Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte
Autor(a) principal: | |
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Data de Publicação: | 2002 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Biblioteca Digital de Teses e Dissertações do UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/26708 |
Resumo: | The objective of the first experiment was to compare the efficiency of a hormonal protocol, associated to the temporary weaning for 96 hours, with the definitive weaning at 60 days for induction of estrus and ovulation, considering a molecular marker BMS3004. There were used 181 suckled beef cows, from Charolais (C) and Nellore (N) breeds and their crosses. These cows were genotyped as homozygous (HOM) and heterozigous (HET) for the microsatellite BMS3004, which is localized in the same chromosome that expresses the LH chain gene. In the day 0 (between 60 and 80 days postpartum), the cows were distributed in two groups. In the hormonal induction group (HI), the cows (n=87) received an intravaginal device (IVD), containing 250mg of medroxiprogesteron acetate (MAP). On day 1, it was injected, intramuscularly (im), 2.5mg of estradiol benzoate (EB) and, on day 7, 500UI (im) of equine chorionic gonadotrophin (eCG). On day 8, the IVD were withdrawn and the calves were weaned for 96 hours. On day 8, the cows (n=96) of the other group were only submitted to early definitive weaning (group EW). Twelve hours after weaning, artificial insemination (AI) was done during four days. After this period, they were mated. The cows of HI group were definitively weaned 26 days after the AI period. The first diagnosis of pregnancy (DP) was done 60 days after the AI period and, the second, 60 days after the end of mating. At day 0, the cows presented body condition (BC) between 2.0 and 3.5 (scale from 1 to 5) and body index (BI) from 47 to 73. The estrus rate was higher in cows from HI group than in those of EW group. The cows with BC 2.5 and 3.0 presented lower (P<0.05) pregnancy rates at 1st DP in the HI group (29.6% and 46.4%) than in the EW group (56.0% and 72.2%). The rates of pregnancy in cows with BI 65-73 did not differ (P>0.05) between the HI and EW groups. The N cows of HI group presented lower (P<0.05) pregnancy rate at 1st DP than the ½ blood (27.7% vs. 64.2%), but they were not different (P>0.05) than the C breed (40.0%). In the HI group, the pregnancy rate at 2nd DP was lower (P<0.05) in HOM cows than HET ones. In this experiment, the early definitive weaning was more efficient than the hormonal induction to improve pregnancy rate. Based in these results, another experiment was designed to develop and evaluate a protocol for inducing ovulation and inseminating suckled beef cows under nutritional stress. A total of 137 cows, between 60 and 75 days postpartum (day 0), were classified according to their BC and distributed in two groups. In the hormonal induction group (HI), the cows (n=71) received an IVD with 250mg of MAP and 2.5mg of EB (im). On day 6, a dose of 500IU of eCG was injected (im) and the calves were temporarily weaned for 96 hours. On the following day (day 7), the IVD were removed. The cows were inseminated 12 hours after estrus detection until 45 hours after removing the IVD. In the cows that did not show estrus during this period, it was injected (im) 100g of GnRH and fixed time AI was done from 16 to 18 hours. In the control group (C), the cows (n=66) had only theirs calves weaned at day 6 for 96 hours. The diagnosis of pregnancy was performed in a mean of 54 days after the AI period. On day 0, all the cows were under nutritional stress (BC from 2.0 to 3.0). In the HI group, the estrus and pregnancy rate of the cows with BC 2.0 (respectively 20.0% and 30.0%) was lower (P<0.05) than those with BC 3.0 (50.0% and 66.6%), but did not differ (P>0.05) from BC 2.5 (23.3% and 47.6%). In the C group, just 2 out of 64 cows showed estrus and were inseminated, but did not result in pregnancy. These results show that the hormonal induction of ovulation, associated to temporary weaning for 96 hours, improves the pregnancy rate in beef cows under nutritional stress between 60 and 75 days postpartum, allowing a three-days period of AI. |
