Response of feedlot lambs receiving soybean molasses in different inclusions in high concentrate diets

Abstract

Soybean molasses (MSO) is a byproduct of protein concentrate production (soybean meal), which has high sugar concentrations and high potential to use in ruminant nutrition. For these reasons, two experiments will be undertaken, being the first one of animal performance in feedlot system, which will use 40 crossbreed lambs (Dorper × Santa Inês) in a randomized block design, receiving four diets with increasing inclusions of MSO (0, 100, 200 or 300g/kg on dry matter basis). Diets will be similar in energy and protein content, and the forage:concentrate ratio of the diet will be 20:80. In trial 1, the DM and nutrients intake, ingestive behavior, ruminal health and qualitative parameters of meat and quantitative of carcass will be evaluated. In the second experiment, the fermentative parameters will be studied, being the digestibility of DM and nutrients and in vitro gas production evaluated. For this trial, three ruminally-cannulated crossbred uncastrated male Santa Inês × Dorper sheep will be used as inoculum donors. The digestibility of DM and nutrients will be developed in Ankon® Daisy IncubatorII apparatus. In vitro greenhouse gas production and quality, disappearance of DM and nutrients, concentrations of NH3-N and VFA, and pH of incubations will be evaluated at the moment of incubation (0 hour) and after 2, 4, 8, 12 and 24 hours of incubation, in 3 incubations. The data will be evaluated as a randomized blocks design, with repeated measurement in time with 8 replicates per treatment per hour, considering each incubation as a block. Data will be analyzed using SAS statistical program. Our hypothesis is that the replacement of corn grain by MSO will improve the animal performance, carcass traits, ingestive behavior, ruminal health, in vitro digestibility of DM and nutrients, and then consequently reducing the greenhouse gas production. In this sense, the objective of this work will be to evaluate the effects of the increasing inclusion of MSO in diets for feedlot lambs on performance, quantitative carcass and meat qualitative characteristics, digestibility of DM and nutrients and in vitro ruminal parameters. (AU)