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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Fertility of Beef Recipients Following a Fixed-Time Embryo Transfer Protocol that Includes Follicle Stimulating Hormone Diluted in Hyaluronan

Thorne, Jacob Westley 03 October 2013 (has links)
This study was performed to test the viability of administering a single 40 mg dose of Folltropin-V® (FSH, Bioniche Animal Health) diluted in SRF (MAP-5 50, Sodium Hyaluronate, Bioniche Animal Health) on day 5 of a recipient synchronization protocol to beef cows to evaluate its effect on recipient fertility. All recipients were administered an estradiol 17beta (2.5 mg, IM) and progesterone (50 mg, IM) combination injection on day 0 and a CIDR® (progesterone 1.34 g, Pfizer Animal Health) was inserted. Lutalyse® (dinoprost tromethamine, Pfizer Animal Health, 25 mg, IM) was administered at the time of CIDR removal on day 7, and estradiol 17beta (1 mg, IM) was administered on day 8. On day 16, the presence of at least one corpus luteum (CL), detected via ultrasound, resulted in the recipient receiving an embryo (both fresh and frozen-thawed embryos were used). Embryos were not transferred into cows that did not show the presence of a CL. Dependent variables for which data were collected included circulating progesterone levels at the time of transfer, number of CLs and CL diameter, circumference, and area; measured in millimeters. The study (n=572) consisted of a treatment group (n=268) and a control group (n=304), and included both Bos indicus (Brahman influenced) crossbred (n=115) and Bos taurus (Angus based) cows (n=457). Pregnancy rates for Treated recipients (40.67%A) and Control recipients (52.96%B) differed (P<.05). There was no difference in the mean number of CLs per recipient for Treated (1.14 +/- .03) and Control (1.10 +/- .02) cows, nor was there a difference in progesterone (P4) at the time of transfer for Treated (3.14 +/- .40 ng/mL) and Control (3.23 +/- .18 ng/mL) recipients. Overall, the inclusion of Folltropin-V® diluted in hyaluronan in a FTET synchronization protocol did not improve the fertility of beef recipients.
12

Efeito da concentração do sêmen e horário de inseminação artificial a tempo fixo sobre a prenhez em fêmeas bovinas de corte. / Effect of semen concentration and moment of fixed timed insemination on pregnancy results in beef cattle females

Rocha, Dimas C. January 2007 (has links)
Em experimento conduzido com o objetivo de avaliar os efeitos da concentração da dose de sêmen e o horário da inseminação artificial a tempo pré-fixado, foram utilizadas 516 fêmeas bovinas. Os animais, das raças Aberdeen Angus (Bos taurus) e Braford (Bos taurus 5/8 x Bos indicus 3/8) eram constituídos de 270 novilhas e 246 vacas multíparas. Os animais foram submetidos a um protocolo de sincronização de estros e ovulação através de implante vaginal contendo 250 mg de Acetato de Medroxiprogesterona (MAP) associado a duas aplicações de Benzoato de Estradiol (BE), sendo a primeira de 2 mg IM por ocasião da inserção do implante e a segunda de 1 mg IM vinte e quatro horas após a retirada do mesmo. Quando da remoção do implante foram administrados 500 mcg de Cloprostenol Sódico. As inseminações foram efetuadas às 48, 54 ou 60 horas após a retirada do implante, utilizando para cada momento duas concentrações distintas de espermatozóides viáveis, 10 e 20 milhões por dose. Verificou-se que as fêmeas (em especial as novilhas) inseminadas às 48 horas com 20 milhões de sptz/dose apresentaram índice de prenhez significativamente maior do que as inseminadas no mesmo momento com 10 milhões sptz/dose. As vacas inseminadas com 10 milhões de sptz às 60h apresentaram melhor taxa de prenhez (p<0,05) quando comparadas às inseminadas com 10 milhões de sptz às 48h. O percentual de prenhez encontrado nas vacas foi significativamente maior que o das novilhas, assim como o verificado nas fêmeas Aberdeen Angus, comparadas às Braford. A taxa de prenhez de novilhas inseminadas a tempo fixo pode ser incrementada utilizando-se maior número de espermatozóides viáveis por dose inseminante. / The objective of this study was to analyse the effects of semen concentration and moment of fixed timed insemination on pregnancy rates in 516 beef cattle females of the Aberdeen Angus (Bos taurus) and Braford (Bos taurus 5/8 x Bos indicus 3/8) breeds. The females were constituted of 270 heifers and 246 multiparous cows. The animals were all submitted to a synchronization program consisting of vaginal implants of 250mg of medroxiprogesterone acetate (MPA) associated to application of 2mg IM of estradiol benzoate (EB).After 7 days the implants were removed and 500 mg of cloprostenol were injected at the time. After 24hs of implant removal 1mg IM of EB was injected. The inseminations were done 48, 54 and 60 hours after the removal of the implants and semen with 10 and 20 million viable spermatozoa per dosis was used. The females (specially the heifers) of the group inseminated 48 hours after implant removal and using semen with 20 million viable sptz showed a significant higher percentage of pregnancy than the inseminated 48 hours using 10 million viable sptz. The cows inseminated at 60 hours with 10 million sptz showed higher pregnancy rates (p<0,05) than cows inseminated at 48 hours with 10 million sptz. The total pregnancy rate achieved on the cows was significantly higher than on the heifers. The females of the A. Angus group had higher pregnancy rates than the females of the Braford breed. The pregnancy rate of heifers fixed-timed inseminated can be increased using a higher semen concentration.
13

