EFFECT OF THREONINE ON THE BEHAVIORAL-DEVELOPMENT OF THE RAT

Rats received different levels of threonine (Thr), one, 1.7, and four times the normal dietary intake, from conception to adulthood. The mot hers were fed the experimental diets before and during pregnancy. Thei r offspring received a daily oral load of Thr or placebo until weaning . Thereafter, the juveniles were fed the same diet as their mothers. M orphologic development, ingestive behaviour, homing, and locomotion we re observed before weaning. Exploration and spontaneous alternation we re studied thereafter. Animals exposed during gestation to 1.7 times t he normal Thr intake consumed more food during the test of independent ingestion. Grooming showed inconsistent variations between days 12 an d 29 in pups fed 1.7 times the normal Thr intake. Rats performed equal ly well on the other behavioural tasks independently of the dietary tr eatment. We conclude that Thr intake as much as four times higher than the levels found in normal diets does not impair the behavioural onto genesis of the rat.