The Serum biochemical parameters, and liver enzyme activity of ewes on the day of parturition and of their newborn lambs in response to selenium supplementation during late pregnancy

The effect of dietary Selenium supplementation during late pregnancy on biochemical parameter and enzymes activity of ewes on the day of lambing and of their newborn lambs.

Abstract

This study was designed to evaluate the influence of dietary supplementation with selenium-enriched yeast (SeY) during late gestation on critical biochemical parameters, liver enzyme activity, and thyroid hormone status in periparturient ewes and their newborn lambs, hypothesising that SeY would mitigate the metabolic and oxidative stress characteristic of this period. Eighteen pregnant ewes (n=18) were equally and randomly allocated to one of three daily supplementation groups: a Control group (C) receiving 0 mg Se/kg Dry Matter (DM), a low-dose SeY group (T1) receiving 1.0 mg Se/kg DM, and a high-dose SeY group (T2) receiving 2.0 mg Se/kg DM. Blood samples were collected from the ewes on the day of parturition and from their newborn lambs during the first week of age. Serum was subsequently analysed for concentrations of total protein, urea, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), creatinine, and the activity of the hepatic enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The results demonstrated a significant, dose-dependent metabolic improvement in supplemented ewes: serum total protein and urea concentrations were notably higher in both T1 and T2 groups compared to the Control group (P < 0.05), indicating enhanced protein utilization. Conversely, markers of potential stress or impaired lipid metabolism specifically total cholesterol, LDL, and creatinine were significantly higher in Control ewes than in both SeY-supplemented groups. Furthermore, the elevated activity of AST and ALT enzymes recorded in Control ewes was significantly reduced in the T1 and T2 groups, suggesting effective hepatoprotection conferred by SeY. Crucially, these maternal benefits were conferred to the offspring: lambs born to Control ewes exhibited higher concentrations of cholesterol, HDL, LDL, and creatinine, along with significantly greater AST and ALT enzyme activities, compared to lambs from SeY-supplemented ewes. In conclusion, dietary SeY supplementation during late pregnant ewes successfully regulated maternal protein and lipid metabolism, reduced indicators of hepatic stress in the dam, and effectively transferred protective effects, resulting in improved metabolic and hepatic health profiles in newborn lambs. These results confirm the clinical value of SeY during late gestation to optimize the peripartum health trajectory for both the ewes and their offspring.