Functional additives, such as autolyzed yeasts, have been used to achieve greater production efficiency and animal health. These compounds are also alternatives to the use of performance-enhancing antimicrobials. The objective was to evaluate the productive performance, ingestive behavior, apparent digestibility of feed DM and the carcass characteristics of beef steers finished in feedlot receiving autolyzed yeasts in the diet. The experimental design was randomized blocks, consisting of three treatments and six repetitions, where each repetition was represented by a stall with two animals. 36 bulls, ½ Angus × ½ Nelore blood, from the same herd, with an average age of 11 months and an average body weight of ± 330 kg were used.The treatments were as follows: CON - yeast-free diet; Y4 - yeast diet (4 g animal day-1) and Y7 - yeast diet (7 g animal day-1). The product used is a functional ingredient containing the yeast Saccharomyces cerevisiae. The inclusion of autolyzed yeasts resulted in greater daily body weight gain and better feed conversion in the initial feedlot phase. The apparent digestibility of DM of diets containing autolyzed yeast was superior to the control diet, and its use did not interfere with the animal ingestive behavior. Supplementation with autolyzed yeasts at the inclusion level of 4 g day-1 promoted better results in the finishing of feedlot steers, and that the supplemented groups (4 g animal day-1 and 7 g animal day-1) achieved the same degree of carcass finishing, higher than the control group.

The objective was to evaluate the efficiency of two bacterial inoculants, 11CFT and 11C33, with different genera of lactic acid bacteria on the chemical and fermentation composition of the silage, and the temperature and pH behavior of the silage during the feed out period. The experimental design used was randomized blocks, with three treatments: corn silage without inoculant (control); corn silage with 11CFT inoculant (consisting of strains of Lactobacillus buchneri and L. casei); and corn silage with 11C33 inoculant (consisting of strains of L. buchneri, L. plantarum and Enterococcus faecium). The use of both inoculants increased the concentration of lactic acid in the silage (22.42 g kg-1 for control against 36.00 and 33.33 g kg-1 for 11CFT and 11C33, respectively) and reduced aerobic dry matter losses. The silage treated with 11C33 obtained a higher concentration of acetic acid (17.44 g kg-1) and propionic acid (2.08 g kg-1). The 11CFT inoculant provided a lower concentration of ethanol, however, without differing from the silage with 11C33 (0.70 and 1.61 g kg-1, respectively). Even without variations in temperature and pH at silage unloading, the use of the 11C33 inoculant generated a higher concentration of acetic and propionic acid, providing better aerobic stability days after unloading. Both inoculants also improved the in situ ruminal digestibility of corn silage compared to control silage. They provide an increase in the content of lactic and propionic acids, which assist to reduce dry matter losses and ethanol production. There were no variations in temperature and pH at the silo unloading, however, the use of the 11C33 inoculant generated a higher concentration of acetic and propionic acids providing better aerobic stability after exposure to air.

This study aimed to evaluate the productive performance, dry matter intake, apparent digestibility and ingestive behavior of feedlot calves fed corn silage from the feed out face of trench silos with different types of sealing. The animals were divided into three treatments with four repetitions: Conventional seal - double-sided polyethylene of 110µm thickness; Double-sided seal - double-sided polyethylene of 200µm thickness; and Double seal - composed of double face polyethylene with a thickness of 80µm superimposed on a polyamide translucent vacuum film with a thickness of 20µm. The use of double face sealing provided 12.63% increase in average daily gain and improved food conversion by 0.62 percentage points. The apparent digestibility of the diet with double-face sealing system silage was 4.30% higher than the diet with double-face sealing silage and 11.00% higher than the diet with conventional sealing silage. It is recommended to use the double face sealing with 200µm polyethylene and double face sealing with 80µm thick polyethylene on top of a 20µm thick polyamide translucent vacuum film.

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The objective of this study was to evaluate the efficiency of different types of sealing on the physical losses of dry matter, chemical and fermentation characteristics and in situ digestibility of the dry matter of corn silage stored in the feed out face (ramp) of trench silos. The experimental design used randomized blocks, composed of three treatments, namely: T1 - corn silage preserved with double-sided polyethylene of 110 μm thickness (conventional seal); T2 - corn silage preserved with double-sided polyethylene of 200 μm thickness (double-sided); and T3 - corn silage preserved with oxygen-impermeable film composed of double-sided polyethylene of 80 μm thickness on a translucent vacuum polyamide film of 20 μm thickness (double sealing), with four repetitions each. The use of double-sided polyethylene with 200 μm thickness (double-sided) and oxygen impermeable film composed of double-sided polyethylene and polyamide (double sealing), were effective in preserving the chemical composition, fermentation profile, raw protein composition and fiber quality, in addition, the use of these polymers resulted in greater ruminal digestibility of dry matter and reduced the pH, temperature, temperature gradient and physical losses of corn silage from the feed out face (ramp) of trench silos compared to the conventional sealing.