Supplementation of lysophospholipids in calf starter: Effects on growth performance, blood metabolites, health, and ruminal ammonia nitrogen concentration

The aim of the current study was to evaluate the effects of a commercial mixture of Lysophospholipids (LPL) in calf starter on performance, blood metabolites, antioxidant capacity, liver enzymes concentration, and health status of pre-weaning dairy calves. Forty-eight newborn female Holstein calves (37.5 +/- 2.9 kg of body weight) were randomly assigned to four treatments (12 replicates), which included the control (CON, without additive) and a commercial blend of LPL at 0.5, 1, and 1.5 g/kg of starter feed. The body weight of the calves was measured using a digital scale on days 15, 30, 45, and d 63 of the experimental period to calculate the average daily gain (ADG). The individual starter intake and fecal score were measured daily. Blood samples were collected at 30 and 63 days, while fecal samples were collected for four consecutive days after weaning to measure nutrient digestibility. The treatments did not significantly afffect the total dry matter and starter intake. However, the supplementation of LPL resulted in an increase in the ADG and improved feed efficiency (FE, from1-63 d) compared to the CON group. The addition of LPL did not have any significant impact on the apparent digestibility of dry matter (DM), and organic matter (OM). Eether extract (EE) digestibility tended to increase with the addition of LPL. Calves that received starter feed containing 0.5 g/kg of LPL had higher superoxide dismutase activity at 30 d of age compared to the intake.CON group. Additionally, the average fecal score significantly decreased in calves fed 0.5 and 1.5 g/kg LPL compared with the CON group. These findings suggest that the inclusion of LPL at an average dose of 1 g/kg of calf starter can improve the performance of pre-weaning Holstein dairy calves.