Crude glycerin is an efficient alternative to corn in the diet of feedlot lambs

The objective of this study was to evaluate the intake, digestibility, nitrogen balance, and performance of feedlot lambs fed diets containing crude glycerin. A total of 30 Ile de France lambs were confined to individual pens at an average age of 45 d: 15.1 kg initial body weight and 32.2 kg final body weight. The animals were distributed in a completely randomized design and fed three diets containing fresh sugarcane as forage (50 %) and concentrate (50 %), with or without the inclusion of 100 and 200 g vegetable crude glycerin per kilogram dry matter (DM) replacing corn. Dietary glycerin inclusion reduced the intake of ether extract (P<0.001) and total carbohydrates (P=0.048) as well as the apparent digestibility of ether extract (P<0.001), but it had no effect on the intake and digestibility of the other nutrients nor on lamb performance. The apparent nitrogen balance of lambs on the three diets was positive. Although it does not affect the intake and digestibility of most nutrients, the inclusion of 100 and 200 g kg−1 DM of crude glycerin in the diet tends to worsen lamb performance, indicating that the ideal level of inclusion should be below 100 g kg−1 DM of crude glycerin.

Feeding Crude Glycerin to Finishing Iberian Crossbred Pigs: Effects on Growth Performance, Nutrient Digestibility, and Blood Parameters

A total of 192 Iberian × Duroc pigs kept under intensive conditions were used to investigate the effects of feeding crude glycerin on growth performance, nutrient digestibility, and blood parameters. Animals were blocked by initial body weight (96.0 ± 11.3 kg) and allotted to pens (16 pigs per pen). Pens were assigned randomly to one of three dietary treatments (four pens per treatment). Dietary treatments contained 0, 5, or 10% of crude glycerin proportionally substituting for wheat (G0, G5, and G10, respectively). Diets were formulated to be isoenergetic and isoaminoacidic. No significant effect of crude glycerin was observed on average daily gain, average feed intake, or feed conversion ratio. The apparent total tract digestibility of dry matter, organic matter, and crude protein was no different between treatments. Total serum protein, albumin, glucose, insulin, and IGF-1 were not affected by glycerin inclusion. In conclusion, crude glycerin up to 100 g/kg can be included in the diets of finishing Iberian crossbred pigs without any negative effect on growth performance, digestibility, or serum metabolic parameters.

Glicerol en el comportamiento productivo y características de la canal y carne de cabras: un metaanálisis

El objetivo del presente estudio meta-analítico fue evaluar el efecto del glicerol en la dieta sobre el comportamiento productivo, digestibilidad de nutrientes y las características de la canal y carne de cabras en engorde. Se hizo una revisión sistemática utilizando las bases de datos de Google Scholar, ScienceDirect y SciELO. Palabras clave como crude glycerin, intake, goat, kids, carcass, meat quality fueron utilizados. Como criterios de inclusión de los artículos científicos se consideraron la presencia de un tratamiento testigo (0% de glicerol) y por lo menos un porcentaje de glicerol en la dieta, datos referentes a la digestibilidad de los nutrientes, respuesta productiva, características de la canal y carne y nivel de glicerol en la glicerina bruta en trabajos publicados entre 2014 y 2019. Se seleccionaron 56 artículos, de los cuales 11 reunieron los criterios de inclusión. Ante la heterogeneidad o amplitud de los niveles de glicerol, los niveles fueron agrupados: 0, 1.27-4.38 y 6.40-9.60% de glicerol en base a la materia seca de la dieta. Análisis de normalidad, variancia y de regresión fueron realizadas a partir de los datos de cada variable dentro de cada nivel de glicerol en la dieta. Se evidenció la alta variación de los niveles de glicerol en glicerina bruta. Glicerol hasta 9.60% en la dieta no compromete la digestibilidad, consumo, principales características de la canal y carne de cabra.

Using glycerin with chitosan extracted from shrimp residue to enhance rumen fermentation and feed use in native Thai bulls

Background and Aim: Crude glycerin is changed to propionate in the rumen, while chitosan can be used as a feed supplement to increase propionic acid concentration and decrease methane (CH4) production. We hypothesized that supplementation with a combination of a high level of crude glycerin with chitosan could have a beneficial effect on ruminal fermentation and mitigate CH4 production. This study aimed to explore the combined effects of crude glycerin and chitosan supplementation on nutrient digestibility, rumen fermentation, and CH4 calculation in native Thai bulls. Materials and Methods: Four 2-year-old native Thai bulls, weighing 150±20 kg, were kept in a 2×2 factorial arrangement in a 4×4 Latin square design. Factor A represented the incorporation of crude glycerin at 10.5% and 21% of the dry matter (DM) of a total mixed ration (TMR), and factor B represented the supplementation of chitosan at 1% and 2% DM of a TMR. Results: Increasing levels of crude glycerin at 21% decreased DM intake by 0.62 kg/day compared with 10.5% crude glycerin (p<0.05), whereas nutrient digestibility did not change (p>0.05). The incorporated crude glycerin and supplemented chitosan levels did not affect the pH, temperature, concentrations of ammonia-nitrogen, microbial population, and blood urea nitrogen (p>0.05). Supplemented chitosan and incorporated crude glycerin did not show any interaction effects on the molar portions and total volatile fatty acids (VFAs), except estimated CH4. Increasing the incorporated crude glycerin levels increased propionate and decreased the ratio of acetate to propionate ratio, whereas levels of butyrate, acetate, and total VFAs were unchanged. The combination of crude glycerin at 21% in the TMR with chitosan at 2% reduced CH4 estimation by 5.08% compared with the other feed treatment. Conclusion: Increasing incorporated crude glycerin levels in a TMR significantly elevated the propionate concentration, whereas combining 21% crude glycerin in the TMR diet with 2% chitosan supplementation could depress CH4 estimation more effectively than adding one of these supplements alone.