The Effects of Prenatal Supplementation with β-Hydroxy-β-Methylbutyrate and/or Alpha-Ketoglutaric Acid on the Development and Maturation of Mink Intestines Are Dependent on the Number of Pregnancies and the Sex of the Offspring

SIMPLE SUMMARY: The American mink has a unique and complex biology, and farmed mink can produce multiple litters. Reproductive success depends on optimal housing, nutrition, body condition and genetic selection. Nutrition during pregnancy affects fetal and offspring development. Therefore, feed supplements must be introduced with caution, especially on high productivity farms, where reproductive efficiency depends on optimal maternal nutrition and maintaining the best possible animal health status. The current study aimed to investigate the structure and maturation of the small intestine in the offspring of primiparous and multiparous mink supplemented with β-hydroxy-β-methylbutyrate and/or alpha-ketoglutaric acid during gestation. Prenatal supplementation induced long-term effects on intestinal development in offspring which were dependent on parity and offspring gender. Intestinal absorption, peristalsis and secretion were affected by prenatal supplementation, as evidenced by the accompanying structural changes. The findings presented here have important nutritional implications, not only for mink breeding but for production overall. The possible effects of the interactions between parity, offspring gender and dietary supplements should be taken into consideration in terms of feeding practice and supplementation plans for the breeding of animals. Further studies are necessary to elucidate possible epigenetic effects of gestational supplementation on the generations of offspring that follow. ABSTRACT: Prenatal and postnatal supplementation with β-hydroxy-β-methylbutyrate (HMB) and alpha-ketoglutaric acid (AKG) affects the development and maturation of offspring. Both substances have the potential to stimulate cell metabolism via different routes. However, parity affects development and may alter the effects of dietary supplementation. This study aimed to evaluate the effect of gestational supplementation with HMB and/or AKG to primiparous and multiparous minks on the structure and maturation of the offspring’s small intestine. Primiparous and multiparous American minks (Neovison vison), of the standard dark brown type, were supplemented daily with HMB (0.02 g/kg b.w.) and/or AKG (0.4 g/kg b.w.) during gestation (n = 7 for each treatment). Supplementation stopped when the minks gave birth. Intestine samples were collected from 8-month-old male and female offspring during autopsy and histology and histomorphometry analysis was conducted (LAEC approval no 64/2015). Gestational supplementation had a long-term effect, improving the structure of the offspring’s intestine toward facilitating absorption and passage of intestinal contents. AKG supplementation affected intestinal absorption (enterocytes, villi and absorptive surface), and HMB affected intestinal peristalsis and secretion (crypts and Goblet cells). These effects were strongly dependent on parity and offspring gender. Present findings have important nutritional implications and should be considered in feeding practices and supplementation plans in animal reproduction.