Fifteen Holstein cows, 35 to 70 d postpartum, were assigned to five 3 x 3 Latin squares. Treatments were: control (60% concentrate, 40% corn silage, DM basis) or control supplemented with either .71% sodium bicarbonate or .65% sodium sesquicarbonate, DM basis. Orthogonal contrasts compared the effect of both buffered diets versus the control diet, and the effect of sodium bicarbonate supplementation vs. sodium sesquicarbonate supplementation. There were no differences among treatments for milk yield (34.9 kg/d), milk fat yield (.99 kg/d), 3.5% FCM (31.1 kg/d), or milk protein concentration (3.15%). There were no treatment effects on total chewing time. Milk fat concentration tended to be greater for cows fed sodium bicarbonate (2.92%) and sodium sesquicarbonate (2.89%) relative to control (2.82%). Relative to control, sodium bicarbonate and sodium sesquicarbonate supplementation increased DM intake (22.0 and 22.7 vs. 21.4 kg/d), digestible DM intake (16.7 and 16.2 vs. 14.8 kg/d), digestible organic matter intake (16.0 and 15.5 vs. 14.3 kg/d); and apparent digestibility of DM (77.3 and 74.8 vs. 73.3%) and NDF (62.6 and 56.5 vs. 54.7%). Relative to sesquicarbonate, bicarbonate supplementation increased apparent digestibilities of CP (82.3 vs. 78.8%) and NDF, and decreased milk protein yield (1.06 vs. 1.11 kg/d). Sesquicarbonate was as effective as bicarbonate in alleviating milk fat depression and increasing intake of digestible organic matter.

In two experiments, we studied the characteristics of ensiling and aerobic stability of triticale (x Triticosecale spp.) ensiled with or without a homolactic bacterial inoculant (HBI). The first experiment used 60 vacuum-sealed 0.946 L glass jar mini-silos (GJ) to determine the effect of ensiling on pH, dry matter recovery (DMR) and temperature. Three GJ per treatment were opened on d 0, 1, 2, 3, 5, 7, 14, 30, 105 and 123 of fermentation. Across all lengths of fermentation, inoculation decreased (P<0.05) average silage pH and temperature upon opening the mini-silos but did not influence (P>0.05) DMR versus the Non-HBI silage. Both silages had a similar (P>0.05) pH at the end of 123 d of fermentation. The second experiment compared the nutritional and fermentation characteristics and aerobic stability of triticale ensiled with or without HBI for 123 d in either 3L PVC mini-silos packed manually (PVC) or vacuum-sealed GJ. There was little difference (P>0.05) in silage nutrient content using PVC or GJ mini-silos, nor did inoculation affect these variables. Ensiling triticale decreased (P<0.05) its 30 h neutral detergent fiber (NDF) digestibility, the lowest value being that of Non-HBI/ PVC silage, which differed (P<0.05) from the HBI/PVC silage, but these did not differ (P>0.05) from the GJ silages. Differences among silages were not found (P>0.05) in NDF at 240 h (uNDF240), total tract NDF digestion (TTNDFD) and rate of NDF digestion (NDFkd). Triticale ensiled well in GJ, however the amount of material ensiled may have been too small to detect differences due to inoculation.

