Liver ornithine decarboxylase activity in suckling pigs after short term maternal deprivation

Two female piglets from each of 23 litters were used to determine the effect of short term maternal deprivation on liver ornithine decarboxylase (ODC) activity at 3, 10, 17, 24, and 31 days of age. Data on body weight, liver weight and plasma glucose, catecholamine and growth hormone concentrations were also recorded. Liver ODC activity declined (P less than .01) with increasing age and was reduced (P less than .0001) at each age compared with control values after maternal deprivation for 16 h. Liver weight and plasma glucose were reduced (P less than .01) by maternal deprivation, while plasma catecholamines were unchanged and plasma growth hormone tended to be reduced, although the difference between means for deprived and control animals was not significant (P greater than .05). The design of the experiment did not permit separation of the relative contributions of sensory deprivation versus food deprivation of piglets in inducing the decline in liver ODC activity. The results indicate that maternal deprivation causes a marked decrease in liver ODC activity in neonatal swine as shown previously in neonatal rats (Schanberg et al., 1984).