Resumo

HERNANDEZ-CERON, Joel  e  GUTIERREZ-AGUILAR, C. Guillermo. Recombinant bovine somatotropin and reproduction in cattle, sheep and goat. Agrociencia [online]. 2013, vol.47, n.1, pp.35-45. ISSN 2521-9766.

In cows, recombinant bovine somatotropin (rbST) is used to increase milk production. The rbST increases serum concentrations of the insulin-like growth factor I (IGF-I) and both hormones regulate physiological processes to increase lactopoiesis. In addition to its effects on lactation, somatotropin and IGF-I favor maturation of the oocyte, the fertilization rate, early embryo development, function of the corpus luteum, and maternal recognition of pregnancy. Administering rbST has been evaluated in different physiological periods to improve the reproductive performance in ruminants. In subfertile dairy cows, administering rbST at the time of insemination increases conception rate (CR). In first-service cows, the repeated injection of rbST every 14 d, integrated into the fixed-time insemination programs, also improves CR. In sheep and goats, rbST benefits the maturation of oocytes, early embryo development and improves prolificacy. Pero, this hormone is not integrated into reproductive management programs. The results described in this essay offer solid bases to consider the incorporation of rbST use to cattle, sheep and goat reproductive programs.

Palavras-chave : rbST; fertility; cows; sheep; goats.

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