Effects of Feeding Xylose on the Growth of Broilers and Nutrient Digestibility as well as Absorption of Xylose in the Portal-drained Viscera

Abstract

Two experiments were conducted to examine the effects of dietary inclusion of xylose on growth performance, nutrient digestibility and xylose absorption in the portal-drained viscera of broiler chicks. In Exp. 1, ninety male 14 day-old broilers were used to study the effects of different inclusion levels (0, 5, 10, 20 and 40%) of D-xylose in the semi-purified diets on the growth and nutrient digestibility of broilers. In Exp. 2, One hundred and eight male broilers, fed by precision feeding at 22 day-old, were used to investigate the absorption and transportation of dietary xylose in the portal-drained viscera of broiler. The results of Exp. 1 indicated that the growth of broilers was gradually decreased as the xylose level increased (p<0.01). With the xylose supplementation increased, the moisture in broiler excreta was gradually elevated (p<0.01), AME and the digestibilities of crude protein and ether extract were significantly reduced and the digestibilities of xylose and arabinose were also decreased (p<0.01). The results of Exp. 2 showed that the concentrations of ribose, xylose and galactose in serum were significantly influenced by different dietary levels of xylose (p<0.01), but there's no apparent difference among rhamnose, glucose and arabinose (p>0.05). The xylose concentration in serum was highest in Vena Cava, middle in Portal Vein and lowest in Ulnar Vein within 6 h after precision feeding. And then the xylose concentration in Portal Vein and Ulnar Vein were higher than that of Vena Cava. The concentration of ribose, xylose and galactose in serum were also significantly changed with time prolongation (p<0.01). The concentration of xylose in serum was highest in the 40% xylose treatment, middle in the 20% xylose group and lowest in the control group. The glycogen contents in liver and muscle were linearly decreased as the level of xylose increased (p<0.01). The higher the dietary level of xylose was, the lower digestibility of dietary xylose was (p<0.10). 40% xylose markedly decreased the digestibility of dietary glucose (p<0.01). In conclusion, high levels of xylose in the diets inhibited the growth and nutrient digestibility of broiler. The outputs of xylose from the hydrolyzation of wheat-based diet by xylanase should have no adverse effects on broiler performance.

Xylose: absorption, fermentation, and post-absorptive metabolism in the pig

“…In the fasted state, hepatic pyruvate carboxylase was linearly increased by xylose [ 19 ]. Because pyruvate carboxylase is a rate limiting enzyme for hepatic gluconeogenesis which is active when glycogen stores are depleted, such as occurs in starvation, this result corroborates reports that xylose depletes hepatic glycogen stores in poultry [ 18 , 39 ].…”

Dietary D-xylose effects on growth performance, portal nutrient fluxes, and energy expenditure in growing pigs1

“…In this study, final BW, growth rate, and feed efficiency decreased when D-xylose content in the diets increased. These observations are in agreement with previous results in pigs (Wise et al, 1954) and chickens (Wagh and Waibel, 1966;Schutte, 1990;Schutte et al, 1992;Peng et al, 2004), who also reported decreased weight gain and feed efficiency due to increasing dietary D-xylose content. An explanation for the reduced weight gain and feed efficiency may be due to the lower ME content of D-xylose compared with GLU as reported by Schutte et al (1991) and Verstegen et al (1997).…”

“…Feed intake was not affected by increasing dietary D-xylose content in the present study. In chickens, Peng et al (2004) reported that increasing dietary D-xylose content up to 40% linearly decreased feed consumption. Recently, we reported that up to 15% dietary D-xylose inclusion linearly decrease feed consumption in broiler chickens (Regassa et al, 2017).…”

“…Indeed, previous studies in chickens (Wagh and Waibel, 1966;Schutte, 1990) and pigs (Schutte et al, 1991;Verstegen et al, 1997) reported that the ME values reduced when diets contained high concentrations of D-xylose. Further, feeding broiler chickens up to 40% xylose decreased protein and fat digestibility (Peng et al, 2004), whereas high doses of D-xylose severely depleted liver and muscle glycogen Waibel, 1966, 1967;Peng et al, 2004), suggesting energy deprivation. Our recent study in broilers showed that 5% or more D-xylose reduced growth performance and utilization of nutrients linked to changes in hepatic enzymes and transcription factors involved in energy metabolism (Regassa et al, 2017).…”