Efeito da concentração do sêmen e horário de inseminação artificial a tempo fixo sobre a prenhez em fêmeas bovinas de corte. / Effect of semen concentration and moment of fixed timed insemination on pregnancy results in beef cattle females

Rocha, Dimas C. January 2007 (has links)
Em experimento conduzido com o objetivo de avaliar os efeitos da concentração da dose de sêmen e o horário da inseminação artificial a tempo pré-fixado, foram utilizadas 516 fêmeas bovinas. Os animais, das raças Aberdeen Angus (Bos taurus) e Braford (Bos taurus 5/8 x Bos indicus 3/8) eram constituídos de 270 novilhas e 246 vacas multíparas. Os animais foram submetidos a um protocolo de sincronização de estros e ovulação através de implante vaginal contendo 250 mg de Acetato de Medroxiprogesterona (MAP) associado a duas aplicações de Benzoato de Estradiol (BE), sendo a primeira de 2 mg IM por ocasião da inserção do implante e a segunda de 1 mg IM vinte e quatro horas após a retirada do mesmo. Quando da remoção do implante foram administrados 500 mcg de Cloprostenol Sódico. As inseminações foram efetuadas às 48, 54 ou 60 horas após a retirada do implante, utilizando para cada momento duas concentrações distintas de espermatozóides viáveis, 10 e 20 milhões por dose. Verificou-se que as fêmeas (em especial as novilhas) inseminadas às 48 horas com 20 milhões de sptz/dose apresentaram índice de prenhez significativamente maior do que as inseminadas no mesmo momento com 10 milhões sptz/dose. As vacas inseminadas com 10 milhões de sptz às 60h apresentaram melhor taxa de prenhez (p<0,05) quando comparadas às inseminadas com 10 milhões de sptz às 48h. O percentual de prenhez encontrado nas vacas foi significativamente maior que o das novilhas, assim como o verificado nas fêmeas Aberdeen Angus, comparadas às Braford. A taxa de prenhez de novilhas inseminadas a tempo fixo pode ser incrementada utilizando-se maior número de espermatozóides viáveis por dose inseminante. / The objective of this study was to analyse the effects of semen concentration and moment of fixed timed insemination on pregnancy rates in 516 beef cattle females of the Aberdeen Angus (Bos taurus) and Braford (Bos taurus 5/8 x Bos indicus 3/8) breeds. The females were constituted of 270 heifers and 246 multiparous cows. The animals were all submitted to a synchronization program consisting of vaginal implants of 250mg of medroxiprogesterone acetate (MPA) associated to application of 2mg IM of estradiol benzoate (EB).After 7 days the implants were removed and 500 mg of cloprostenol were injected at the time. After 24hs of implant removal 1mg IM of EB was injected. The inseminations were done 48, 54 and 60 hours after the removal of the implants and semen with 10 and 20 million viable spermatozoa per dosis was used. The females (specially the heifers) of the group inseminated 48 hours after implant removal and using semen with 20 million viable sptz showed a significant higher percentage of pregnancy than the inseminated 48 hours using 10 million viable sptz. The cows inseminated at 60 hours with 10 million sptz showed higher pregnancy rates (p<0,05) than cows inseminated at 48 hours with 10 million sptz. The total pregnancy rate achieved on the cows was significantly higher than on the heifers. The females of the A. Angus group had higher pregnancy rates than the females of the Braford breed. The pregnancy rate of heifers fixed-timed inseminated can be increased using a higher semen concentration.
14