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2022-10-31T15:17:23Z2022-10-31T15:17:23Z2002-02-20http://repositorio.ufsm.br/handle/1/26708The objective of the first experiment was to compare the efficiency of a hormonal protocol, associated to the temporary weaning for 96 hours, with the definitive weaning at 60 days for induction of estrus and ovulation, considering a molecular marker BMS3004. There were used 181 suckled beef cows, from Charolais (C) and Nellore (N) breeds and their crosses. These cows were genotyped as homozygous (HOM) and heterozigous (HET) for the microsatellite BMS3004, which is localized in the same chromosome that expresses the LH chain gene. In the day 0 (between 60 and 80 days postpartum), the cows were distributed in two groups. In the hormonal induction group (HI), the cows (n=87) received an intravaginal device (IVD), containing 250mg of medroxiprogesteron acetate (MAP). On day 1, it was injected, intramuscularly (im), 2.5mg of estradiol benzoate (EB) and, on day 7, 500UI (im) of equine chorionic gonadotrophin (eCG). On day 8, the IVD were withdrawn and the calves were weaned for 96 hours. On day 8, the cows (n=96) of the other group were only submitted to early definitive weaning (group EW). Twelve hours after weaning, artificial insemination (AI) was done during four days. After this period, they were mated. The cows of HI group were definitively weaned 26 days after the AI period. The first diagnosis of pregnancy (DP) was done 60 days after the AI period and, the second, 60 days after the end of mating. At day 0, the cows presented body condition (BC) between 2.0 and 3.5 (scale from 1 to 5) and body index (BI) from 47 to 73. The estrus rate was higher in cows from HI group than in those of EW group. The cows with BC 2.5 and 3.0 presented lower (P<0.05) pregnancy rates at 1st DP in the HI group (29.6% and 46.4%) than in the EW group (56.0% and 72.2%). The rates of pregnancy in cows with BI 65-73 did not differ (P>0.05) between the HI and EW groups. The N cows of HI group presented lower (P<0.05) pregnancy rate at 1st DP than the ½ blood (27.7% vs. 64.2%), but they were not different (P>0.05) than the C breed (40.0%). In the HI group, the pregnancy rate at 2nd DP was lower (P<0.05) in HOM cows than HET ones. In this experiment, the early definitive weaning was more efficient than the hormonal induction to improve pregnancy rate. Based in these results, another experiment was designed to develop and evaluate a protocol for inducing ovulation and inseminating suckled beef cows under nutritional stress. A total of 137 cows, between 60 and 75 days postpartum (day 0), were classified according to their BC and distributed in two groups. In the hormonal induction group (HI), the cows (n=71) received an IVD with 250mg of MAP and 2.5mg of EB (im). On day 6, a dose of 500IU of eCG was injected (im) and the calves were temporarily weaned for 96 hours. On the following day (day 7), the IVD were removed. The cows were inseminated 12 hours after estrus detection until 45 hours after removing the IVD. In the cows that did not show estrus during this period, it was injected (im) 100g of GnRH and fixed time AI was done from 16 to 18 hours. In the control group (C), the cows (n=66) had only theirs calves weaned at day 6 for 96 hours. The diagnosis of pregnancy was performed in a mean of 54 days after the AI period. On day 0, all the cows were under nutritional stress (BC from 2.0 to 3.0). In the HI group, the estrus and pregnancy rate of the cows with BC 2.0 (respectively 20.0% and 30.0%) was lower (P<0.05) than those with BC 3.0 (50.0% and 66.6%), but did not differ (P>0.05) from BC 2.5 (23.3% and 47.6%). In the C group, just 2 out of 64 cows showed estrus and were inseminated, but did not result in pregnancy. These results show that the hormonal induction of ovulation, associated to temporary weaning for 96 hours, improves the pregnancy rate in beef cows under nutritional stress between 60 and 75 days postpartum, allowing a three-days period of AI.Inicialmente, objetivou-se comparar a eficiência de um programa hormonal associado ao desmame temporário por 96 horas, na indução do estro e da ovulação, com o desmame definitivo aos 60 dias em vacas de corte. Foram utilizadas 181 vacas amamentando, das raças Charolês (C), Nelore (N) e suas cruzas