Yeast culture combined with Lithothamnium increases the performance of feedlot steers

The objective of this study was to evaluate the effectiveness of adding yeast culture (Saccharomyces cerevisiae) combined with Lithothamnium to the diet of feedlot steers through weight gain, dry matter (DM) intake, apparent DM digestibility, and carcass ultrasonography: T1 - diet with yeast culture (7g animal day-1); T2 - diet with Lithothamnium (60g animal day-1); T3 - diet with yeast culture (7g animal day1) plus Lithothamnium (60g animal day-1). Thirty-six ½ Angus Nellore steers, intact males, with an average initial weight of 350 kg and an average age of 11 months, were assigned to a completely randomized design composed of three treatments with six replications; each replication was represented by a pen with two animals. The animals were fed ad libitum twice daily, at 6:00 and 17:00 h. The diets consisted of 40% corn silage and 60% concentrate, on a DM basis. The feedlot period was 78 days, with 10 days of adaptation and 68 experimental days divided into two periods of 34 days each. The addition of yeast culture combined or not with Lithothamnium to the diet resulted in greater average daily gain (1.557 and 1.609 versus 1.440 kg day-1), better feed conversion ratio (6.72 and 6.91 versus 7.57 kg DM kg body weight gain-1), and increased the subcutaneous fat thickness (6.69 and 6.71 versus 5.72 mm). This is because of the higher apparent DM digestibility of the diet (71.11 and 69.32 versus 67.51%) compared to the isolated use of Lithothamnium. The addition of yeast culture, combined or not with Lithothamnium in the diet of feedlot steers, is recommended to improve animal performance and increase fat deposition in the carcass.