Efeito da concentração do sêmen e horário de inseminação artificial a tempo fixo sobre a prenhez em fêmeas bovinas de corte. / Effect of semen concentration and moment of fixed timed insemination on pregnancy results in beef cattle females

Rocha, Dimas C. January 2007 (has links)
Em experimento conduzido com o objetivo de avaliar os efeitos da concentração da dose de sêmen e o horário da inseminação artificial a tempo pré-fixado, foram utilizadas 516 fêmeas bovinas. Os animais, das raças Aberdeen Angus (Bos taurus) e Braford (Bos taurus 5/8 x Bos indicus 3/8) eram constituídos de 270 novilhas e 246 vacas multíparas. Os animais foram submetidos a um protocolo de sincronização de estros e ovulação através de implante vaginal contendo 250 mg de Acetato de Medroxiprogesterona (MAP) associado a duas aplicações de Benzoato de Estradiol (BE), sendo a primeira de 2 mg IM por ocasião da inserção do implante e a segunda de 1 mg IM vinte e quatro horas após a retirada do mesmo. Quando da remoção do implante foram administrados 500 mcg de Cloprostenol Sódico. As inseminações foram efetuadas às 48, 54 ou 60 horas após a retirada do implante, utilizando para cada momento duas concentrações distintas de espermatozóides viáveis, 10 e 20 milhões por dose. Verificou-se que as fêmeas (em especial as novilhas) inseminadas às 48 horas com 20 milhões de sptz/dose apresentaram índice de prenhez significativamente maior do que as inseminadas no mesmo momento com 10 milhões sptz/dose. As vacas inseminadas com 10 milhões de sptz às 60h apresentaram melhor taxa de prenhez (p<0,05) quando comparadas às inseminadas com 10 milhões de sptz às 48h. O percentual de prenhez encontrado nas vacas foi significativamente maior que o das novilhas, assim como o verificado nas fêmeas Aberdeen Angus, comparadas às Braford. A taxa de prenhez de novilhas inseminadas a tempo fixo pode ser incrementada utilizando-se maior número de espermatozóides viáveis por dose inseminante. / The objective of this study was to analyse the effects of semen concentration and moment of fixed timed insemination on pregnancy rates in 516 beef cattle females of the Aberdeen Angus (Bos taurus) and Braford (Bos taurus 5/8 x Bos indicus 3/8) breeds. The females were constituted of 270 heifers and 246 multiparous cows. The animals were all submitted to a synchronization program consisting of vaginal implants of 250mg of medroxiprogesterone acetate (MPA) associated to application of 2mg IM of estradiol benzoate (EB).After 7 days the implants were removed and 500 mg of cloprostenol were injected at the time. After 24hs of implant removal 1mg IM of EB was injected. The inseminations were done 48, 54 and 60 hours after the removal of the implants and semen with 10 and 20 million viable spermatozoa per dosis was used. The females (specially the heifers) of the group inseminated 48 hours after implant removal and using semen with 20 million viable sptz showed a significant higher percentage of pregnancy than the inseminated 48 hours using 10 million viable sptz. The cows inseminated at 60 hours with 10 million sptz showed higher pregnancy rates (p<0,05) than cows inseminated at 48 hours with 10 million sptz. The total pregnancy rate achieved on the cows was significantly higher than on the heifers. The females of the A. Angus group had higher pregnancy rates than the females of the Braford breed. The pregnancy rate of heifers fixed-timed inseminated can be increased using a higher semen concentration.
15

