LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION

Detalhes bibliográficos
Autor(a) principal: Cardoso, Daniel
Data de Publicação: 2009
Outros Autores: Ferreira, Guerra Fábio, Nogueira, Guilherme Paula
Tipo de documento: Artigo
Idioma: por
Título da fonte: Ciência animal brasileira (Online)
Texto Completo: https://revistas.ufg.br/vet/article/view/3788
Resumo: The aim was to evaluate the LH secretion in B. indicus heifers, on the presence or absence of gonadal steroid, generating information about the mechanisms evolved on sexual maturation in Nellore heifers. LH and progesterone concentration were quantified by RIA. First ovulation was determined by plasma progesterone concentration (>1 ng/ml). Greater mean LH concentrations was observed in ovariectomized (OVX; P?0.05) compared to intact heifers (INT). Mean LH concentration increased (P?0.05) during the sexual maturation, in both intact and ovariectomized heifers. The number of peaks was higher (P?0.05) in ovariectomized heifer. The results suggest decrease in estradiol hypothalamus negative feedback during Nellore heifer’s sexual maturation. It was possible to conclude that in pre-pubertal Nellore heifers the increase on positive gonadal steroids feedback was necessary to increase LH secretion before first ovulation.KEY WORDS: Cattle, endocrinology, hypothalamus, puberty, steroids.
id UFG-7_26148bd14d1797d2dddb92dc511eebb4
oai_identifier_str oai:ojs.revistas.ufg.br:article/3788
network_acronym_str UFG-7
network_name_str Ciência animal brasileira (Online)
repository_id_str
spelling LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATIONCONCENTRAÇÃO DE LH EM NOVILHAS DA RAÇA NELORE DA DESMAMA À PRIMEIRA OVULAÇÃOAnimal reproductionReprodução AnimalThe aim was to evaluate the LH secretion in B. indicus heifers, on the presence or absence of gonadal steroid, generating information about the mechanisms evolved on sexual maturation in Nellore heifers. LH and progesterone concentration were quantified by RIA. First ovulation was determined by plasma progesterone concentration (>1 ng/ml). Greater mean LH concentrations was observed in ovariectomized (OVX; P?0.05) compared to intact heifers (INT). Mean LH concentration increased (P?0.05) during the sexual maturation, in both intact and ovariectomized heifers. The number of peaks was higher (P?0.05) in ovariectomized heifer. The results suggest decrease in estradiol hypothalamus negative feedback during Nellore heifer’s sexual maturation. It was possible to conclude that in pre-pubertal Nellore heifers the increase on positive gonadal steroids feedback was necessary to increase LH secretion before first ovulation.KEY WORDS: Cattle, endocrinology, hypothalamus, puberty, steroids.O presente trabalho teve por objetivo investigar a variação na secreção de LH na presença ou não de esteroides gonadais e, dessa forma, gerar informações sobre os mecanismos envolvidos na maturação sexual de novilhas da raça Nelore. Quantificou-se a concentração de LH e progesterona por radioimunoensaio. A primeira ovulação foi determinada pela concentração plasmática de progesterona (>1 ng/ml). As novilhas ovariectomizadas (OVX) apresentaram maior concentração basal de LH (P?0,05) que as novilhas inteiras (INT). Houve uma concentração de LH durante a maturação sexual, tanto nas novilhas INT quanto nas OVX. O número de picos de secreção de LH foi maior (P?0,05) nas novilhas OVX. Os resultados indicam uma diminuição da sensibilidade do hipotálamo aos esteroides gonadais durante o processo de maturação sexual nas novilhas da raça Nelore. Conclui-se que, em novilhas pré-púberes da raça Nelore, o desenvolvimento da retroalimentação positiva aos esteroides gonadais no hipotálamo foi importante para aumentar a secreção de LH antes da primeira ovulação.PALAVRAS-CHAVES: Bovinos, endocrinologia, esteroides, hipotálamo, puberdade.Universidade Federal de Goiás2009-12-20info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionResearchAvaliado por paresPesquisa Científicaapplication/pdftext/htmlhttps://revistas.ufg.br/vet/article/view/378810.5216/cab.v10i4.3788Brazilian Animal Science/ Ciência Animal Brasileira; Vol. 10 No. 4 (2009); 1277-1284Ciência Animal