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The objective of this study was to evaluate the effects of dietary supplementation with live yeast (Saccharomyces cerevisiae), mannan-oligosaccharides and the combination of these additives on the inflammatory response, ruminal parameters and rumen morphology of sheep fed a high grain-based diet. Thirty-Two Dorper x Santa Ines crossbred lambs with an average weight of 24±2 kg were distributed in a completely randomized design. The animals were housed in individual stalls and fed ad libitum. Diet treatments were: Control (without additive); LY (2 g/kg DM of live yeast, Saccharomyces cerevisiae), MOS (2 g/kg DM of mannan-oligosaccharides) and LY+MOS (2 g/kg DM of LY + 2 g/kg DM of MOS). The experiment lasted 42 days. The supplementation with MOS alone and the additives combination resulted in increased ruminal pH (P<0.01), while the total concentrations of short chain fatty acids (SCFA) in the rumen were higher (P<0.05) only in the diets with LY and MOS. Ammonia (NH3) concentration in the rumen decreased (P<0.04) with the additives usage. Diets with LY, MOS and with additives combination reduced (P<0.01) the levels of lipopolysaccharides (LPS) in the plasma with values of 0.46; 0.44 and 0.04 EU/mL, respectively when compared to the control (0.93 EU/mL). MOS and LY+MOS treatments had reduced stratum corneum thickness (P<0.01) in comparison to the control treatment. The total thickness of ruminal epithelium was lower with the addition of MOS in the diet (P<0.03) than with LY additive. The incidence and severity of hepatic abscesses in animals whose diet was supplemented with LY and LY+MOS was lower (P<0.05) than in animals fed the control diet. The use of LY, MOS and LY+MOS in the high-concentrate diets for sheep reduced NH3 concentrations and LPS translocation into the bloodstream. Diets containing MOS and LY+MOS enhanced the health of the ruminal epithelium by reducing the thickness of the stratum corneum, and diets containing LY and LY+MOS decreased the incidence and severity of hepatic abscesses.

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The objectives of this study were to determine the range of neutral detergent fibre (NDF) digestibility across sugarcane varieties and predict dry-matter (DM) and NDF digestibility based on morphological and chemical composition. Whole plants of thirty-two commercial varieties were collected after 12 months regrowth (second cut) and evaluated for morphological traits, chemical composition, in situ digestibility of NDF (NDFD) and of DM (DMD), in vitro NDFD (IVNDFD) and gas production dynamics from isolated NDF. The content of NDF ranged from 404 to 547 g kg À1 DM, DMD was between 593 and 739 g kg À1 and NDFD varied from 270 to 363 g kg À1 . Cluster and discriminant analyses for NDFD agglomerated sugarcane genotypes into three groups (high, medium and low NDFD). The contents of NDF and lignin were the best univariate predictors of sugarcane DMD and NDFD respectively. Therefore, associating NDF and lignin improved the accuracy of DMD prediction. Associating lignin concentration with the number of dry leaves and stalk length significantly improved the goodness of fit of NDFD prediction. Contrary to expectations, silicon concentration was not related to NDFD. The principal component analysis patterned the content of neutral detergent solubles, NDFD and variables related to DM yield in different components. Hence, these characteristics would coexist in the same variety. Based on Lucas test and kinetics of gas production from NDF, sugarcane potentially digestible NDF (pdNDF) can be considered almost uniform (pdNDF digestibility = 677 g kg À1 ). In conclusion, associating chemical composition and morphological traits can successfully improve the screening of sugarcane genotypes for animal nutrition.

The objective of this study was to evaluate the effects of diet supplementation with live yeast (Saccharomyces cerevisiae) and mannan-oligosaccharides (MOS) on ruminal parameters, nutrient digestibility, and the inflammatory response in cattle fed grain-based diets. Three Holstein steers (body weight of 497±3 kg) with ruminal and duodenal cannulas were assigned to a 3 × 3 Latin square design. The animals were kept in individual pens and fed a diet containing 5% sugarcane bagasse and 95% concentrate (906.5 g/kg ground corn). Diet treatments were Control (without additive), Yeast (1.5 g/kg DM live yeast Saccharomyces cerevisiae, NCYC 996) and MOS (1.5 g/kg DM MOS, β-glucans and mannan). Dry matter intake, ruminal, intestinal, and total digestibility of nutrients were not affected by the treatments. The ruminal concentration of isobutyric acid increased in animals fed on diets supplemented with Yeast and MOS, whereas isovaleric acid increased with Yeast and decreased with MOS supplementation. Dietary supplementation with Yeast and MOS increased pH and decreased ammonia concentration in the rumen. Lipopolysaccharide (LPS) concentrations in the rumen and duodenal fluid were not influenced by the additives. However, both Yeast and MOS decreased the plasma levels of LPS and serum amyloid A (SAA). In conclusion, when high-concentrate diets fed to beef cattle are supplemented with either Yeast or MOS, ruminal pH is increased, LPS translocation into the blood stream is decreased, and blood SAA concentration is decreased. These factors reduce the inflammation caused by consumption of grain-based diets, and either supplement could be used to improve the rumen environment in beef cattle susceptible to ruminal subacute acidosis.