Orange molasses as a new energy ingredient for feedlot lambs in Brazil

Abstract

The objectives of this experiment were to evaluate the effects of increasing levels of orange molasses in replacement of int corn grain in high-concentrate diets on dry matter intake (DMI), average daily gain (ADG) and feed e ciency (FE) of feedlot lambs. Thirty male lambs without de ned racial pattern (30.3 ± 5.3 kg of initial BW; mean ± SD) were used in a randomized complete block design with 10 blocks and 3 treatments. The treatments were de ned by partial replacement of int corn by orange molasses in the diet with 90% of concentrate and 10% of Cynodon spp hay, as follow: 0OM -control diet without orange molasses; 20OM -20% of orange molasses replacing int corn and 40OM -40% of orange molasses replacing int corn (DM basis). The experiment lasted 72 days divided into 3 subperiods, with 1subperiod of 16 days and 2 subperiods of 28 days. Animals were weighed after a16-h fast on days 1, 16, 44 and 72 of the experimental periods to determine the ADG and FE. The DMI, ADG and FE showed an interaction between treatments and experimental periods. The DMI in the rst period decreased linearly (P < 0.01), in the third period, there was no effect of treatments (P > 0.05) on DMI. The ADG decreased linearly (P < 0.01) in the rst period as the orange molasses increased. Otherwise, in the third period, ADG increased linearly (P = 0.05) as int corn was replacement by orange molasses. The FE showed an interaction between treatment and period (P = 0.09). In the rst period had a decreased linear effect, in the third period there was a trend (P = 0.07) of linear increased. There was no difference between the diets regarding the nal BW of the lambs. In conclusion, the orange molasses can replace up to 40% of int corn in diets for feedlot lambs without affecting nal BW. However, it is important to consider the adaptation time proved to be very important for better use of orange molasses as a source of energy in diets for lambs.