Inoculant Effects on Ensiling and \u3ci\u3ein Vitro\u3c/i\u3e Gas Production in Lucerne Silage

Inoculants are the most common additives used in making silage. While inoculant effects on fermentation and dry matter (DM) recovery are understood, animal performance effects are often greater than expected. In vitro analyses may help uncover how inoculants affect rumen fermentation and ultimately dairy cattle performance. Our objective was to study how inoculation of lucerne silage affected in vitro gas production

\u3cem\u3eIn Vitro\u3c/em\u3e Gas Production and Bacterial Biomass Estimation for Lucerne Silage Inoculated With One of Three Lactic Acid Bacterial Inoculants

Silages inoculated with microbial inoculants frequently have a lower pH than non-inoculated crops. Less often inoculated crops have a positive effect on milk production (Weinberg & Muck, 1996). One hypothesis is that bacterial inoculants produce a probiotic effect that could enhance animal performance (Weinberg & Muck, 1996). Our objective was to use the method of Blümmel et al. (1997) to study differences in in vitro fermentation among lucerne silages inoculated with three microbial inoculants

Inoculant effects on alfalfa silage: Fermentation products and nutritive value

The effect of 14 microbial inoculants on the fermentation and nutritive value of alfalfa silages was studied under laboratory conditions. The first cut (477 g of dry matter/kg) and second cut (393 g of dry matter/kg) of a second-year alfalfa stand were ensiled in 2 trials. In both trials alfalfa was harvested with standard field equipment. All inoculants were applied at 1.0 x 10(6) cfu/g of crop. Uninoculated silages served as controls. After inoculants were added, the chopped forages were ensiled in 1.0-and 0.5-L anaerobic glass jars, respectively, at a density of 500 g/L. Each trial had 15 treatments (uninoculated control and 14 inoculants), with 4 silos per treatment. Silos were stored for a minimum of 30 d at room temperature (similar to 22 degrees C). In first-cut silage, all inoculants but one reduced pH relative to the uninoculated control, and all but 2 of the homofermentative strains shifted fermentation toward lactic acid. In second-cut silage, the epiphytic lactic acid bacterial population was 2.7 x 10(7) cfu/g, and only commercial inoculants produced significant shifts in fermentation. Overall, microbial inoculants generally had a positive effect on alfalfa silage characteristics in terms of lower pH and shifting fermentation toward lactic acid with homofermentative lactic acid bacteria or toward acetic acid with heterofermentative lactic acid bacteria, Lactobacillus buchneri. These effects were stronger in the commercial products tested. In spite of the positive effects on silage fermentation, 48-h in vitro true DM digestibility was not improved by inoculation with lactic acid bacteria

Inoculant effects on alfalfa silage: In vitro gas and volatile fatty acid production

Alfalfa silages from 2 similar trials were analyzed for in vitro ruminal gas production. In both trials, there were 15 treatments: alfalfa treated at ensiling with 1 of 14 lactic acid bacterial inoculants or untreated alfalfa. First-cut (477 g of dry matter/kg) and second-cut (393 g of dry matter/kg) alfalfa were ensiled in glass jars for a minimum of 35 d at room temperature (similar to 22 degrees C). At opening, a portion of each silage was wet-ground with a mixer. Each silage was then assessed for in vitro ruminal gas production in 3 replicate runs with the wet-ground silage, 1 on the fresh silage and 2 on frozen and thawed silage. In vitro gas production was measured in 160-mL sealed serum vials incubated at 39 degrees C. One gram of silage was incubated with 17.1 mL of nutrient solution, 0.9 mL of reducing solution, and 12 mL of ruminal inoculum (1: 2 vol/vol mixture of rumen fluid and buffer). Gas production was measured manually by using a pressure gauge at 3, 6, 9, 24, 48, and 96 h. At 96 h, the rumen fluid was analyzed for pH and volatile fatty acids. In the 2 trials, the untreated control silage produced either numerically the highest or one of the highest levels of gas production per unit of dry matter incubated. In first-cut silage, 9 of the inoculant treatments at 9 h and 4 treatments at 96 h had reduced gas production compared with the control. In second-cut silage, 10 inoculant treatments at both 9 and 96 h had reduced gas production compared with the control. Furthermore, in first-cut silage, the fraction of total gas production at 3, 6, and 9 h was numerically the highest for the control, and only 4 treatments were not significantly lower than the control at 9 h. In second-cut silage, 2 of 14 inoculated treatments produced faster fractional rates of gas production than the control, but most inoculated treatments had numerically slower fractional rates (4 significant) in the first 9 h. The in vitro fermented wet-ground control silages had one of the highest acetate: propionate ratios in both trials, significantly higher than 12 and 8 of the inoculated treatments in first- and second-cut silage, respectively. The response in acetate: propionate ratio in both cuts was similar, even though the control silage was highest in lactic acid in one trial and lowest in the other. Overall, inoculation of crops at ensiling appears to affect in vitro ruminal fermentation of wet-ground silages, even in the absence of large effects during silage fermentation

VOLUMEN 14, NÚMERO 28 (1980)

ACTIVIDAD SÍSMICA EN EL DEPARTAMENTO DE SANTANDER. Gómez Padilla, J. A.EVOLUCIÓN GEOLÓGICA DE LA CUENCA PACÍFICA (GEOSINCLINAL DE BOLÍVAR), SECTOR NOROCCIDENTAL DE SURAMÉRICA. Pérez Téllez, G.GEOLOGÍA DE LA CUENCA DEL PUTUMAYO. Govea, R. C., Aguilera, H

VOLUMEN 14, NÚMERO 28 (1980)

ACTIVIDAD SÍSMICA EN EL DEPARTAMENTO DE SANTANDER. Gómez Padilla, J. A.EVOLUCIÓN GEOLÓGICA DE LA CUENCA PACÍFICA (GEOSINCLINAL DE BOLÍVAR), SECTOR NOROCCIDENTAL DE SURAMÉRICA. Pérez Téllez, G.GEOLOGÍA DE LA CUENCA DEL PUTUMAYO. Govea, R. C., Aguilera, H

The Absolute Magnitude of RRc Variables From Statistical Parallax

We present the first definitive measurement of the absolute magnitude of RR Lyrae c-type variable stars (RRc) determined purely from statistical parallax. We use a sample of 247 RRc selected from the All Sky Automated Survey (ASAS) for which high-quality light curves, photometry and proper motions are available. We obtain high-resolution echelle spectra for these objects to determine radial velocities and abundances as part of the Carnegie RR Lyrae Survey (CARRS). We find that M_(V,RRc) = 0.52 +/- 0.11 at a mean metallicity of [Fe/H] = -1.59. This is to be compared with previous estimates for RRab stars (M_(V,RRab) = 0.75 +/- 0.13 and the only direct measurement of an RRc absolute magnitude (RZ Cephei, M_(V, RRc) = 0.27 +/- 0.17). We find the bulk velocity of the halo to be (W_pi, W_theta, W_z) = (10.9,34.9,7.2) km/s in the radial, rotational and vertical directions with dispersions (sigma_(W_pi), sigma_(W_theta), sigma_(W_z)) = (154.7, 103.6, 93.8) km/s. For the disk, we find (W_pi, W_theta, W_z) = (8.5, 213.2, -22.1) km/s with dispersions (sigma_(W_pi), sigma_(W_theta), sigma_(W_z)) = (63.5, 49.6, 51.3) km/s. Finally, we suggest that UCAC2 proper motion errors may be overestimated by about 25%Comment: Submitted to ApJ. 11 pages including 6 figure