title: Chemical composition and ruminal nutrient degradability of fresh and ensiled amaranth forage.
abstract: BACKGROUND
  Amaranth is a crop with potential as a source of forage for ruminants that has not been well characterized. A study was conducted to determine the impact of ensiling on the nutritional quality and ruminal degradability of forage from two amaranth cultivars adapted to North America (i.e. Plainsman and D136). In particular, quantification and some microscopic characterization of oxalate found in amaranth were performed as it is an antiquality compound of concern.
  
  
  RESULTS
  There were limited interactions between cultivars and ensiling for most variables. Differences in chemical composition between amaranth cultivars were also limited. Ensiling reduced non-structural carbohydrate and true protein contents. The proportion of acid detergent protein was high in fresh and ensiled forages of both cultivars (average of 177 g kg(-1) crude protein). Total oxalate content averaged 30 and 25 g kg(-1) in fresh and ensiled forages respectively. Ensiling reduced soluble oxalate content. Crystals observed in amaranth were calcium oxalate druses found mostly in idioblast cells in leaf mesophyll and parenchyma of primary and secondary veins. In situ ruminal degradability data indicated that both fresh and ensiled amaranth are highly degradable in the rumen.
  
  
  CONCLUSIONS
  This study confirms that amaranth is a suitable forage for ruminant animals. Its chemical composition is comparable, for most variables, to that of other commonly used forage species.
authors: Department of Plant Science, McGill University, Macdonald Campus, 21111 Lakeshore Road, Sainte-Anne-de-Bellevue, QC, H9X 3 V9, Canada.
authors: Philippe
authors: P
authors: Seguin
authors: Arif F
authors: AF
authors: Mustafa
authors: Danielle J
authors: DJ
authors: Donnelly
authors: Bruce
authors: B
authors: Gélinas
mesh_terms: D027721:Amaranthus / Q000737:chemistry* / Q000145:classification; D000818:Animals; D001682:Biological Availability; D002129:Calcium Oxalate / Q000737:chemistry; D003460:Crystallization; D004032:Diet; D004040:Dietary Carbohydrates / Q000378:metabolism; D004044:Dietary Proteins / Q000378:metabolism; D004063:Digestion; D009656:North America; D009753:Nutritive Value; D010070:Oxalates / Q000378:metabolism*; D018515:Plant Leaves / Q000737:chemistry; D058526:Plant Vascular Bundle / Q000737:chemistry; D012417:Rumen / Q000378:metabolism*; D012418:Ruminants; D012820:Silage; D013045:Species Specificity
chemical_list: D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D010070:Oxalates; D002129:Calcium Oxalate
keywords: amaranth; forage quality; oxalate; protein fractions; ruminal degradability; silage