Glycerin in cattle feed: intake, digestibility, and ruminal and blood parameters

Abstract

This study aimed to evaluate the effects of glycerin supplements in the diet of beef cattle by assessing intake, apparent nutrient digestibility, ruminal pH, ruminal ammonia concentrations, and blood parameters. The study was conducted at the São Paulo State University (UNESP, Jaboticabal campus) using five crossbred cattle in an experiment employing a 5 x 5 Latin square design. Cattle diet treatments included zero, 50, 100, 150, and 200 g kg -1 dry matter of glycerin. Feed, leftover feed, and faeces were collected to determine intake and digestibility. Samples of ruminal liquid were collected at -1, 0, 1, 2, 4, 6 and 8 h after feeding to determine pH and ruminal ammonia. Blood was collected four hours after the morning feeding from the coccygeal vein. Replacing maize with glycerin resulted in lower concentrations of ether extract and non-fibre carbohydrates in the diets, leading to a linear decrease in the intake of these nutrients (P<0.05). The digestibility of neutral detergent fibre and nonfibre carbohydrates also decreased linearly with increasing dietary glycerin concentrations (P<0.05). The results for ruminal fermentation parameters showed a linear decrease (P<0.05) in the ruminal concentration of N-NH 3 with increasing dietary levels of glycerin; however, ruminal pH was not affected (P>0.05). Serum concentrations of urea, triglycerides, cholesterol, and plasma glucose concentrations were within normal ranges based on the literature. The inclusion of glycerin in the cattle diet altered rumen fermentation, reducing the concentration of N-NH 3 , the digestibility of neutral detergent fiber and non-fiber carbohydrates. g kg -1 de glicerina na MS. Para determinação do consumo e digestibilidade foram realizadas colheitas de alimentos, sobras e fezes. Para determinação do pH e amônia ruminal foram colhidas amostras de líquido ruminal nos tempos -1, 0, 1, 2, 4, 6 e 8 horas após a alimentação. As colheitas de sangue foram realizadas 4h após a alimentação matutina via veia coccígea. A substituição do milho pela glicerina resultou em menores concentrações de extrato etéreo e carboidratos não fibrosos nas dietas, o que levou a redução linear no consumo desses nutrientes (P<0,05). As digestibilidades da fibra em detergente neutro e de carboidratos não fibrosos apresentaram redução linear com o aumento da concentração de glicerina na dieta (P<0,05). Em relação à fermentação ruminal, houve decréscimo linear (P<0,05) na concentração ruminal de N-NH 3 com o aumento da inclusão desse subproduto, mas o pH ruminal não foi influenciado (P>0,05). As concentrações séricas de ureia, triglicerídeos e colesterol ficaram dentro dos níveis considerados normais pela literatura assim como as concentrações plasmáticas de glicose. A inclusão de glicerina na dieta de bovinos alterou a fermentação ruminal, reduzindo a concentração de N-NH 3 , a digestibilidade da fibra em detergente neutro e dos carboidratos não fibrosos. Palavras-chave: Biodiesel, fermentação ruminal, metabolismo, subproduto

Substituição do sorgo grão por glicerol não refinado em dietas para bovinos de corte

“…Several experiments demonstrated that DMI was not influenced by substituting different energy sources with crude glycerol in the diet (Mach, Bach & Devant 2009, p. 635;Moriel et al 2011, p. 4317;Ramos & Kerley 2012, pp. 896-7;Bartoň et al 2013, p. 55;Leão et al 2013, p. 424;Egea et al 2014, p. 675;Eiras et al 2014, p. 225;van Cleef et al 2014, p. 89;Buttrey et al 2015, p. 3701;Fávaro et al 2015Fávaro et al , p. 1499, which corroborate the findings in the present work. Conversely, a linear reduction in DMI was observed when dry-rolled cornbased diets were replaced by increasing levels of crude glycerol (0 to 15% of the total DM ration) fed to finishing steers (Hales et al 2015, p. 351).…”

“…896-8;Leão et al 2013, pp. 424-6;Eiras et al 2014, p. 225;van Cleef et al 2014, p. 89;Fávaro et al 2015Fávaro et al , p. 1499) and steamflaked corn (Buttrey et al 2015, pp. 3701-2).…”

“…Only the Brazilian National Production of biodiesel in 2016 was 3.8 mil- Bartoň et al 2013, p. 55;van Cleef et al 2014, p. 89;Egea et al 2014, p. 675;Eiras et al 2014, p. 225;Buttrey et al 2015, pp. 3701-2;Fávaro et al 2015Fávaro et al , p. 1499), but none of them have reported data about the substitution of sorghum grain with crude glycerol. We hypothesized that crude glycerol could partially replace sorghum grain in diets for beef cattle in a feedlot without compromising animal performance.…”

Effects of partial or total replacement of corn cracked grain with high concentrations of crude glycerin on rumen metabolism of crossbred sheep

“…The increase occurred probably due to the linear decrease observed in total VFA concentrations (40.1 in G0 and 23.8 mM/L in G30). However, in most of findings reported from studies using high concentrations of crude glycerin (up to 20%), authors did not observe alterations of rumen pH values (Chanjula et al, 2014;Favaro et al, 2015). Low ruminal pH may decrease DMI, fiber digestibility, and microbial yield and thus decrease animal production (Allen, 1997).…”

Inclusion of Crude Glycerin in Diets for Sheep

“…Crude glycerin has been recently studied as a great ingredient to prevent metabolic disorders when high inclusions of concentrate were offered to animals in feedlot systems [26,50,73,74]. Because of its own fermentation profile, crude glycerin can avoid severe reduction of ruminal pH and the development of rumen acidosis.…”