Experiment was carried out to test the influence of mixed bovine colostrum thermisation on immunoglobulin intestinal absorption in newborn lambs. Thirty-three newborn lambs were alloted to three treatments: free maternal suckling or three meals of pooled bovine colostrum (30/kg BW), given 0.5, 3.5 and 6.5 h after birth or three meals of the same but previously heated bovine colostrum. Gentle thermal treatment (62°C for 1 min.) was used in order to preserve immunoglobulin biological activity. Immunoglobulin G levels determined in blood samples collected 3.5, 6.5, 9.5 and 12.5 h after birth were satisfactory but lower in animals receiving bovine colostrum. Thermisation resulted in decreased microbial contamination but did not affect Ig plasmatic levels. In the absence of pathogenic germs, heating colostrum is not necessary to enable an efficient intestinal transfer of immunoglobulin.