Observatorio de I+D+i UPM

Memorias de investigación
Ponencias en congresos:
Nutrient supply estimations errors when using free ruminal bacteria as reference sample
Áreas de investigación
  • Productos de origen animal
The chemical composition of bacteria associated with solid (SAB) and liquid (LAB) rumen-digesta phases was studied to confirm errors when LAB is used as reference sample to estimate nutrient supply from SAB (González et al., 2012). Three rumen and duodenum cannulated wethers were fed three isoproteic diets for three successive periods. Diets included protein concentrates (sunflower meal and spring pea) untreated or treated with malic or ortophosphoric acid and heat supplied in this order. Diets were formulated with 45% oat (avena sativa) hay and 55% concentrate (fresh matter basis; 30% corn grain, 30% barley grain, 15% sunflower meal, 22% spring pea, 3% minerals and vitamins) and offered daily at 45 g/kg BW0.75 in six identical meals. Bacterial samples (SAB and LAB) were isolated after 12 d of continuous intraruminal infusion of (15NH4)2SO4 (25 mg 15N/d). Results were compared by variance analysis considering wethers (as blocks) and diets in the model. Compared with SAB, LAB showed consistently lower contents (g/kg DM) of OM (780 vs. 693; P < 0.001), starch- glucose (33.4 vs. 19.9; P = 0.013), and total lipids (221 vs. 113; P < 0.001), but greater CP content (402 vs. 429; P = 0.007) and 15N enrichment (atoms %: 0.0585 vs. 0.0817; P = 0.005). Present data fitted well with the relationship predicting SAB 15N enrichment from the same LAB value reported in the previously cited study (variation coefficient of the mean prediction error = 13.0%). The mean ratio 15N-SAB/15NLAB allows establishing CP supply from synthesized SAB is under evaluated by 25.6% when LAB is used as reference. This under evaluation was even greater for starch-glucose (44.2%) and lipids (61.9%) supply. These under evaluations were close to those previously reported by González et al., 2012. Taking into consideration that SAB is the main microbial source of nutrient supply, these errors should be factored in when attempting to improve ruminant nutrition. Predictions using 15N as marker are useful for correcting errors associated with the traditional use of LAB as reference sample, and therefore to obtain a more accurate estimate of microbial nutrient supply to the ruminant.
Nombre congreso
Joint Annual Meeting
Tipo de participación
Lugar del congreso
Fecha inicio congreso
Fecha fin congreso
Desde la página
Hasta la página
Título de las actas
J. Dairy Sci. Vol. 97, E-Suppl. 1
Esta actividad pertenece a memorias de investigación
  • Autor: Fernando Díaz Royón (UPM)
  • Autor: Jose Maria Arroyo Martinez (UPM)
  • Autor: Javier Gonzalez Cano (UPM)
Grupos de investigación, Departamentos, Centros e Institutos de I+D+i relacionados
  • Creador: Departamento: Producción Agraria
S2i 2023 Observatorio de investigación @ UPM con la colaboración del Consejo Social UPM
Cofinanciación del MINECO en el marco del Programa INNCIDE 2011 (OTR-2011-0236)
Cofinanciación del MINECO en el marco del Programa INNPACTO (IPT-020000-2010-22)