[Necessary care of newborn lambs using ovine colostrum. 2. Duration of administration].

Sheep colostrum, pooled from 0-12 h milkings, was fed to 38 newborn lambs for either 6, 12, 18 or 24 hrs after birth. The influence of the duration of feeding periods on the transintestinal passage of immunoglobulins, the growth performance, the loss rate and the onset of immunoglobulin synthesis were investigated by monitoring the serum concentrations of IgG1, IgG2, IgM and IgA during months 1 through 9 of life. Feeding of 3 portions of 100 ml at 2 h intervals resulted in lower serum levels of Ig's than the extension of the feeding to 12 x 100 ml every second hour. There was, however, no difference in the onset of endogenous Ig production between both groups. Growth performance and the loss rate were also identical.