Brasileira / Brazilian Animal Science; v. 10 n. 4 (2009); 1277-12841809-68911518-2797reponame:Ciência animal brasileira (Online)instname:Universidade Federal de Goiás (UFG)instacron:UFGporhttps://revistas.ufg.br/vet/article/view/3788/5950https://revistas.ufg.br/vet/article/view/3788/6042Cardoso, DanielFerreira, Guerra FábioNogueira, Guilherme Paulainfo:eu-repo/semantics/openAccess2009-12-20T12:07:51Zoai:ojs.revistas.ufg.br:article/3788Revistahttps://revistas.ufg.br/vetPUBhttps://revistas.ufg.br/vet/oai||revistacab@gmail.com1809-68911518-2797opendoar:2024-05-21T19:55:10.624616Ciência animal brasileira (Online) - Universidade Federal de Goiás (UFG)true
dc.title.none.fl_str_mv LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
CONCENTRAÇÃO DE LH EM NOVILHAS DA RAÇA NELORE DA DESMAMA À PRIMEIRA OVULAÇÃO
title LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
spellingShingle LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
Cardoso, Daniel
Animal reproduction
Reprodução Animal
title_short LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
title_full LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
title_fullStr LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
title_full_unstemmed LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
title_sort LUTEINIZING HORMONE SECRETION IN NELLORE HEIFER’S AFTER WEANING TO FIRST OVULATION
author Cardoso, Daniel
author_facet Cardoso, Daniel
Ferreira, Guerra Fábio
Nogueira, Guilherme Paula
author_role author
author2 Ferreira, Guerra Fábio
Nogueira, Guilherme Paula
author2_role author
author
dc.contributor.author.fl_str_mv Cardoso, Daniel
Ferreira, Guerra Fábio
Nogueira, Guilherme Paula
dc.subject.por.fl_str_mv Animal reproduction
Reprodução Animal
topic Animal reproduction
Reprodução Animal
description The aim was to evaluate the LH secretion in B. indicus heifers, on the presence or absence of gonadal steroid, generating information about the mechanisms evolved on sexual maturation in Nellore heifers. LH and progesterone concentration were quantified by RIA. First ovulation was determined by plasma progesterone concentration (>1 ng/ml). Greater mean LH concentrations was observed in ovariectomized (OVX; P?0.05) compared to intact heifers (INT). Mean LH concentration increased (P?0.05) during the sexual maturation, in both intact and ovariectomized heifers. The number of peaks was higher (P?0.05) in ovariectomized heifer. The results suggest decrease in estradiol hypothalamus negative feedback during Nellore heifer’s sexual maturation. It was possible to conclude that in pre-pubertal Nellore heifers the increase on positive gonadal steroids feedback was necessary to increase LH secretion before first ovulation.KEY WORDS: Cattle, endocrinology, hypothalamus, puberty, steroids.
publishDate 2009
dc.date.none.fl_str_mv 2009-12-20
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Research
Avaliado por pares
Pesquisa Científica
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv https://revistas.ufg.br/vet/article/view/3788
10.5216/cab.v10i4.3788
url https://revistas.ufg.br/vet/article/view/3788
identifier_str_mv 10.5216/cab.v10i4.3788
dc.language.iso.fl_str_mv por
language por
dc.relation.none.fl_str_mv https://revistas.ufg.br/vet/article/view/3788/5950
https://revistas.ufg.br/vet/article/view/3788/6042
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
text/html
dc.publisher.none.fl_str_mv Universidade Federal de Goiás
publisher.none.fl_str_mv Universidade Federal de Goiás
dc.source.none.fl_str_mv Brazilian Animal Science/ Ciência Animal Brasileira; Vol. 10 No. 4 (2009); 1277-1284
Ciência Animal Brasileira / Brazilian Animal Science; v. 10 n. 4 (2009); 1277-1284
1809-6891
1518-2797
reponame:Ciência animal brasileira (Online)
instname:Universidade Federal de Goiás (UFG)
instacron:UFG
instname_str Universidade Federal de Goiás (UFG)
instacron_str UFG
institution UFG
reponame_str Ciência animal brasileira (Online)
collection Ciência animal brasileira (Online)
repository.name.fl_str_mv Ciência animal brasileira (Online) - Universidade Federal de Goiás (UFG)
repository.mail.fl_str_mv ||revistacab@gmail.com
_version_ 1799874784538918912

Registros relacionados