EFFECT OF TIME ON NEONATAL IMMUNE-RESPONSE TO DIETARY SELENIUM AND FAT

The effect of dietary selenium (0.03 mg/kg and 0.31 mg/kg), and fat (5 % and 20% corn oil) on antibody formation in the neonatal rat was stud ied at two different time periods using four diets. The latter were fe d to dams throughout pregnancy and lactation and to their pups startin g at day 18. A week later, pups received intraperitoneal injections of the test antigen, fluorescein-bovine serum albumin in complete Freund 's adjuvant (150 mug per 30 g body wt.). On days 7 or 9 post-injection , the pups were sacrificed. The antibody titer, as determined by the q uenching of fluorescein by the test sera, and by ELISA, almost doubled from day 7 to day 9 (p < 0.05). There was no significant difference i n antibody titers between dietary groups except at day 9 post-injectio n. Using ELISA, pairwise comparisons indicated that addition of 0.3 mg /kg Se to high fat diet was associated with low antibody titer (p < 0. 05).