Página principal > Artículos > Differences in nutritional characteristics of three varieties of sorghum grain determine their in vitro rumen fermentation
Resumen: The effect of phenolic compounds and protein matrix on microbial fermentation of three sorghtun grains (S1, S2 and S3) were studied in vitro. Total phenolics and total tannins concentration (g/kg dry matter, DM) were 1.5 and 0.2 for S1, 19.3 and 8.1 for S2 and 2.6 and 1.3 for S3. Protein enzymatic digestibility was 0.614, 0.226 and 0.454, respectively. Trial 1 was conducted for 24 h, without or with polyethylene glycol (PEG) to determine the effect of phenolic compounds on fermentation. Without PEG, gas production for S1 was the highest after 24 h (257, 237 and 238 mL/g organic matter, for S1, S2 and S3; p<0.05), and higher proportion of propionate at the expense of acetate was recorded with S3 after 6 h. Gas produced with S1 and S3 remained unaffected (p>0.10), but increased in S2 by 0.21 to 0.30 with vs. without PEG. No differences in gas production between S1 and S2 were observed with PEG, S3 recording the lowest (p<0.05) values from 8 h onwards. Addition of PEG reduced proportion of butyrate (p<0.05) and increased three-fold lactate (1.62 vs. 4.98 mM; p<0.001). In Trial 2 (12 h) gas production followed a similar pattern. Without PEG, starch disappearance was the highest in S1 (0.356, 0.231 and 0.216, respectively), but no differences were recorded with PEG. Considering differences in protein digestibility and the effect of phenolic compounds, the effect of starch nature and structure on fermentation is apparently minor. Colour of grain is not necessarily related to phenolic compounds proportion or rumen utilization. Idioma: Inglés DOI: 10.5424/sjar/2018163-13010 Año: 2018 Publicado en: Spanish Journal of Agricultural Research 16, 3 (2018), e0608 [10 pp] ISSN: 1695-971X Factor impacto JCR: 1.035 (2018) Categ. JCR: AGRICULTURE, MULTIDISCIPLINARY rank: 28 / 56 = 0.5 (2018) - Q2 - T2 Factor impacto SCIMAGO: 0.391 - Agronomy and Crop Science (Q2)