139 Ghrelin Improves the Development of Bovine Preimplantation Embryos in Vitro

Seasonal and parity effects on ghrelin levels throughout the estrous cycle in dairy cows

“…Another study found greater blastocyst-formation rate and hatching in oocytes treated with ghrelin (Dovolou et al, 2014b). This positive effect of ghrelin on animal fertility was demonstrated in other farm animals as well in a different range of concentrations spectrum (Young et al, 2001;Zhang et al, 2007;Dashtizad et al, 2010;Wang et al, 2013). These studies, combined with our results suggest that reduced ghrelin levels during the summer lead to impaired oocytes and embryos development and quality, and elevated ghrelin levels might contribute to the improved fertility in dairy cows during the winter.…”

“…In addition to appetite control regulation and GH secretion, ghrelin takes part in many other physiological processes, including stress (Chuang et al, 2011;Diz-Chaves, 2011), sleep and memory (Steiger et al, 2011), regulating insulin secretion (Broglio et al, 2001) and glucose uptake (Gershon and Vale, 2014 Another major physiological process affected by ghrelin is fertility (Rak-Mardyla, 2013). Previous studies in many farm animals demonstrated that ghrelin actions on reproduction performances are within a concentration spectrum (Young et al, 2001;Zhang et al, 2007;Du et al, 2010;Dashtizad et al, 2010;Wang et al, 2013). However, less is known of ghrelin and seasonal effect in the cow, especially the dairy cow, in which a major fertility issue has emerged in conjunction with selection for increased milk production.…”