Biodiesel co-products modified the rumen parameters of feedlot lambs but did not change methane production in vitro

ABSTRACT

Background: Intensification of livestock is a strategy that increases productivity, but the diets used to increase animal production efficiency are composed mainly of corn and soybean, thereby increasing competition between animals and humansfor the same food crops. This study evaluated nutrient intake, apparent digestibility of dry matter (DM) and nutrients, kinetics of gas production, and concentration of volatile fatty acids on diets with or without inclusion of biodiesel co-productsformulated for feedlot lambs. So, the hypothesis is that replace of traditional ingredients by biodiesel co-products changesrumen parameters and methane emissions.Materials, Methods & Results: The experiment was developed in São Paulo State University (Unesp), Jaboticabal, SP,Brazil, in Sheep Production Laboratory, which is owned to Animal Science Department. All trials developed in this studyused a feedlot system, where animals were kept in individual pen. Forty Ile de France lambs male non-castrated wereused in in vivo trial. To obtain rumen fluid, that was used in in vitro trial, four Santa Inês lambs with rumen cannula wereused. The treatments evaluated were four diets Control diet roughage + concentrate; PM20 roughage + concentrate withpeanut meal (PM) at 20% of DM; CG25 roughage + concentrate with crude glycerin (CG) at 25% of DM; and PMCGroughage + concentrate with PM at 10% of DM and CG at 12.5% of DM. The roughageconcentrate ratio was 4060 for allthese diets. The parameters of the in vitro and in vivo experiments used were completely randomized with four treatments.When significant, the means between treatments were compared using Tukey test (P < 0.05). There was no effect of coproduct inclusion on intake, except ether extract and neutral detergent fiber, which were higher for PM20 compared withCG25 diet. Apparent digestibility of dry matter (79.87%) and some nutrients (organic matter, crude protein, and neutraldetergent fiber)...