Associations of insulin resistance later in lactation on fertility of dairy cows

Factors that interfere with oocyte quality for in vitro production of cattle embryos: effects of different developmental & reproductive stages

“…These findings corroborate previous studies showing that lactating cows at later lactation are prone to insulin resistance, which clearly seem to lower oocyte viability during IVP procedures. Baruselli et al, 2016.…”

“…The level of energy intake for example, can affect circulating levels of insulin and IGF-1 (reviewed by Sartori et al, 2016). As a result, excessive increase in insulin concentration in blood, mainly in dairy cows later in lactation, are negatively associated with oocyte quality (reviewed by Baruselli et al, 2016). Exposure to heat stress is widely known to be deleterious to oocyte competence in Bos taurus cattle (Ferreira et al, 2011;Ferreira et al, 2016).…”

Effects of concentrate type and chromium propionate on insulin sensitivity, productive and reproductive parameters of lactating dairy cows consuming excessive energy

“…Insulin resistance has been shown to impair oocyte fertility (Adamiak et al, 2005;Leiva et al, 2015), and such outcome can be attributed to reduced mRNA concentrations of IGF-I binding proteins as well as insulin receptors within small follicles (Baruselli et al, 2016). The lack of treatment differences for reproductive variables herein indicate that both concentrate type and Cr-propionate supplementation did not impact oocyte production and Table 5 Milk yield of lactating dairy cows consuming excessive energy, and receiving in a 2 × 2 factorial arrangement design: (1) concentrate based on ground corn (CRN; n = 13) or citrus pulp (PLP; n = 13), and (2) supplemented (n = 14) or not (n = 12) with 2.5 g/day of Cr-propionate Milk production was recorded daily and milk samples were collected weekly from each cow, which was analyzed using infrared spectrometry (method 972.16; AOAC, 1999) by a commercial laboratory (Clínica do Leite).…”

“…Feeding the citrus pulp-based concentrate did not improve any of the aforementioned variables, whereas Cr-propionate supplementation only enhanced insulin sensitivity parameters in cows receiving a corn-based concentrate during a GTT. Given the negative relationship among excessive energy intake, insulin sensitivity parameters and productive responses in lactating cows (LeBlanc, 2010;Baruselli et al, 2016), research is still warranted to develop nutritional strategies that mitigate insulin resistance and optimize performance and welfare in dairy cattle. Table 6 Oocyte collection and in vitro embryo production from lactating dairy cows consuming excessive energy and receiving in a 2 × 2 factorial arrangement design: (1) concentrate based on ground corn (CRN; n = 13) or citrus pulp (PLP; n = 13), and (2) supplemented (n = 14) or not (n = 12) with 2.5 g/day of Cr-propionate Follicle aspiration was performed on days −1, 62 and 162 via transvaginal ovum pick-up, processed and maturated for in vitro fertilization and fertilized with semen from the same sire (Bilby et al, 2006).…”

“…This syndrome, characterized by persistent hyperglycemia despite increased insulin secretion, has been shown to impair welfare and reproductive parameters of dairy cattle (Adamiak et al, 2005;Leiva et al, 2015;Baruselli et al, 2016). Given that excessive energy intake is common and often inevitable among late-lactating and non-lactating cows in commercial dairies (Van Saun and Sniffen, 1996), nutritional strategies that mitigate insulin resistance are warranted to optimize productivity and welfare of dairy cattle.…”