THE PROPHYLACTIC EFFECT OF VITAMIN-C SUPPLEMENTATION ON BROILER ASCITES INCIDENCE AND PLASMA THYROID-HORMONE CONCENTRATION

In a two-factorial experiment, 420 1-day-old male commercial broiler c hickens were randomly divided and fed a basal diet with or without vit amin C (500 parts/10(6)). Half of the birds within each group receivin g the same kind of feed were fed a T-3 supplemented diet from day 1, i n order to increase the ascites incidence. Weekly body weight and feed intake were measured. Venous blood samples were taken from 10 birds p er group weekly from day 14 on, for haematocrit measurements, blood ga s analysis, measurement of thyroid hormones and lactate/pyruvate ratio s. Ascites mortality was recorded daily. Dietary T-3 significantly inc reased ascites mortality. Adding vitamin C to the feed significantly r educed ascites mortality while it had no effect on performance paramet ers. Plasma thyroid hormone levels were significantly reduced by dieta ry vitamin C administration, but neither haematocrit nor blood gas lev els were influenced.