Very unique BIG Bull with horns done I believe in acrylic on wood. Back and sides painted black. Appears to be plywood? Definately a layered type wood. I believe probably 80s 90s which is when pastel color southwestern items were really popular. There are also round pieces of wood on back to keep the art slightly away from wall. 

Signed by what looks to me like "Bob Howard". I can find no person with this name online. Also is marked on back the name of piece "Desert Mirage". 

Dimensions/approx: 21 inches high, 24 inches wide