Effect of increased concentrate allotment before evening grazing on herbage intake, nitrogen utilization and rumen fermentation in dairy cows grazed on perennial ryegrass pasture

Abstract

Two experiments were conducted to elucidate the effect of increased concentrate allotment before evening grazing on herbage intake, nitrogen utilization and rumen fermentation in dairy cows. In experiment 1, nine lactating cows were grazed in the morning and evening sessions (2.5 h each). The cows were allocated to treatments of three concentrate allotment levels before the evening grazing session by altering proportions to daily total offered; 25%, 50% and 75%. Daily herbage dry matter intake quadratically decreased with increasing the concentrate allotment levels (P < 0.05). Nitrogen utilization was similar among treatments. To investigate diurnal changes in rumen fermentation, a second experiment was conducted where six ruminally cannulated non-lactating dairy cows grazed in the morning and evening sessions (3 h each) were subjected to the same treatments as experiment 1. Total volatile fatty acid concentration in the rumen linearly increased with increasing the concentrate allotment levels throughout the pre-evening grazing session to the post-morning grazing session (P < 0.01). The results indicate that dairy cows reduce daily herbage intake but do not alter nitrogen utilization with increasing concentrate allotment before evening grazing. © 2016 Japanese Society of Animal Science.

Effects of grazing adaptation on intake, ruminal fermentation, blood metabolites, and body weight change in dairy cows after turning out to pasture in early spring

“…Herbage DM intake during the adaptation and experimental periods was measured using the double‐indicator method, using the lanthanum (La) maker as an external marker and C 33 alkane as an internal marker (Ueda et al., 2016a). The La maker was prepared by soaking the LaCl 3 ‐7H 2 O solution into sugar beet‐pulp.…”

“…Feeding time of herbage (min/day) was measured using the Kenz Lifecorder EX (Suzuken Co. Ltd., Nagoya, Japan) according to the method described by Ueda et al (2011) Herbage DM intake during the adaptation and experimental periods was measured using the double-indicator method, using the lanthanum (La) maker as an external marker and C 33 alkane as an internal marker (Ueda et al, 2016a). The La maker was prepared by soaking the LaCl 3 -7H 2 O solution into sugar beet-pulp.…”

Threshold Rangeland Condition for Rangeland Restoration Investments and the Financial Equivalent of Liveweight Losses Due to Rangeland Degradation

“…As seen in Fig. 3 Ueda et al, 2016). Due to abundant rangeland forage allowance during humid season and especially in June-August period, concentrate supplementation did not increase total digestible dry matter intake.…”

Effects of Type of Concentrate and Timing of Supplementation on Feed Intake, Nitrogen Use, and Performance in Lactating Dairy Cows Grazing an Alfalfa-Ryegrass Sward

“…For instance, the extent and rate of ruminal degradation of starch from oat or wheat differ from that of corn or rice depending on starch granule size, its degree of crystallization, and amylose to amylopectin ratio, among other factors [11,12]. Moreover, synchronizing the amount and time of energy and N supply to rumen microorganisms is considered to maximize the efficiency of microbial protein synthesis (EMPS), and thus the use of CP degradation products in the rumen [13,14], while reducing their ruminal absorption and excretion via urine. Hence, the effects of feeding different types of cereal grains may differ depending on the time when they are offered.…”