Effects of glycerol on the metabolism of broilers fed increasing glycerine levels

Abstract

This study evaluated the metabolic response of broilers fed diets containing increasing crude glycerine levels in two bioassays. Birds were house in metabolic cages, and were distributed according to a completely randomized experimental design with five treatments of 4 replicates each (1 st assay: 5 birds/ cage; 2 nd assay: 1-20 days = 8 birds/ cage, and 21-42 days = 4 birds/cage). Treatments consisted of a control diet based on corn and soybean meal, and four other diets containing 2.5%, 5.0%, 7.5% and 10.0% glycerine derived from biodiesel. In experiment I, there was no effect (p>0.05) of glycerol level on liver weight or blood parameters. Serum blood glycerol levels of the birds fed 10% crude glycerine increased during the first nine days of diet intake (p<0.05). In experiment II, water intake increased (p<0.05) in the birds fed 7.5 and 10.0% crude glycerine at 4 and 8 days of age. Feed intake increased (p<0.05) on days 8 and 12 in birds fed 2.5 and 7.5% glycerine. Fecal moisture increased (p<0.05) in birds fed diets with 5.0, 7.5, and 10.0% crude glycerine on days 16 and 20. Ileal content moisture was not different (p>0.05) among treatments when birds were 42 days old. High dietary glycerine levels may induce metabolic change in broilers, such as increased blood glycerol level, water intake and fecal moisture.

Evaluation of Dietary Glycerin Inclusion During Different Broiler Rearing Phases

“…Gianfelici (2009) and Romano et al (2014) observed that levels higher than 7.5% of glycerin in broiler diets increased water consumption and excretion, which may have adverse effects on the field due to higher litter moisture. Glycerin is a low molecular weight hydrophilic compound, which is easily excreted by the kidneys.…”

Impact of increasing crude glycerine levels in diet on growth, carcass traits, body measurements and blood cholesterol in growing Japanese quails

“…It was found that raw glycerine could be efficiently utilized when included at levels up to 10% in the starter diet phase. Romano et al (2014) observed a linear interaction between glycerine levels and bird age on daily feed intake. Bernardino et al (2015) studied the influence of pure and semi-pure glycerine addition with varying levels (0, 17.5, 35, 52.5 and 70 g · kg ) on broiler performance.…”

Effects of the Addition of Pure Glycerin Supplementation in the Drinking Water on the Performance of Broilers Submitted to Heat Stress and Feed Restriction

“…Although there are many studies showed positive results of the glycerin as an energy supplement for athlete animals and humans on hot days (Schott et al, 2001;Kavouras et al, 2006;Dozier et al, 2008;Patlar et al, 2012;Romano et al, 2014), there are no studies on the effects of glycerin inclusion in the drinking water of broilers submitted to heat stress. Therefore, the objective of this study was to evaluate the supplementation of pure glycerin the drinking water on the performance of broilers submitted to feed restriction and to cyclic heat stress.…”