Ensuring a newborn calf receives sufficient IgG, as quickly as possible, is central to successful passive immunity, yet not all colostrum replacers perform equally. This study evaluated IgG absorption in calves fed a replacer enriched to match natural colostrum’s antibody concentration, monitoring serum IgG in the hours after feeding to confirm effectiveness. For producers who depend on replacer due to limited donor colostrum or challenging calving schedules, these results speak directly to a key question: can a scientifically formulated replacer support calves as reliably as high-quality maternal colostrum?
"Effects of enriching IgG concentration in low- and medium-quality colostrum with colostrum replacer on IgG absorption in newborn Holstein calves" — A.J. Lopez, J. Echeverry-Munera, H. McCarthy, A.C. Welboren, A. Pineda, M. Nagorske, D.L. Renaud, M.A. Steele. J Dairy Sci. 2023 May;106(8):3680-3691.