recíprocas, as quais foram genotipadas como homozigotas (HOM) ou heterozigotas (HET) para o microssatélite (STR) BMS3004, que está localizado no mesmo cromossomo do gene que codifica para a cadeia do hormônio luteinizante (LH). No dia 0 (entre 60 e 80 dias pós-parto), as vacas foram distribuídas em dois grupos. No grupo indução hormonal (IH), as vacas (n= 87) receberam um pessário intra-vaginal (PIV) contendo 250mg de acetato de medroxiprogesterona (MAP). No dia 1, foram aplicadas (im) 2,5mg de benzoato de estradiol (BE) e, no dia 7, 500UI (im) de gonadotrofina coriônica eqüina (eCG). No dia 8, os PIV foram retirados e os terneiros desmamados por 96 horas. Também no dia 8, as vacas (n=96) do outro grupo foram unicamente submetidas ao desmame definitivo precoce (grupo DP). Após, procedeu-se 4 dias de observação de cios e inseminação artificial (IA) e, então, foram entouradas. As vacas do grupo IH foram desmamadas definitivamente 26 dias após o período de IA. O primeiro diagnóstico de gestação (DG) foi realizado 60 dias após o período de IA e, o segundo, 60 dias após o final do entoure. No dia 0, as vacas apresentaram condição corporal (CC) entre 2,0 e 3,5 (escala de 1 a 5) e índice corporal (IC) entre 47 e 73. As taxas de estro foram maiores nas vacas do grupo IH em relação as do grupo DP. As vacas com CC 2,5 e CC 3,0 apresentaram menores (P<0,05) percentuais de prenhez ao 1ºDG no grupo IH (29,6% e 46,4%) em relação ao grupo DP (56,0% e 72,2%). Os percentuais de prenhez das vacas com IC 65-73 não diferiram (P>0,05) entre os grupos IH e DP. As vacas N do grupo IH, apresentaram menor (P<0,05) percentual de prenhez ao 1ºDG que as ½ sangue (27,7% vs. 64,2%), mas não diferiram (P>0,05) em relação as C (40,0%). No grupo IH, o percentual de prenhez ao 2ºDG foi menor (P<0,05) nas vacas HOM do que nas HET. Nesse experimento, o desmame definitivo, em média, aos 70 dias pós-parto, mostrou-se mais eficaz no incremento dos percentuais de prenhez. A partir desses resultados, outro experimento foi realizado com o objetivo de desenvolver um programa para indução da ovulação e inseminação em vacas de corte amamentando, em estresse nutricional. Entre 60 e 75 dias pós-parto (dia 0), um total de 137 vacas foram classificadas de acordo com sua CC e distribuídas em dois grupos. No grupo Indução Hormonal (IH), as vacas (n=71) receberam um PIV com 250mg de MAP e 2,5mg de BE (im). No dia 6, foram injetadas (im) 500UI de eCG e os terneiros foram desmamados por 96 horas. No dia seguinte (dia 7), os PIV foram removidos. As vacas que demonstraram estro até 45 horas após a remoção dos PIV foram inseminadas 12 horas após a detecção do estro. Nas demais, foram aplicadas (im) 100g de GnRH e, entre 16 a 18 horas, efetuada a IA pré-fixada. No grupo controle (C), as vacas (n=66) unicamente tiveram seus terneiros desmamados a partir do dia 6, por 96 horas. O DG foi realizado, em média, 54 dias após o período de IA. No dia 0, todas as vacas estavam em estresse nutricional (CC entre 2 e 3). No grupo IH, as taxas de estro e prenhez das vacas com CC2,0 (respectivamente, 20,0% e 30,0%) foram menores (P<0,05) do que aquelas com CC3,0 (50,0% e 66,6%), mas não diferiram (P>0,05) das com CC2,5 (23,8% e 47,6%). No grupo C, apenas 2 de 64 vacas demonstraram estro e foram inseminadas, mas não resultaram prenhes. Esses resultados demostram que o programa para indução da ovulação contendo progestágeno, BE, eCG e GnRH, associado ao desmame temporário por 96 horas, aumenta a taxa de prenhez em vacas de corte que se encontram em estresse nutricional entre 60 e 75 dias pós-parto, mediante três dias de IA.porUniversidade Federal de Santa MariaCentro de Ciências RuraisPrograma de Pós-Graduação em Medicina VeterináriaUFSMBrasilMedicina VeterináriaAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessIndução hormonalPós-partoFertilidade animalDesmameGado de corteOvulaçãoReprodução animalNutrição animalBovinosCNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIAInfluência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corteInfluence of the nutritional stress and the molecular marker BMS3004 on the induction of ovulation during postpartum period in beef cowsinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisGoncalves, Paulo Bayard