Conformal survival predictions at a user-controlled time point : The introduction of time point specialized Conformal Random Survival Forests

van Miltenburg, Jelle January 2018 (has links)
The goal of this research is to expand the field of conformal predictions using Random Survival Forests. The standard Conformal Random Survival Forest can predict with a fixed certainty whether something will survive up until a certain time point. This research is the first to show that there is little practical use in the standard Conformal Random Survival Forest algorithm. It turns out that the confidence guarantees of the conformal prediction framework are violated if the Standard algorithm makes predictions for a user-controlled fixed time point. To solve this challenge, this thesis proposes two algorithms that specialize in conformal predictions for a fixed point in time: a Fixed Time algorithm and a Hybrid algorithm. Both algorithms transform the survival data that is used by the split evaluation metric in the Random Survival Forest algorithm. The algorithms are evaluated and compared along six different set prediction evaluation criteria. The prediction performance of the Hybrid algorithm outperforms the prediction performance of the Fixed Time algorithm in most cases. Furthermore, the Hybrid algorithm is more stable than the Fixed Time algorithm when the predicting job extends to various time points. The hybrid Conformal Random Survival Forest should thus be considered by anyone who wants to make conformal survival predictions at usercontrolled time points. / Målet med denna avhandling är att utöka området för konformitetsprediktion med hjälp av Random Survival Forests. Standardutförandet av Conformal Random Survival Forest kan förutsäga med en viss säkerhet om någonting kommer att överleva fram till en viss tidpunkt. Denna avhandling är den första som visar att det finns liten praktisk användning i standardutförandet av Conformal Random Survival Forest-algoritmen. Det visar sig att konfidensgarantierna för konformitetsprediktionsramverket bryts om standardalgoritmen gör förutsägelser för en användarstyrd fast tidpunkt. För att lösa denna utmaning, föreslår denna avhandling två algoritmer som specialiserar sig i konformitetsprediktion för en bestämd tidpunkt: en fast-tids algoritm och en hybridalgoritm. Båda algoritmerna omvandlar den överlevnadsdata som används av den delade utvärderingsmetoden i Random Survival Forest-algoritmen. Uppskattningsförmågan för hybridalgoritmen överträffar den för fast-tids algoritmen i de flesta fall. Dessutom är hybrid algoritmen stabilare än fast-tids algoritmen när det förutsägelsejobbet sträcker sig till olika tidpunkter. Hybridalgoritmen för Conformal Random Survival Forest bör därför föredras av den som vill göra konformitetsprediktion av överlevnad vid användarstyrda tidpunkter.
16

Inseminação artificial pós-cervical em tempo fixo em porcas recebendo pLH no início do estro / Fixed-time post cervical artificial insemination in sows receiving pLH at estrus onset

