Growth Performance, Intestinal Viscosity, Fat Digestibility and Plasma Cholesterol in Broiler Chickens Fed a Rye-containing Diet Without or with Essential Oil Components

Abstract

The present study was conducted to investigate the effects of dietary essential oil components, i.e., thymol, cinnamaldehyde and a commercial blend of essential oil components (CRINA^® Poultry) on growth performance, fat digestibility, intestinal viscosity and plasma cholesterol in female broiler chickens fed on a diet rich in rye. There were 5 dietary treatments: a diet containing corn, a diet with rye, the rye diet with 100 ppm thymol, the rye diet with 100 ppm cinnamaldehyde and the rye diet with 100 ppm CRINA^® Poultry. Each treatment consisted of 3 cages with 5 birds per cage. Birds fed on the supplement-free diet containing rye instead of corn showed a significantly depressed daily weight gain between 1-14 days of age. The rye-induced suppression of weight gain between 1-14 days of age was partially overcome by the inclusion in the diet of cinnamaldehyde, but the effect failed to reach statistical significance. Birds fed on the diets with rye generally ate less than those fed on the corn diet. Cinnamaldehyde tended to increase voluntary feed intake. The water:feed ratio was increased by the feeding of rye, but the supplements had no effect. The viscosity of jejunal and ileal digesta were significantly elevated when the diet contained rye instead of corn, but there was no counteracting effect of the essential oil components. Fecal fat digestibility was significantly lowered in birds fed on the rye diet, but the supplements did not reverse this effect. Thus, it is concluded that cinnamaldehyde may counteract the antinutritional effect of rye, but without a simultaneous effect on intestinal viscosity or fat digestibility. Feeding rye instead of corn did not modulate plasma cholesterol. Cinnamaldehyde produced a significant increase in plasma cholesterol concentration.