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.

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.

This study aimed to evaluate commercially purified essential oil compounds to assess molecule-specific effects when applied as additives to rehydrated corn grain silage (RCGS). Dry ground corn grains were rehydrated to 350 g/kg moisture and packed (>1,000 kg/m3) in 5-L plastic buckets. Treatments were prepared as a factorial arrangement of two storage lenghts (30 and 60 d) × fifteen strategies (compound × application rate), being: control RCGS; carvacrol at 200, 600 and 1,000 mg/kg fresh matter (FM); cinnamaldehyde at [...] ABSTRACT This study aimed to evaluate commercially purified essential oil compounds to assess molecule-specific effects when applied as additives to rehydrated corn grain silage (RCGS). Dry ground corn grains were rehydrated to 350 g/kg moisture and packed (>1,000 kg/m3) in 5-L plastic buckets. Treatments were prepared as a factorial arrangement of two storage lenghts (30 and 60 d) × fifteen strategies (compound × application rate), being: control RCGS; carvacrol at 200, 600 and 1,000 mg/kg fresh matter (FM); cinnamaldehyde at

Tropical climates present environmental challenges to the stability of total mixed ration (TMR) in the feed bunk throughout the day. Increasing feeding frequency is a typical suggested strategy to compensate for TMR deterioration and to prevent refusal by animals. However, treatment with a propionic acid-based additive could stabilize the TMR enough to allow a reduction in daily feeding frequency. In the preliminary laboratory trial, the additive improved the aerobic stability of TMR, and the optimal dose of 2 mL/kg of fresh matter (FM) was selected for the Additive strategy in the subsequent animal performance trial. Twelve Holstein cows (mean ± standard deviation; 612 ± 158 kg of body weight, 27 ± 6.5 kg/d milk yield, 178 ± 60 days in milk, and 3.0 ± 0.5 of body condition score) were assigned to a switch-back design to evaluate the effect of two feeding management strategies: Control, with two daily feeding of a control TMR; and Additive, with cows receiving a single daily feeding of a TMR treated with the additive at 2 L/t FM. The TMR was composed of 446 g/kg of dry matter (DM) corn silage, 64.0 g/kg DM Tifton haylage, 211 g/kg DM rehydrated corn grain silage, 163 g/kg DM soybean meal, 92.5 g/kg DM citrus pulp, and 23.2 g/kg DM mineral-vitamin mix. Cows fed the Additive strategy significantly increased daily milk yield by 10.2% without changes in DM intake, although no difference was observed for the feed efficiency. Milk contents of total solids and fat were decreased for cows in the Additive strategy. An increase in somatic cell count was observed for cows in the Additive, which could be related to the faster first meal activity after milking than the cows in the Control strategy, rendering them more susceptible to teat contamination. Milk energy and milk urea nitrogen contents were not affected by treatments, although energy excretion through milk was greater for the cows in the Additive. The Additive strategy promoted a shift in the sorting behavior in favor of longer particles, increasing the time spent on rumination, and decreased the number of daily meals at the expense of larger meal size. Two contemporary trials were conducted to measure changes in the thermal and hygienic behavior of the experimental TMR offered in the animal performance trial, simulating aerobic exposure for a 24-h period in exclusive feed bunks installed in the free stall barn, without animal access. The Control TMR presented shorter aerobic stability for the middle and top layers in the feed bunk compared to the bottom layer, while the Additive TMR presented no differences across layers, suggesting a generalized microbial activity suppression independent of the protective effect of upper layers. The Additive TMR suppressed yeasts survival persistence and their activity. Our results suggest that treating TMR with the additive improves the maintenance of its hygienic and thermal profile in the feed bunk, which enables the strategy of a single daily feeding with significant benefits in animal performance.