The objectives of this study were to evaluate the effect of differences in protein type and delivery method on rumen dynamics and nutrient digestion. Cows were allotted to rumen degradable protein (RDP) or rumen undegradable protein (RUP) and self-fed (SF) salt-limited pressed blocks or hand-fed (HF) loose supplement, resulting in four dietary treatments. There was a delivery effect (p = 0.04) on neutral detergent fiber (NDF) intake, as the SF animals consumed more NDF than HF animals. The RDP-SF animals had greater NDF digestibility (p = 0.04) and water intake (p = 0.03) than the three other treatments. Supplement intake displayed a protein type effect (p = 0.03), as RDP-supplemented animals consumed more supplement on a g·kg body weight (BW)−1 d−1 basis than RUP animals. There was an effect of protein type (p = 0.02) and delivery method (p = 0.03) on fluid flow rate, with RUP and HF cows having greater liquid flow rates. Ruminal pH was lower (p < 0.01) in RDP-HF cows than RDP-SF cows at all hours, except 4-h post-feeding. RDP-SF animals had the greatest (p < 0.01) concentrations of ruminal ammonia. Valerate ruminal concentrations were greater (p = 0.04) in RDP supplemented animals compared to RUP supplemented animals. In conclusion, self-fed supplements containing RDP may enhance the use of low-quality forages and increase ruminal ammonia concentrations.

Angus and Red Angus-based yearling heifers (n = 40) and lactating cows (n = 51) were each used in a complete randomized design and stratified by weight and body condition score to one of two treatments: (1) pressed supplement block containing rumen undegradable protein (RUP) and (2) pressed supplement block containing rumen degradable protein (RDP). Heifer and cow supplement intake displayed (p < 0.01) a treatment × period interaction. The RUP heifers and RDP cows consumed more in Period 2 than Period 1, whereas RDP heifers and RUP cows consumed more in Period 1 than Period 2, respectively. Intake rate demonstrated (p < 0.01) a treatment effect for heifers, with RUP consuming supplement faster than the RDP treatment. Intake rate for cows demonstrated (p < 0.01) a treatment × period interaction with RUP cows in Period 1 having faster intakes than Period 2, and RDP cows having the inverse. Cow intake variation displayed (p < 0.01) a treatment × period interaction with RUP cows having more variation in Period 2, while RDP cows had less variation in intake in Period 2. In conclusion, RDP and RUP impacted intake behavior of cows and heifers but had minimal impacts on performance.

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The objective of this project was to determine if sugar beets could be ensiled with hay or soybean meal with or without a liquid mold inhibitor and the impact on nutrient composition, pH, and aerobic stability. A 3 x 2 factorial experiment where hay (control; H) or sugar beets mixed with either hay (SBH) or soybean meal (SB) were ensiled at a rate of 50:50 (as fed) without the mold inhibitor. The mold inhibitor (T) was included to create three additional treatments: HT, SBT, and SBHT. All treatments decreased in pH over time (P < 0.01), with the lowest pH value being generated by the SB treatment. Concentrations of NDF increased between d 0 and d 90 for treatments SB and SBT (P ≤ 0.01) and increased between d 90 and d 180 for treatments H, HT, SBH, and SBHT (P ≤ 0.01). Concentrations of ADF also increased among all treatments (P ≤ 0.05). Concentrations of CP increased from d 0 to d 90 for HT and SB treatments (P ≤ 0.01), increased from d 90 to d 180 for the SBT treatment (P ≤ 0.02), increased from d 0 to d 180 for the SBH treatment (P ≤ 0.03), and decreased from d 90 to d 180 for the SB treatment (P ≤ 0.01). The data suggests that sugar beets may be ensiled with hay or soybean meal, with or without a liquid mold inhibitor, without negatively impacting nutrient quality or preservation characteristics of the ensiled mixture.