Immunoglobulin concentrations in serum and nasal secretions of calves at the onset of pneumonia

Abstract

Immunoglobulin (Ig) concentrations in serurn and in nasal secretions were correlated with pneumonia and diarrhea during the first 12 wk of life of dairy calves. The peak onset of pneumonia occurred between 2 and 4 wk of age when the calves' serum Ig G1, Ig G2 and IgA concentrations were lowest. As IgG2 concentrations increased, fewer calves developed pneumonia. Peak onset of pneumonia was also correlated with the lowest IgG and IgA concentrations in the calves' nasal secretions. Diarrhea often preceded pneumonia.