Fontana, Diogo Luiz January 2013 (has links)
Inseminação artificial em tempo fixo (IATF) associada à inseminação artificial pós-cervical (IAPC) permite uma maior utilização de machos geneticamente superiores e uma redução expressiva de mão de obra na produção de suínos. O objetivo deste estudo foi avaliar a eficiência da IATF de acordo com diferentes protocolos de (IA), usando pLH - hormônio luteinizante suíno - como indutor da ovulação. Um total de 597 matrizes desmamadas com detecção de estro realizada uma vez ao dia (08:00) foram alocados em três tratamentos: Controle (n = 199) - primeira inseminação realizada no início do estro (0 h) e repetida a cada 24 h, durante o estro; IATF1 (n = 199) - fêmeas receberam 5 mg (4 ml) i.m. de pLH no início do estro, e foram inseminadas 24 horas depois, e IATF2 (n = 199) – fêmeas receberam 5 mg de pLH mas foram inseminadas no início do estro (0 h) e 24 horas depois. Foram realizadas IAPC com doses homospérmicas (1,5 x 109 de espermatozoides totais/50 ml) em todos os tratamentos. O tratamento hormonal não afetou o intervalo do início do estro à ovulação (P> 0,05). O número de inseminações foi de 2,9, 1,0 e 2,0 para Controle, FTAI1 e FTAI2 respectivamente. Não houve diferença entre os tratamentos para taxa de parto e leitões nascidos totais (P> 0,05). Leitões nascidos totais por dose inseminante foi diferente (P <0,0001) entre os tratamentos (4,5, 12,5 e 6,2 para Controle, FTAI1 e FTAI2 respectivamente). O uso de pLH no início do estro associado à uma única inseminação em tempo fixo IAPC 24 horas após, não comprometeu o desempenho reprodutivo de porcas multíparas. / Fixed-time artificial insemination (FTAI) associated to post cervical artificial insemination (PCAI) allows a wider use of high indexed boars and an expressive reduction on labor requirements in swine production. The aim of this study was to evaluate FTAI efficiency according to different AI protocols, using pLH – porcine luteinizing hormone - as ovulation inductor. A total of 597 weaned sows whose estrus detection was performed once daily (08:00 am) were allocated into three treatments: Control (n= 199) – the first insemination was performed at estrus onset (0 h) and repeated every 24 h thereafter, during estrus; FTAI1 (n= 199) - sows received a 5 mg (4 ml) i.m. injection of pLH at estrus onset, and were inseminated 24 h after, and FTAI2 (n= 199) - sows received 5 mg of pLH but were inseminated at estrus onset (0 h) and 24 h after. PCAI with homospermic doses (1.5 x 109 total sperm cells/50 ml) were performed in all treatments. Hormonal treatment did not affect the interval onset of estrus to ovulation (P>0.05). The number of inseminations was 2.9, 1.0 and 2.0 for Control, FTAI1 and FTAI2 respectively. Treatments did not affect farrowing rate and total born (P>0.05). Total piglets born per insemination dose was different (P<0.0001) among treatments (4.5, 12.5 and 6.2 for Control, FTAI1 and FTAI2 respectively). The use of pLH at estrus onset associated to a single fixed-time PCAI 24 h after does not compromise the reproductive performance of multiparous sows.
17

A utilização de progesterona injetável, pós inseminação artificial em tempo fixo, em vacas de leite de alta produção como estratégia para melhoria da eficiência reprodutiva em propriedade leiteira / The use of injetable progesterone after time fixed artificial insemination in high producing dairy cows as a strategy to improve the reproductive eficience in dairy farm

Tortorelli, Gabriela 14 December 2018 (has links)
Com o intuito de contribuir para a melhoria da eficiência na reprodução de vacas leiteiras de alta produção, objetivou-se no presente trabalho avaliar a taxa de concepção (TC) e a perda gestacional precoce (PGP) em vacas da raça Holandesa suplementadas com 900 mg de progesterona injetável de longa ação, quatro dias após Inseminação Artificial em Tempo Fixo (IATF) em relação ao grupo controle. A pesquisa foi desenvolvida em rebanho leiteiro comercial na cidade de Descalvado-SP, durante o período de janeiro de 2016 até janeiro de 2017, resultando em um total de 1.414 protocolos de IATF, sendo 708 do grupo experimental com progesterona (G1) e 706 do grupo controle (G2). Não houve diferença na TC aos 30 (p=0,276) e aos 60 dias (p=0,215) de G1 em relação a G2. Houve diferença significativa PGP (p=0,007), em que foi possível aferir que vacas tratadas com progesterona pós-IATF tiveram 2,1 vezes mais chance de perderem a gestação em relação àquelas do grupo controle. Foi realizado teste de regressão logística para os subgrupos que foram ao final significativos para efeito de progesterona: Vacas (G1) com 1-4 inseminações, primíparas, no inverno obtiveram 63% menos chance de se tornarem prenhes aos 30 dias. Vacas com mais de 4 inseminações no verão obtiveram 2,5 vezes mais chance de se tornarem prenhes aos 30 dias e 2,6 vezes mais chance de se tornarem prenhes aos 60 dias. Conclui-se que a utilização indiscriminada de progesterona injetável pós-IATF neste estudo não trouxe melhoria em TC30 e TC60 e houve aumento de PGP. No entanto, pode-se afirmar que a suplementação de progesterona influencia positivamente as TC30 e TC60 para a classe de vacas com mais de 4 inseminações no período do verão. / To improve the reproductive efficiency of high production dairy cows, the aim of the present study was to evaluate the conception rate of Holstein cows of high production supplemented with 900 mg of long acting injectable progesterone, four days after FTAI and Early Pregnancy Loss (EPL) comparing it to the control group. The project is a result of information collected from a commercial dairy herd from Descalvado-SP, during January 2016 until January 2017, totalizing 1414 FTAI protocols, 708 within the experimental group with progesterone supplementation (G1) and 706 within the control group (G2). There was no statistical difference in conception rate at 30 days (CR30) (p = 0.276) and conception rate at 60 days (CR60) (p = 0.215) between G1 and G2. There was a significant difference in the EPL (p = 0.007), which was possible to ascertain that cows treated with progesterone after FTAI were 2.1 times more likely to lose pregnancy than those in the control group. A logistic regression test was performed to evaluate the interaction of classes and those relations to progesterone, within the values of p &lt;0.1 considered for group subdivisions. Among the subgroups that were significant for progesterone effect: Cows that received 1 to 4 inseminations primiparous in the winter, for CR30 (p = 0.009); Cows with 5 or more inseminations in the summer for CR30 (p = 0.004) and CR60 (p = 0.008). Cows with 1-4 inseminations, primiparous, in the winter were 63% less likely to become pregnant at 30 days. Cows with more than 4 inseminations in the summer were 2.5 times more likely to become pregnant at 30 days and 2.6 times more likely to become pregnant at 60 days. It was concluded that the indiscriminate use of injectable progesterone after FTAI in this study did not bring improvement in CR30 neither CR60 and the reproductive efficiency was decreased, with increase of EPL. It is possible to hold true that that progesterone supplementation at 4th day after FTAI positively influences the CR30 and CR60 among the cows within the class with more than 4 inseminations in the summer.
18

