Digestible and metabolizable energy of crude glycerol for growing pigs1,2

Abstract

The apparent DE and ME values of crude glycerol for growing pigs were determined in 5 experiments using crude glycerol (86.95% glycerol) from a biodiesel production facility, which used soybean oil as the initial feedstock. Dietary treatments were 0, 5, or 10% glycerol addition to basal diets in Exp. 1; 0, 5, 10, or 20% glycerol addition to basal diets in Exp. 2; and 0 and 10% crude glycerol addition to the basal diets in Exp. 3, 4, and 5. Each diet was fed twice daily to pigs in individual metabolism crates. After a 10-d adjustment period, a 5-d balance trial was conducted. During the collection period, feces and urine were collected separately after each meal and stored at 0 degrees C until analyses. The GE of each dietary treatment and samples of urine and feces from each pig were determined by isoperibol bomb calorimetry. Digestible energy of the diet was calculated by subtracting fecal energy from the GE in the feed, whereas ME was calculated by subtracting the urinary energy from DE. The DE and ME values of crude glycerol were estimated as the slope of the linear relationship between either DE or ME intake from the experimental diet and feed intake. Among all experiments, the crude glycerol (86.95% glycerol) examined in this study was shown to have a DE of 3,344 +/- 8 kcal/kg and an ME of 3,207 +/- 10 kcal/kg, thereby providing a highly available energy source for growing pigs.

Níveis de glicerina para novilhas suplementadas em pastagens: desempenho, ingestão, eficiência alimentar e digestibilidade

“…A glicerina contém entre 80 a 95% de glicerol e impurezas, como água, sais, ésteres, álcool, óleo residual, os quais determinam menor valor deste coproduto no mercado (OOI et al, 2004). A glicerina bruta possui 86,95% de glicerol; 9,22% de umidade; 0,028% de metanol; 0,41% de proteína bruta; 0,12% de gordura; 3,19% de matéria mineral; 1,26% de sódio; 1,86% de potássio e 3.625 kcal/kg de energia bruta (LAMMERS et al, 2008). Segundo Südekum (2008), a glicerina pode apresentar teores variáveis de glicerol, água, metanol e ácidos graxos, sendo classificada de acordo com os níveis de glicerol na sua composição (baixa pureza 50 a 70%, média pureza e alta pureza acima de 99% de glicerol).…”

Application of Two Bioenergy Byproducts with Contrasting Carbon Availability to a Prairie Soil: Three-Year Crop Response and Changes in Soil Biological and Chemical Properties

“…There is a wide range of applications for pure glycerol in pharmaceutical, food and cosmetic industries, but the refining of crude glycerol to a high purity is costly and may not be profitable for small and medium size biodiesel production plants; especially when the market for glycerol is already saturated [13,14]. Glycerol has also been used as a feed ingredient in animal diets to reduce diet costs [13,14]. Research is ongoing to explore alternative methods of crude glycerol utilization to improve the economic feasibility of the biodiesel industry.…”

Addition of crude glycerin to pig diets: sow and litter performance, and metabolic and feed intake regulating hormones

“…Crude glycerin has an energy content similar to that of corn, and can be used by the pig as a source of energy when included in the diet (Lammers et al, 2008b;Kovács et al, 2011). Moreover, glycerol is a precursor of glucose, which participates in lipogenesis and can prevent protein catabolism (Tao et al, 1983).…”