Diashttp://lattes.cnpq.br/5837260966665885Pimentel, Cláudio AlvesDeschamps, João Carloshttp://lattes.cnpq.br/5292926299421569Bastos, Guilherme de Medeiros50050000000760060060060060039e380be-dcb6-45dc-96d0-ad18ba64f2b369cf82ac-918f-4d44-b4ef-73fcb4d1db4a17767a8a-150b-4ffd-8a94-30d85af116aa0744e1c2-1c80-4fc1-95b0-9af3cc43289areponame:Biblioteca Digital de Teses e Dissertações do UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSMORIGINALDIS_PPGMV_2002_BASTOS_GUILHERME.pdfDIS_PPGMV_2002_BASTOS_GUILHERME.pdfDissertação de mestradoapplication/pdf1088595http://repositorio.ufsm.br/bitstream/1/26708/1/DIS_PPGMV_2002_BASTOS_GUILHERME.pdf60598707d71381166a26a8efc6883089MD51CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; 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dc.title.por.fl_str_mv |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte |
dc.title.alternative.eng.fl_str_mv |
Influence of the nutritional stress and the molecular marker BMS3004 on the induction of ovulation during postpartum period in beef cows |
title |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte |
spellingShingle |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte Bastos, Guilherme de Medeiros Indução hormonal Pós-parto Fertilidade animal Desmame Gado de corte Ovulação Reprodução animal Nutrição animal Bovinos CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA |
title_short |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte |
title_full |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte |
title_fullStr |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte |
title_full_unstemmed |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte |
title_sort |
Influência do estresse nutricional e do marcador molecular BMS3004 na indução da ovulação pós-parto em vacas de corte |
author |
Bastos, Guilherme de Medeiros |
author_facet |
Bastos, Guilherme de Medeiros |
author_role |
author |
dc.contributor.advisor1.fl_str_mv |
Goncalves, Paulo Bayard Dias |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/5837260966665885 |
dc.contributor.referee1.fl_str_mv |
Pimentel, Cláudio Alves |
dc.contributor.referee2.fl_str_mv |
Deschamps, João Carlos |
dc.contributor.authorLattes.fl_str_mv |
http://lattes.cnpq.br/5292926299421569 |
dc.contributor.author.fl_str_mv |
Bastos, Guilherme de Medeiros |
contributor_str_mv |
Goncalves, Paulo Bayard Dias Pimentel, Cláudio Alves Deschamps, João Carlos |
dc.subject.por.fl_str_mv |
Indução hormonal Pós-parto Fertilidade animal Desmame Gado de corte Ovulação Reprodução animal Nutrição animal Bovinos |
topic |
Indução hormonal Pós-parto Fertilidade animal Desmame Gado de corte Ovulação Reprodução animal Nutrição animal Bovinos CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA |
dc.subject.cnpq.fl_str_mv |
CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA |
description |
The objective of the first experiment was to compare the efficiency of a hormonal protocol, associated to the temporary weaning for 96 hours, with the definitive weaning at 60 days for induction of estrus and ovulation, considering a molecular marker BMS3004. There were used 181 suckled beef cows, from Charolais (C) and Nellore (N) breeds and their crosses. These cows were genotyped as homozygous (HOM) and heterozigous (HET) for the microsatellite BMS3004, which is localized in the same chromosome that expresses the LH chain gene. In the day 0 (between 60 and 80 days postpartum), the cows were distributed in two groups. In the hormonal induction group (HI), the cows (n=87) received an intravaginal device (IVD), containing 250mg of medroxiprogesteron acetate (MAP). On day 1, it was injected, intramuscularly (im), 2.5mg of estradiol benzoate (EB) and, on day 7, 500UI (im) of equine chorionic gonadotrophin (eCG). On day 8, the IVD were withdrawn and the calves were weaned for 96 hours. On day 8, the cows (n=96) of the other group were only submitted to early definitive weaning (group EW). Twelve hours after weaning, artificial insemination (AI) was done during four days. After this period, they were mated. The cows of HI group were definitively weaned 26 days after the AI period. The first diagnosis of pregnancy (DP) was done 60 days after the AI period and, the second, 60 days after the end of mating. At day 0, the