Supplementation with Lentinan Improves the Colostrum Quality of Holstein Dairy Cows and the Immunity and Antioxidant Capacity of Newborn Calves

The aim of this study was to evaluate the effects of lentinan (LNT) on the quality of colostrum produced by perinatal dairy cows and the health status of their newborn calves. A total of 40 expectant Holstein cows, matched for parity and expected date of delivery, were selected and randomly divided into four groups: a control group fed a total mixed diet (TMR); a low LNT group (10 g/d, LLNT); a medium LNT group (20 g/d, MLNT); and a high LNT group (40 g/d, HLNT). The study commenced 21 days prior to parturition and continued for three weeks. Colostrum was collected from the cows immediately after delivery and subsequently fed to the newborn calves. The results indicated that colostrum milk protein production and IgG production in the MLNT group were significantly increased (<i>p</i> < 0.05). Following colostrum gavage, serum SOD and IgG in both the MLNT and HLNT groups showed significant increases (<i>p</i> < 0.05), while MDA and IL-1β levels were significantly decreased (<i>p</i> < 0.05). Moreover, calves in the MLNT and HLNT groups experienced lower incidences of diarrhea, pneumonia, and overall morbidity compared to those in the control group. In conclusion, LNT enhanced the quality of colostrum in perinatal cows and contributed to the health of newborn calves through colostrum. This study offers new research avenues for improving the health of newborn calves and provides a theoretical foundation for the development of LNT as a novel feed additive.