Nutritional status of donor cows: insulin related strategies to enhance embryo development

Ponsart, CGamarra, GLacaze, SPonter, A. A

Nutritional and metabolic status of domestic ruminant females is linked with reproductive success. Diet can influence ovarian activity via effects at various levels of the hypothalamus-pituitary-ovarian axis. Changes in the plane of nutrition can affect follicular growth by inducing changes in plasma metabolites and metabolic hormones, such as insulin and IGF1. This paper will review different results from in vivo and in vitro feeding approaches describing a programmed sequence in circulating insulin concentrations. The stimulatory effect of insulin and IGF1 on follicle growth has been previously demonstrated, especially on small follicle growth prior to superovulation. Thus, in vivo feeding strategies have been recently tested to enhance embryo development. It has been shown that the interaction between the gonadotropin content of the superstimulatory preparation with the nutritional program of the donor cow needs to be considered when aiming to optimize the success of ovarian superstimulatory protocols. Moreover, some practical feeding strategies such as short term dietary propylene glycol could improve in vitro embryo production in superovulated growth-restricted heifers. To conclude, different diets or dietary supplements may improve fertility and embryo quality by inducing a programmed sequence in circulating insulin concentrations (AU)

1. metabolic status
2. in vitro
3. bovine
4. in vivo
5. feeding