Effects of maternal peripartum supplementation with Schizochytrium oil on metabolic status, colostrum quality, and neonatal calf performance and immunity in dairy cows

Abstract

The periparturient period in dairy cattle is characterized by significant metabolic stress, often involving a state of negative energy balance, heightened oxidative stress, and systemic inflammation. Supplementation with n-3 PUFA, such as docosahexaenoic acid (DHA), is a strategy employed to mitigate these negative effects due to their recognized anti-inflammatory and immunomodulatory properties. Furthermore, peripartum cow nutrition during this phase may exert a prenatal programming effect on calf immune development, particularly because DHA is efficiently transported across the placenta to the fetus. This study investigated the effects of feeding DHA-rich Schizochytrium oil (SCH) to dairy cows during the peripartum period on peripartum cow health, colostrum quality, and the early immunity and growth of their offspring. Twenty multiparous Holstein cows were randomly assigned to a control group (CON, fed a basal diet) or a SCH group (SCH, fed 150 g/d of SCH, providing 18.9 g of DHA) from 30 d before expected calving until 7 d postpartum. To specifically evaluate the prenatal programming effects, neonatal calves were separated immediately after birth and fed pooled, standardized high-quality colostrum. Cows in the SCH group exhibited significantly enhanced plasma total antioxidant capacity and superoxide dismutase activity by 7 d postpartum compared with the CON group. Correspondingly, levels of the systemic inflammatory marker IL-6 were significantly lower, whereas plasma high-density lipoprotein cholesterol concentrations were significantly higher. Analysis of colostrum showed a pronounced enrichment of DHA, a significant reduction in the n-6/n-3 fatty acid ratio, a decrease in the IL-1β concentration, and a significant reduction in lactose content. Although DHA supplementation of peripartum cows did not significantly affect newborn calf birth weights or structural measurements, SCH calves exhibited significantly reduced serum concentrations of the tumor necrosis factor-α and IL-6 on d 2 postpartum.