THE INFLUENCE OF THE SOW'S ADRENAL ACTIVITY ON THE ABILITY OF THE PIGLET TO ABSORB IgG FROM COLOSTRUM

Abstract

To study modifications in adrenal activity, 18 pregnant Yorkshire sows were infused intravenously with either ACTH, metyrapone or saline between days 104 and 114 postbreeding. During this time the sows were bled twice daily. At birth the piglets were force fed pooled bovine colostrum until 6 h of life and bled at birth, 6 h, 1, 2, 4, 8, 12, 16 and 21 days of age. Cortisol, corticosterone, and 11-deoxycortisol were measured in sow serum and the concentrations of bovine and porcine immunoglobulin G (IgG) were measured in piglet serum. ACTH significantly increased the levels of cortisol, corticosterone and 11-deoxycortisol in sows. Metyrapone did not produce a significant reduction in the levels of cortisol or corticosterone but the concentration of 11-deoxycortisol was significantly elevated in comparison to the controls. Piglets from sows treated with ACTH (A pigs) had significantly more bovine IgG than controls (C pigs) at 6 h of life, and maintained higher levels at the other sampling times. Piglets from sows treated with metyrapone (M pigs) had significant increased serum concentrations of bovine IgG from 6 h to 21 days. The concentration of bovine IgG at 6 h was about 71% higher in M pigs than in the C pigs. At birth, M pigs were heavier than A pigs, and C pigs were the lightest of the three groups. Key words: Piglets corticosteroids, IgG, absorption, colostrum