Abstract
Ammoniated rice straw was fed ad libitum with two levels of concentrate to twelve Suffolk ewes, each suckling two lambs. Ewes were individually penned throughout the first six weeks of lactation, and fed either 1.4% or 2.0% body weight of concentrate at the basis of dry matter.
Dry matter intake of concentrate in ewes fed 2.0% concentrate was higher than that fed 1.4% (P< 0.01). Dry matter intake of ammoniated rice straw in ewes fed 2.0% concentrate was lower than that fed 1.4% (P< 0.05). Total intake of crude protein and total digestible nutrients in ewes fed 2.0% concentrate were higher than that fed 1.4% (P< 0.01). Nutrient intake as a percentage of NRC requirements was about 80% and 100% in ewes fed 1.4% and 2.0% concentrate respectively.
Body weight reduction of ewes fed 2.0% concentrate was lower than that fed 1.4% (P< 0.05). Daily gain of lambs suckled by ewes fed 2.0% concentrate was higher than that suckled by ewes fed 1.4% concentrate (P < 0.01).
The concentration of serum free fatty acid in ewes fed 1.4% concentrate was elevated relative to those fed 2.0% concentrate, indicating more mobilization from the body's fat stores.
