Insulin-stimulating diets during the weaning-to-estrus interval do not improve fetal and placental development and uniformity in high-prolific multiparous sows

Abstract

Piglet birth weight and litter uniformity are important for piglet survival. Insulin-stimulating sow diets before mating may improve subsequent piglet birth weights and litter uniformity, but the physiological mechanisms involved are not clear. This study evaluated effects of different levels of insulin-stimulating feed components (dextrose plus starch; fed twice daily) during the weaningto-estrus interval (WEI) on plasma insulin and IGF-1 concentrations, and on follicle development and subsequent luteal, fetal and placental development and uniformity at days 42 to 43 of pregnancy. During WEI, multiparous sows were isocalorically fed diets supplemented with 375 g/day dextrose plus 375 g/day corn starch (INS-H), with 172 g/day dextrose plus 172 g/day corn starch and 144 g/day animal fat (INS-L), or with 263 g/day animal fat (CON). Jugular vein catheters were inserted through the ear vein at 1.5 days before weaning to asses plasma insulin and IGF-1 concentrations. After estrus, all sows received a standard gestation diet until slaughter at days 42 to 43 of pregnancy. The dextrose plus starch-diets enhanced the postprandial insulin response in a dose-dependent manner (e.g. at day 2 insulin area under the curve was 4516 mU/444 min for CON, 8197 mU/444 min for INS-L and 10 894 mU/444 min for INS-H; s.e.m. 5 694; P , 0.001), but did not affect plasma IGF-1 concentrations during the first 3 days of WEI. Follicle development and subsequent luteal, fetal and placental development and uniformity were not affected by the dietary treatments, nor related to plasma insulin and IGF-1 concentrations during WEI. Pre-weaning plasma insulin and IGF-1 concentrations were negatively related to sow body condition loss during lactation, but were not related to subsequent reproduction characteristics. This study shows that dietary dextrose plus starch are effective in stimulating insulin secretion (both postprandial peak and long-term concentration), but not IGF-1 secretion during the first 3 days after weaning in multiparous sows. The extreme insulin-stimulating diets during WEI did, however, not improve follicle development, or subsequent development and uniformity of fetuses and placentas in these high-prolific sows (27.0 6 0.6 ovulations; 18.6 6 0.6 vital fetuses).

Effects of a high carbohydrate diet and arginine supplementation during the rearing period of gilts on osteochondrosis prevalence at slaughter

“…The associations of insulin and IGF-1 responses between treatments are confirmed by associations found between insulin and IGF-1 in other studies (van den Brand et al, 2001;Wientjes et al, 2013;and reviewed by Thissen et al (2004)). However, the same studies report that dietary treatments did not significantly affect IGF-1 levels.…”

“…These higher insulin and glucose levels in the carbohydrate treatment coincide with higher IGF-1 levels in gilts receiving the C À treatment. Previous experiments from literature with insulin stimulating diets (high carbohydrates) report similar results for glucose and insulin on the short term (van den Brand et al, 1998(van den Brand et al, , 2000Wientjes et al, 2012Wientjes et al, , 2013. In comparison to the C þ treatment, the C À treatment had less glucogenic compounds in the feed and the increase in glucose on the longer term for gilts in the C À treatment may reflect glycogenolysis to increase glucose levels for the citric acid cycle (van Knegsel et al, 2005).…”

“…The carbohydrate level consisted of a diet with 12.5% cornstarch and 12.5% dextrose added to the commercial basal diet (high carbohydrate diet; Cþ) versus a diet in which the cornstarch and dextrose was replaced with an isocaloric (based on MJ NE/kg) 8.9% soya bean oil (low carbohydrate diet; CÀ ). This contrast of carbohydrate level was determined from previous experiments as the largest possible contrast conceivable in commercial diets in terms of food uptake and digestion (Wientjes et al, 2013). Arginine (L-arginine, Daesang Corp., Seoul, South Korea) supplementation consisted of 0.8% arginine added to the commercial basal diet (Aþ) versus 1.64% alanine (L-alanine, Omya Hamburg GmbH, Hamburg, Germany) supplemented to the basal diet as the isonitrogenous control (AÀ ) as described by others (He et al, 2011;Shan et al, 2012;Zheng et al, 2013).…”

“…However, insulin and IGF-1 can increase growth and body weight (BW) gain that in turn can increase OC prevalence (de Koning et al, 2013). Carbohydrate rich diets affect metabolic parameters such as glucose and insulin and is correlated with IGF-1 in pigs (Wientjes et al, 2012(Wientjes et al, , 2013. It may be possible that both a carbohydrate rich diet and supplementation with arginine affect the prevalence of OC, where arginine supplementation could aid reparative responses and reduce OC prevalence, and carbohydrates may aid reparative responses reducing OC prevalence or increase growth and thereby increasing OC prevalence.…”

Consequences of different dietary energy sources during follicular development on subsequent fertility of cyclic gilts

“…Our results also showed insulin effects on the ovary, improving follicle growth and subsequent ovulation rate. In contrast, the recent study of Wientjes et al (2013) reported that insulin-stimulating diets fed to hyperprolific multiparous sows during the weaning-to-estus interval did not improve follicle development and uniformity of fetuses and placentas, which emphasizes the metabolic differences between the cyclic gilt and the lactating and weaned sows experimental models.…”