Insulin-like growth factor and growth hormone receptor in postpartum lactating beef cows

Pesquisa Agropecuária Brasileira

Augusto Schneider²  Luiz Francisco Machado Pfeifer¹  Lucas Teixeira Hax¹  Giane Regina Paludo¹  Francisco Augusto Burkert Del Pino¹  Nelson José Laurino Dionello¹  Marcio Nunes Corrêa¹ 

[1] ,Universidade Federal de Pelotas Núcleo de Pesquisa, Ensino e Extensão em Pecuária Centro de BiotecnologiaPelotas RS ,Brazil

关键词: Bos indicus;    Bos taurus;    GHR;    IGF-I;    mRNA hepatic expression;    ovulation;    Bos indicus;    Bos taurus;    GHR;    IGF-I;    expressão hepática de mRNA;    ovulação;   

DOI  :  10.1590/S0100-204X2010000800019

来源: SciELO

【 摘 要 】

The objective of this study was to evaluate the plasma concentrations of insulin-like growth factor-I (IGF-I), and the mRNA hepatic expression of IGF-I and of the growth hormone receptors GHR and GHR 1A, in postpartum beef cows. Four Angus and four crossbred (Angus x Nelore) postpartum suckled beef cows were used. Liver and blood samples were collected every 10 days, from calving to 40 days postpartum, for gene expression and for β-hydroxybutyrate and IGF-I assays, respectively. Samples for progesterone assay were collected every other day, from day 10 to 40 postpartum. Three cows ovulated before 40 days postpartum. IGF-I concentration was higher in Angus x Nelore than in Angus cows. There was no difference in the expression of GHR, GHR 1A and IGF-I according to breed or ovulatory status. IGF-I concentrations were higher in crossbred cows, but have not changed according to postpartum ovulatory status. Moreover, changes in postpartum IGF-I concentrations are not associated with changes in liver GHR, GHR 1A and IGF-I mRNA expression in either breed.

【 授权许可】

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