Setaria (Setaria sphacelata
) is a tall tropical perennial forage that is native to Africa. S. sphacelata
has been introduced and is now widespread in most tropical and subtropical regions worldwide. It has multiple subspecies and is often used for pasture grass for other livestock. S. sphacelata
has a cylindrical spike-like panicle with an inflorescence structure that varies in color from brown to purplish brown.
All parts of S. sphacelata
have the potential to accumulate high levels of oxalates (4.5%-6.7% of DM in 3-week regrowth).
Such high levels of oxalates off balance the Ca:P ratio, resulting in nutritional secondary hyperparathyroidism (also known as 'big head disease'
. Mares and foals are the most susceptible and symptoms can develop within 2 months of grazing. Osteodystrophy in horses has been associated with prolonged ingestion of S. sphacelata
containing moderate (5%) concentrations of oxalates.