Inseminação artificial pós-cervical em tempo fixo em porcas recebendo pLH no início do estro / Fixed-time post cervical artificial insemination in sows receiving pLH at estrus onset

Fontana, Diogo Luiz January 2013 (has links)
Inseminação artificial em tempo fixo (IATF) associada à inseminação artificial pós-cervical (IAPC) permite uma maior utilização de machos geneticamente superiores e uma redução expressiva de mão de obra na produção de suínos. O objetivo deste estudo foi avaliar a eficiência da IATF de acordo com diferentes protocolos de (IA), usando pLH - hormônio luteinizante suíno - como indutor da ovulação. Um total de 597 matrizes desmamadas com detecção de estro realizada uma vez ao dia (08:00) foram alocados em três tratamentos: Controle (n = 199) - primeira inseminação realizada no início do estro (0 h) e repetida a cada 24 h, durante o estro; IATF1 (n = 199) - fêmeas receberam 5 mg (4 ml) i.m. de pLH no início do estro, e foram inseminadas 24 horas depois, e IATF2 (n = 199) – fêmeas receberam 5 mg de pLH mas foram inseminadas no início do estro (0 h) e 24 horas depois. Foram realizadas IAPC com doses homospérmicas (1,5 x 109 de espermatozoides totais/50 ml) em todos os tratamentos. O tratamento hormonal não afetou o intervalo do início do estro à ovulação (P> 0,05). O número de inseminações foi de 2,9, 1,0 e 2,0 para Controle, FTAI1 e FTAI2 respectivamente. Não houve diferença entre os tratamentos para taxa de parto e leitões nascidos totais (P> 0,05). Leitões nascidos totais por dose inseminante foi diferente (P <0,0001) entre os tratamentos (4,5, 12,5 e 6,2 para Controle, FTAI1 e FTAI2 respectivamente). O uso de pLH no início do estro associado à uma única inseminação em tempo fixo IAPC 24 horas após, não comprometeu o desempenho reprodutivo de porcas multíparas. / Fixed-time artificial insemination (FTAI) associated to post cervical artificial insemination (PCAI) allows a wider use of high indexed boars and an expressive reduction on labor requirements in swine production. The aim of this study was to evaluate FTAI efficiency according to different AI protocols, using pLH – porcine luteinizing hormone - as ovulation inductor. A total of 597 weaned sows whose estrus detection was performed once daily (08:00 am) were allocated into three treatments: Control (n= 199) – the first insemination was performed at estrus onset (0 h) and repeated every 24 h thereafter, during estrus; FTAI1 (n= 199) - sows received a 5 mg (4 ml) i.m. injection of pLH at estrus onset, and were inseminated 24 h after, and FTAI2 (n= 199) - sows received 5 mg of pLH but were inseminated at estrus onset (0 h) and 24 h after. PCAI with homospermic doses (1.5 x 109 total sperm cells/50 ml) were performed in all treatments. Hormonal treatment did not affect the interval onset of estrus to ovulation (P>0.05). The number of inseminations was 2.9, 1.0 and 2.0 for Control, FTAI1 and FTAI2 respectively. Treatments did not affect farrowing rate and total born (P>0.05). Total piglets born per insemination dose was different (P<0.0001) among treatments (4.5, 12.5 and 6.2 for Control, FTAI1 and FTAI2 respectively). The use of pLH at estrus onset associated to a single fixed-time PCAI 24 h after does not compromise the reproductive performance of multiparous sows.
19

