Variability among four laboratories of the filter bag technique to determine acid and neutral detergent fiber contents in ruminant feeds from Argentina.

The objective of this work was to evaluate the filter bag technique (FBT) in an ANKOM 200 fiber analyzer to assess its accuracy for the determination of acid and neutral detergent fiber (ADF and NDF, respectively) contents in common ruminant feeds from the temperate region of Argentina. The evaluation was done in a ring test of 4 laboratories. The 3 Argentine laboratories were from the College of Agronomy, University of Buenos Aires, the College of Agricultural Sciences of the Catholic University of Argentina, and the Balcarce Agricultural Experiment Station of the National Institute of Agricultural Technology (INTA). The fourth laboratory was from the Department of Animal Science of Cornell University, Ithaca, NY. The feeds utilized were soybean meal expeller, whole sunflower seed, corn grain, herbages of alfalfa, ryegrass, tall wheatgrass, weeping lovegrass, guinea and barley grasses, and silages of corn and of a natural grassland. Results indicated that values obtained in the 4 laboratories were consistent regardless of the laboratory where the analyses were performed. It was concluded that the FBT in the ANKOM instrument gave satisfactory results when used samples having a wide range of fiber contents, and that the among-laboratories variability of this methodology was low.