cows presented body condition (BC) between 2.0 and 3.5 (scale from 1 to 5) and body index (BI) from 47 to 73. The estrus rate was higher in cows from HI group than in those of EW group. The cows with BC 2.5 and 3.0 presented lower (P<0.05) pregnancy rates at 1st DP in the HI group (29.6% and 46.4%) than in the EW group (56.0% and 72.2%). The rates of pregnancy in cows with BI 65-73 did not differ (P>0.05) between the HI and EW groups. The N cows of HI group presented lower (P<0.05) pregnancy rate at 1st DP than the ½ blood (27.7% vs. 64.2%), but they were not different (P>0.05) than the C breed (40.0%). In the HI group, the pregnancy rate at 2nd DP was lower (P<0.05) in HOM cows than HET ones. In this experiment, the early definitive weaning was more efficient than the hormonal induction to improve pregnancy rate. Based in these results, another experiment was designed to develop and evaluate a protocol for inducing ovulation and inseminating suckled beef cows under nutritional stress. A total of 137 cows, between 60 and 75 days postpartum (day 0), were classified according to their BC and distributed in two groups. In the hormonal induction group (HI), the cows (n=71) received an IVD with 250mg of MAP and 2.5mg of EB (im). On day 6, a dose of 500IU of eCG was injected (im) and the calves were temporarily weaned for 96 hours. On the following day (day 7), the IVD were removed. The cows were inseminated 12 hours after estrus detection until 45 hours after removing the IVD. In the cows that did not show estrus during this period, it was injected (im) 100g of GnRH and fixed time AI was done from 16 to 18 hours. In the control group (C), the cows (n=66) had only theirs calves weaned at day 6 for 96 hours. The diagnosis of pregnancy was performed in a mean of 54 days after the AI period. On day 0, all the cows were under nutritional stress (BC from 2.0 to 3.0). In the HI group, the estrus and pregnancy rate of the cows with BC 2.0 (respectively 20.0% and 30.0%) was lower (P<0.05) than those with BC 3.0 (50.0% and 66.6%), but did not differ (P>0.05) from BC 2.5 (23.3% and 47.6%). In the C group, just 2 out of 64 cows showed estrus and were inseminated, but did not result in pregnancy. These results show that the hormonal induction of ovulation, associated to temporary weaning for 96 hours, improves the pregnancy rate in beef cows under nutritional stress between 60 and 75 days postpartum, allowing a three-days period of AI. |
publishDate |
2002 |
dc.date.issued.fl_str_mv |
2002-02-20 |
dc.date.accessioned.fl_str_mv |
2022-10-31T15:17:23Z |
dc.date.available.fl_str_mv |
2022-10-31T15:17:23Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://repositorio.ufsm.br/handle/1/26708 |
url |
http://repositorio.ufsm.br/handle/1/26708 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.cnpq.fl_str_mv |
500500000007 |
dc.relation.confidence.fl_str_mv |
600 600 600 600 600 |
dc.relation.authority.fl_str_mv |
39e380be-dcb6-45dc-96d0-ad18ba64f2b3 69cf82ac-918f-4d44-b4ef-73fcb4d1db4a 17767a8a-150b-4ffd-8a94-30d85af116aa 0744e1c2-1c80-4fc1-95b0-9af3cc43289a |
dc.rights.driver.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Centro de Ciências Rurais |
dc.publisher.program.fl_str_mv |
Programa de Pós-Graduação em Medicina Veterinária |
dc.publisher.initials.fl_str_mv |
UFSM |
dc.publisher.country.fl_str_mv |
Brasil |
dc.publisher.department.fl_str_mv |
Medicina Veterinária |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Centro de Ciências Rurais |
dc.source.none.fl_str_mv |
reponame:Biblioteca Digital de Teses e Dissertações do UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Biblioteca Digital de Teses e Dissertações do UFSM |
collection |
Biblioteca Digital de Teses e Dissertações do UFSM |
bitstream.url.fl_str_mv |
http://repositorio.ufsm.br/bitstream/1/26708/1/DIS_PPGMV_2002_BASTOS_GUILHERME.pdf http://repositorio.ufsm.br/bitstream/1/26708/2/license_rdf http://repositorio.ufsm.br/bitstream/1/26708/3/license.txt |
bitstream.checksum.fl_str_mv |
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bitstream.checksumAlgorithm.fl_str_mv |
MD5 MD5 MD5 |
repository.name.fl_str_mv |
Biblioteca Digital de Teses e Dissertações do UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
_version_ |
1801485328140206080 |