Inseminação artificial pós-cervical em tempo fixo em porcas recebendo pLH no início do estro / Fixed-time post cervical artificial insemination in sows receiving pLH at estrus onset

Fontana, Diogo Luiz January 2013 (has links)
Inseminação artificial em tempo fixo (IATF) associada à inseminação artificial pós-cervical (IAPC) permite uma maior utilização de machos geneticamente superiores e uma redução expressiva de mão de obra na produção de suínos. O objetivo deste estudo foi avaliar a eficiência da IATF de acordo com diferentes protocolos de (IA), usando pLH - hormônio luteinizante suíno - como indutor da ovulação. Um total de 597 matrizes desmamadas com detecção de estro realizada uma vez ao dia (08:00) foram alocados em três tratamentos: Controle (n = 199) - primeira inseminação realizada no início do estro (0 h) e repetida a cada 24 h, durante o estro; IATF1 (n = 199) - fêmeas receberam 5 mg (4 ml) i.m. de pLH no início do estro, e foram inseminadas 24 horas depois, e IATF2 (n = 199) – fêmeas receberam 5 mg de pLH mas foram inseminadas no início do estro (0 h) e 24 horas depois. Foram realizadas IAPC com doses homospérmicas (1,5 x 109 de espermatozoides totais/50 ml) em todos os tratamentos. O tratamento hormonal não afetou o intervalo do início do estro à ovulação (P> 0,05). O número de inseminações foi de 2,9, 1,0 e 2,0 para Controle, FTAI1 e FTAI2 respectivamente. Não houve diferença entre os tratamentos para taxa de parto e leitões nascidos totais (P> 0,05). Leitões nascidos totais por dose inseminante foi diferente (P <0,0001) entre os tratamentos (4,5, 12,5 e 6,2 para Controle, FTAI1 e FTAI2 respectivamente). O uso de pLH no início do estro associado à uma única inseminação em tempo fixo IAPC 24 horas após, não comprometeu o desempenho reprodutivo de porcas multíparas. / Fixed-time artificial insemination (FTAI) associated to post cervical artificial insemination (PCAI) allows a wider use of high indexed boars and an expressive reduction on labor requirements in swine production. The aim of this study was to evaluate FTAI efficiency according to different AI protocols, using pLH – porcine luteinizing hormone - as ovulation inductor. A total of 597 weaned sows whose estrus detection was performed once daily (08:00 am) were allocated into three treatments: Control (n= 199) – the first insemination was performed at estrus onset (0 h) and repeated every 24 h thereafter, during estrus; FTAI1 (n= 199) - sows received a 5 mg (4 ml) i.m. injection of pLH at estrus onset, and were inseminated 24 h after, and FTAI2 (n= 199) - sows received 5 mg of pLH but were inseminated at estrus onset (0 h) and 24 h after. PCAI with homospermic doses (1.5 x 109 total sperm cells/50 ml) were performed in all treatments. Hormonal treatment did not affect the interval onset of estrus to ovulation (P>0.05). The number of inseminations was 2.9, 1.0 and 2.0 for Control, FTAI1 and FTAI2 respectively. Treatments did not affect farrowing rate and total born (P>0.05). Total piglets born per insemination dose was different (P<0.0001) among treatments (4.5, 12.5 and 6.2 for Control, FTAI1 and FTAI2 respectively). The use of pLH at estrus onset associated to a single fixed-time PCAI 24 h after does not compromise the reproductive performance of multiparous sows.
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Modeling land-cover change in the Amazon using historical pathways of land cover change and Markov chains. A case study of Rondõnia, Brazil

