Effects of Supplemental Lactoferrin on Serum Lactoferrin and IgG Concentrations and Neutrophil Oxidative Metabolism in Holstein Calves

Abstract

Lactoferrin (LF) is an iron-binding protein present in both colostrum and secondary granules of polymorphonuclear neutrophils (PMNs). We hypothesized that supplemental LF enhances neutrophil function in neonatal calves. Newborn calves were assigned to receive colostrum (C), colostrum + LF (CLF, 1 g/kg), or milk replacer + LF (MRLF, 1 g/kg). Serum (LF and IgG) and whole blood (neutrophil isolation) samples were obtained prior to treatment (day 0) and at 24 hours and 9 days of age. Serum IgG concentrations (mean ± SD) in C, CLF, and MRLF calves at 24 hours were 1,911 ± 994 mg/dL, 2,181 ± 625 mg/dL, and 0 mg/ dL, respectively. Serum LF concentrations in C, CLF, and MRLF calves on day 0 were 324 ± 334 ng/mL (range 0-863 ng/mL), 135 ± 158 ng/mL (range 0-429 ng/mL), and 318 ± 337 ng/mL (range 0-964 ng/mL), respectively. LF concentrations in C, CLF, and MRLF calves at 24 hours were significantly higher (P