Browsing Journal of Range Management, Volume 40, Number 5 (September 1987) by Subjects
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Influence of Frequency of Drinking on Particulate Passage Rate and Dry Matter Disappearance in Grazing Zebu CattleThree ruminally cannulated zebu steers were used in a water restriction study. Three drinking frequencies were imposed on the steers: watered daily, once in 2 days, and once in 3 days. Particulate rate of passage was estimated by dosing steers with Yb-labeled forage and collecting fecal grab samples for a 5-day period. Steers were grazed from 0700 h to 1800 h, then brought back to drink, and penned overnight. Particulate passage rate decreased (P<0.05) from 3.8 to 2.5 and 2.1%/h, while total mean retention time increased (P<0.01) from 54.0 to 65.2 and 80.2 h for steers watered once daily, once in 2 days, and once in 3 days, respectively. In situ dry matter disappearance in the rumen was increased (P<0.01) and dry matter intake decreased by one-third to two-thirds (P<0.01) by water restriction.
Influence of Watering Frequency on forage Consumption and Steer Performance in Southeastern KenyaForty-five zebu steers (avg wt 311 kg) were allotted to 3 watering frequency treatments with 15 steers/treatment. The treatments involved watering once every day (1/1), watering once every 2 days (1/2) and watering once every 3 days (1/3) to investigate the effect of watering frequency on forage consumption and steer performance. Three steers/treatment were used to quantify fecal output and estimated forage consumption. All steers were grazed together in a 100-ha paddock for 10 hours daily and confined in a corral overnight. Steers were allowed ad libitum access to water only in the evenings according to the watering schedule. The study was conducted over 6 months, during which time total fecal collections were made in March, April, June, and July. All steers were weighed approximately every 2 weeks. Forage consumption was reduced (P<0.01) for steers watering (1/2) and (1/3), compared with the (1/1) watered group. Forage intake was highest (P<0.01) in April when herbage was green and growing. Steer performance followed a seasonal pattern reflecting changes in forage quality. Watering frequency did not influence steer performance. Reducing watering frequency from daily to once ever 2 or 3 days may enhance utilization of available range and save on cost of providing water for cattle under certain pastoral conditions.
Ytterbium-Labeled forage as a Marker for Estimation of Cattle Fecal OutputThis study evaluated the accuracy of a once daily dose of ytterbium (Yb)-labeled forage as a marker to estimate fecal output of cattle grazing at the National Range Research Station, Kiboko, Kenya. Ytterbium-labeled forage was administered daily to 15 zebu steers for 10 consecutive days for each of 3 trials. During the last 5 days of each trial, fecal grab samples were collected at 6-h intervals. During this same 5-day period, total fecal output was collected from 9 of the steers. Ytterbium estimates of fecal output were 114%, 104%, and 144% of actual fecal output for March, April, and July trials, respectively. Dry matter and organic matter intake estimates between Yb and total collection procedures differed (P<.05) in the July trial, but not the March and April trials. Compared with total fecal collection, Yb overestimated organic matter intake by 20, 2, and 40%, respectively for March, April and July trials. Based on our results, daily dosing of Yb-labeled forage will provide reasonable estimates of fecal output when relative estimates of intake between range management treatments are needed.