Three Latin-square trials were conducted to determine the effects of supplementing Rumen-Mate, a commercial buffer containing KCl, NaCl, and Mg and Na carbonates, on lactation performance of Holsteins. Cows were fed a basal ration of 40% corn silage and 60% concentrate in Trials 1 and 2, and 40% corn silage, 55% concentrate, and 5% alfalfa hay in Trial 3 (DM basis). In Trial 1, treatments were: basal diet, or basal diet supplemented with either 1% NaHCO3, or 1, 3, or 4.4% Rumen-Mate. Increasing dietary Rumen-Mate resulted in a linear increase in milk fat production and concentration with no difference between 1% Rumen-Mate and 1% bicarbonate. There was a significant linear decrease in milk protein concentration, but not production, with increasing concentrations of Rumen-Mate. In Trial 2 treatments were: basal diet, or basal diet supplemented with either .8% NaHCO3, 2.6% Rumen-Mate, .5% MgO, .8% NaHCO3 plus .5% MgO, or 1.8% Rumen-Mate plus .8% NaHCO3. Organic matter and CP intakes and milk protein yield and concentration were decreased by Rumen-Mate with a nonsignificant increase in milk fat concentration. Data from Trials 1 and 2 were combined with data from Trial 3, which compared basal diet, 1% bicarbonate, and 3% Rumen-Mate. The combined data showed a larger increase over basal diet in milk fat yield and concentration for 2.6 to 3% Rumen-Mate vs. .8 to 1% bicarbonate. Rumen-Mate did not decrease DM intake or protein yield relative to basal diet but did decrease protein yield 34 g/d compared with that of bicarbonate.

Fresh whole plant spring triticale (x Triticosecale spp.) was field wilted and chopped prior to either being sprayed or not with a homolactic bacterial inoculant (HBI). Wilted triticale was ensiled for 120 d at 20 to 23 °C using 16 PVC mini-silos of 3 L capacity fitted with two-way mechanics to vent gas (which imposed aerobic stress (ASTS) when it remained open), and filled with about 2 kg of the crop containing 35% dry matter (DM) and 5.2% water soluble carbohydrates (WSC) in the DM. Four treatments of a 2x2 factorial were: 1) No HBI/vent closed; 2) HBI/ vent closed; 3) No HBI/vent open; 4) HBI/vent open. Upon opening the mini-silos, chemical composition, fermentation characteristics and in vitro 30 h neutral detergent fiber (NDF) digestibility of the silages were determined. Relative to pre-ensiled forage, either sprayed or not with HBI, ensiling increased (P<0.05) contents of moisture, inorganic matter, fibrous fractions (acid detergent fiber (ADF) and lignin), and ether extract (EE), while decreasing contents of WSC and non-fibrous carbohydrates (NFC). However, treatment had no consistent effect on content of silage nutrients. Of the two non-inoculated silages, the one subjected to ASTS was more than 20 percentage points lower (66 vs. 88 %) in DM recovery (DMR), whereas the HBI silage subjected to ASTS was protected from DM losses. Ensiling and ASTS during the 120 d fermentation decreased NDF digestibility, whereas inoculated non-ASTS silage was nearly as digestible (57.5) as the pre-ensiled forages (58.2 and 60.7%, without and with HBI). Inoculation tended to steer fermentation in a homolactic direction. On balance, HBI is recommended because of the benefits in the fermentation pattern, fiber digestibility and DMR, especially in the presence of ASTS.

Triticale (x Triticosecale spp.) silage initially inoculated or not with homolactic bacteria (HBI) was stored in 3 L capacity PVC mini-silos for 120 d. After opening four mini-silos per treatment, silages were mixed and exposed to air (AE) for 5 h. Then half of the non-inoculated silage and half of the inoculated silage were re-treated with a water soluble HBI or water, thus resulting in four combinations of experimental treatments (initial ensiling/re-ensiling): 1) noninoculated/ non-inoculated (N/N); 2) non-inoculated/HBI (N/HBI); 3) HBI/noninoculated (HBI/N); 4) inoculated/inoculated (HBI/HBI). Silages were re-ensiled for 120 d at a temperature of 20 to 23° C using four vacuum sealed, 0.946 L capacity glass mini-silos per treatment. Upon opening the mini-silos, silages were sampled and analyzed for nutritional and fermentation characteristics and aerobic stability (AS). Inoculation at the initial ensiling (treatments HBI/N and HBI/HBI) was key in preserving the protein fraction and improving fiber digestibility, while decreasing the pH and contents of fiber fractions, NH3-N and ethanol. The resulting silages were all aerobically stable and there were no differences among treatments. The benefits of inoculating at the initial ensiling carried through re-ensiling. Inoculation at re-ensiling was neither beneficial nor detrimental to any of the characteristics evaluated.