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Twenty Holstein cows at 168 ± 87 d in milk (mean ± SD) were assigned to a 4 × 4 Latin square design with a 2 × 2 factorial arrangement to evaluate the effects of 2 storage lengths (30 or 90 d) and the presence of sodium benzoate (control or 0.2% as fed) on the nutritive value of reconstituted sorghum grain silages (RSGS). For each treatment, dry ground sorghum grain was rehydrated to 35% moisture and ensiled in 200-L plastic drums. The treatments were RSGS stored for 30 d without sodium benzoate ( 30CON), RSGS stored for 30 d with sodium benzoate (30 BEN), RSGS stored for 90 d without sodium benzoate (90 CON) and RSGS stored for 90 d with sodium benzoate (90 BEN). Diets contained 16.3% RSGS. Silages stored for 90 d had higher concentrations of 1,2-propanediol, soluble protein, and ammonia nitrogen than did those stored for 30 d. Sodium benzoate reduced ethanol and ethyl-ester formation. Silages stored for 90 d had higher starch (89.3 vs. 86.9%) and protein (57.1 vs. 54.0%) digestibility compared with silages stored for 30 d. The ruminal acetate-to-propionate ratio tended to be lower in RSGS stored for 90 d than in RSGS stored for 30 d (3.75 vs. 3.34). Milk yield increased from 30.0 kg/d in cows fed RSGS stored for 30 d to 31.2 kg/d in cows fed RSGS stored for 90 d, without a change in dry matter intake (23.5 kg/d on average). Hence, feed efficiency and milk N efficiency also had tendencies to increase in cows fed RSGS stored for 90 d. Sodium benzoate did not alter cow performance but slightly increased plasma glucose (65.2 vs. 63.6 mg/dL). In conclusion, increasing the storage period of RSGS from 30 to 90 d improved starch and protein digestibility, milk yield, and feed efficiency.

The aim of this study was to evaluate the feed quality of reconstituted corn grain silage (RCGS), treated with chemical additives and stored for 15, 30, or 60 d in 5-L plastic buckets. Dry ground corn was rehydrated to 350 g·kg−1 and treated with either polysorbate 80 (2 L·t−1) (POL), propionic acid 28% (2 L·t−1) (PRO), Mycoflake™ (2 L·t−1-blend polysorbate 80 and propionic acid) (MYC) or nothing (CON). The effect of the length of storage was combined in a factorial arrangement with the additives. Ammonia-N increased from d-15 of storage. A treatment × storage length interaction was observed for ethanol content at d-60 of storage, and all treatments had lower ethanol concentration than CON. There was an interaction for butyric acid content at d-30 and d-60 of storage; CON showed higher butyric acid concentration than treated silages. Aerobic stability increased from d-15 to d-30. At d-15 of storage, the PRO and MYC treatments decreased the DM losses. The length of storage increased the ruminal in situ degradability of starch, and DM and MYC increased the DM degradability in 3.6 percentage units at 12 h of incubation, compared with POL. In conclusion, increasing the length of storage of the RCGS from d-15 to d-60 improved the starch and DM degradability. Mycoflake increased the availability of nutrients, and the length of storage enhanced the aggregation of particles; further, polysorbate 80 (Tween 80) might be further studied as a potential antimicrobial agent in silages.

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Effect of propionic acid and formic acid-based chemical additives on corn silages: fermentative profile and performance of dairy vaccines Organic acids have a great impact on silage fermentation and aerobic stability, acting very effectively against fungi and yeast. The objective of the present study was to evaluate the impact of a chemical additive in the fermentation profile of whole plant corn silage (WPCS) with high dry matter content and the dairy cows' performance fed with re-ensiled WPCS. The study was divided into two trials: Trial 1) The chemical additive Lupro-Mix® NA (35% propionic acid, 21% sodium formate, 20% formic acid, 4% sodium propionate and 20% water) was added in whole plant corn with high dry matter (~40%) and ensiled in experimental silos. The treatments were as follows: (i) without additive (control); (ii) Lupro-Mix® NA (4L per ton of natural matter). A completely randomized design with four replications per treatment was used. The additive was significantly efficient in reducing ethanol content, 1.2 propanediol, ethyl lactate, ethyl acetate, as well as DM losses. There was also a significant increase of propionic acid in relation to the control treatment, thus reflecting in greater aerobic stability of the treated mass. The silage with Lupro-Mix® NA showed a satisfactory result in the maintenance of the aerobic stability and reduction of the silage losses. Trial 2) The same additive tested in laboratory silos was tested on commercial scale silages in bag silos to feed lactating. In a cross over design, the cows were distributed in randomized blocks in 10 pairs of two animals, randomly distributed, within each block, in two treatments (i) silage without additive (control); (ii) silage with Lupro-Mix® NA (4L per ton of natural matter). The results pointed to a numerical reduction in the ingestion time of the animals fed treated silages. Similarly, numerically there was an increase in dry matter intake, milk yield, 4% fat corrected milk, and milk energy, as well as a trend towards increased protein content and yield. The use of Lupro-Mix® NA chemical additive reduces DM losses, improves aerobic stability and dairy cow performance.

Whole-plant corn silage (WPCS) is a major source of forage for dairy cattle in Brazil. Improved kernel processing may be especially advantageous when feeding corn hybrids with vitreous endosperms. Two experiments were conducted to evaluate the effects of the theoretical length of cut (TLOC) and ensiling time on WPCS particle size and kernel processing with two types of forage harvesters. In the first trial, the plant was harvested by a pull-type forage harvester (PTFH) at TLOCs of 3, 6 and 9 mm. In the second trial, the harvesting was performed by a self-propelled forage harvester (SPFH) at TLOCs of 6, 12 and 18 mm, with a roll gap of 3 mm. The WPCS were stored for 0, 35 and 140 days. In the PTFH trial, the TLOCs of 3 and 6 mm did not affect the WPCS particle size distribution and mean particle length (MPL). However, the TLOC of 9 mm increased the MPL. The increase in the TLOC with the SPFH led to a higher MPL and percentage of long particles. The ensiling time increased the MPL and long particles only for the WPCS harvested by the SPFH. The strategy of reducing the TLOC with the SPFH increased the percentage of kernels smaller than 4.75 mm. Furthermore, the TLOC of 6 mm led to the best kernel processing with the SPFH. The ensiling time reduced the particle size of the kernel fractions for both forage harvesters. The corn silage processing score was improved with 140 days of ensiling with the SPFH. These findings suggest that increasing the ensiling time and a low TLOC in SPFHs (6 mm) may be good strategies to increase kernel damage and starch digestibility in WPCS.