Becerra-Cordoba, Nancy 15 August 2008 (has links)
The present dissertation research has three purposes: the first one is to predict anthropogenic deforestation caused by small farmers firstly using only pathways of past land cover change and secondly using demographic, socioeconomic and land cover data at the farm level. The second purpose is to compare the explanatory and predictive capacity of both approaches at identifying areas at high risk of deforestation among small farms in Rondõnia, Brazil. The third purpose is to test the assumptions of stationary probabilities and homogeneous subjects, both commonly used assumptions in predictive stochastic models applied to small farmers' deforestation decisions. This study uses the following data: household surveys, maps, satellite images and their land cover classification at the pixel level, and pathways of past land cover change for each farm. These data are available for a panel sample of farms in three municipios in Rondõnia, Brazil (Alto Paraiso, Nova União, and Rolim de Moura) and cover a ten-year period of study (1992-2002). Pathways of past land cover change are graphic representations in the form of flow charts that depict Land Cover Change (LCC) in each farm during the ten-year period of study. Pathways were constructed using satellite images, survey data and maps, and a set of interviews performed on a sub-sample of 70 farms. A panel data analysis of the estimated empirical probabilities was conducted to test for subject and time effects using a Fixed Group Effects Model (FGEM), specifically the Least Square Dummy Variable (LSDV1) fixed effects technique. Finally, the two predictive modeling approaches are compared. The first modeling approach predicts future LCC using only past land cover change data in the form of empirical transitional probabilities of LCC obtained from pathways of past LCC. These empirical probabilities are used in a LSDV1 for fixed–group effects, a LSDV1 for fixed-time effects, and an Ordinary Least Square model (OLS) for the pooled sample. Results from these models are entered in a modified Markov chain model's matrix multiplication. The second modeling approach predicts future LCC using socio-demographic and economic survey variables at the household level. The survey data is used to perform a multinomial logit regression model to predict the LC class of each pixel. In order to compare the explanatory and predictive capacity of both modeling approaches, LCC predictions at the pixel level are summarized in terms of percentage of cells in which future LC was predicted correctly. Percentage of correct predicted land cover class is compared against actual pixel classification from satellite images. The presence of differences among farmers in the LSDV1-fixed group effect by farmer suggests that small farmers are not a homogeneous group in term of their probabilities of LCC and that further classification of farmers into homogeneous subgroups will depict better their LCC decisions. Changes in the total area of landholdings proved a stronger influence in farmer's LCC decisions in their main property (primary lot) when compared to changes in the area of the primary lot. Panel data analysis of the LCC empirical transition probabilities (LSDV1 fixed time effects model) does not find enough evidence to prefer the fixed time effects model when compared to a Ordinary Least Square (OLS) pooled version of the probabilities. When applying the results of the panel data analysis to a modified markov chain model the LSDV1-farmer model provided a slightly better accuracy (59.25% accuracy) than the LSDV1-time and the OLS-pooled models (57.54% and 57.18%, respectively). The main finding for policy and planning purposes is that owners type 1—with stable total landholdings over time—tend to preserve forest with a much higher probability (0.9033) than owner with subdividing or expanding properties (probs. of 0.0013 and 0.0030). The main implication for policy making and planning is to encourage primary forest preservation, given that the Markov chain analysis shows that primary forest changes into another land cover, it will never go back to this original land cover class. Policy and planning recommendations are provided to encourage owner type 1 to continue their pattern of high forest conservation rates. Some recommendations include: securing land titling, providing health care and alternative sources of income for the OT1's family members and elderly owners to remain in the lot. Future research is encouraged to explore spatial autocorrelation in the pixel's probabilities of land cover change, effects of local policies and macro-economic variables in the farmer's LCC decisions. / Ph. D.

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