of flushing in the first estrous cycle in gilts gave positive results as regards to embryonic viability. The association of eCG and LH, plus flushing did not show an interactive effect, and a reduction was identified in embryonic viability based the action of hormones.