Effect of dietary organic and inorganic selenium on antioxidant status, embryo development, and reproductive performance in hyperovulatory first-parity gilts1

Abstract

This project aimed to determine the effect of Se as inorganic Na-selenite (MSe) or organic Se-yeast (OSe) on antioxidant status, hormonal profile, reproductive performance, and embryo development in first-parity gilts. Forty-nine gilts were allocated to 1 of the 3 dietary treatments starting at first pubertal estrus and lasting up to 30 d after AI: control [CONT: basal diet (Se = 0.2 mg/kg) without added Se; n = 16], MSe (CONT + 0.3 mg/kg of MSe; n = 16), and OSe (CONT + 0.3 mg/kg of OSe; n = 17). Blood was collected from all gilts on the day after each onset of estrus and on d 30 after AI. Blood was also collected daily from d -4 to d +4 of the third onset of estrus (d 0) in 8 CONT, 9 MSe, and 8 OSe cannulated gilts. Gilts had received, after d 14 and 15 of their third estrus, a hormonal challenge to induce super-ovulation. At slaughter, embryos and corpora lutea (CL) were weighed and measured. Blood Se was less (P < 0.01) in CONT than in Se gilts and greater in OSe than in MSe (P < 0.01) from the first estrus until d 30 of gestation. At the same time, blood Se-dependent glutathione peroxidase (GSH-Px) decreased for CONT gilts, whereas it increased for both Se groups. The increase was greater in MSe than in OSe gilts (treatment × time, P = 0.02). Plasma 3,3',5-triiodothyronine and thyroxine concentrations for MSe tended to be less than for OSe gilts (P < 0.06). In cannulated gilts, plasma FSH tended to change among treatments (treatment × time, P = 0.06), and plasma estradiol-17β (E(2)) was less (P = 0.01) for MSe than for OSe. There was no treatment effect on mean litter size or embryonic antioxidant status. The Se content of individual embryos was greater for Se-treated than for CONT gilts (P = 0.03), and Se content of individual embryos and total litter was greater for OSe than for MSe gilts (P < 0.01). The length, weight, and protein content of embryos were greater in OSe than in MSe gilts (P < 0.05). There was no treatment effect on weight, length, Se content, and ferric reducing antioxidant power of CL, but GSH-Px in CL was greater for Se than for CONT gilts (P = 0.02). In summary, the Se status response of gilts to dietary Se was affected by both the quantity and the source of Se dietary supplements. Moreover, the uterine transfer of Se to embryos was improved with OSe as compared with MSe, and this was concomitant with an enhanced development of embryos.

Gene expression of porcine blastocysts from gilts fed organic or inorganic selenium and pyridoxine

“…This was observed in spite of a lack of effect on embryo SeGPX activity (Fortier et al 2012). The metabolic and physiological mechanisms involved in such responses deserve further investigation.…”

Towards amino acid recommendations for specific physiological and patho-physiological states in pigs

“…Then, it is mineralised to selenide and Se phosphate (9)(10)(11) and resynthesised into a seleno-cysteinyl moiety that modulates gene expression and activates Sedependent enzyme, GSH-Px (9,12) . This metabolic control was observed recently in pigs (13) by studying homoeostasis of Se-dependent GSH-Px during the peri-estral period under oxidative pressure (Fig. 1).…”

“…In a recent experiment, the importance of pyridoxine for an adequate flow of organic Se (Se-cysteine) towards the GSHPx system was demonstrated in response to oxidative pressure induced by the peri-estrus period in sows (14) . Indeed, gene expressions of GSH-Px and Se-cysteine oxidase (control of the flow of Se-cysteine to the GSH-Px system) in the Peri-oestral period (d) for days -4, -3, -2, -1, 0, 1, 2 and 3 (adapted from (13) ).…”

Improvement of the Antioxidative Status of Pig Ovaries by Selenopyran Treatment

“…Fortier et al (2012), reported that the GPx in yellow bodies (CL) from ovaries of treated with Se pigs was greater that in the control group. Concerning the other main characteristics of CL including weight, diameter, total number or Se content, authors didn't find the treatment effect (22).…”