Increasing the Adequacy in Estimation of Dietary Physically Effective Fi-ber could help the Prevention of Sub-Clinical Acidosis in High-Yielding Dairy Cows

Publication Type

Journal contribution

Authors

Zebeli, Q. and Drochner, W.

Year of publication

2006

Published in

Feedinfo (Mai 2006)

Band/Volume

nnb/

Page (from - to)

6 Seiten

Keywords

cow, dairy cows, rumen pH

We quantitatively investigated data from recent research studies to define the physiological re-sponses of dairy cows in early lactation to intake of physically effective fiber (peNDF). All studies were conducted with lactating Holstein cows (84.8 ± 3.54 DIM) in Latin square design and feeds were offered ad libitum as TMR. The peNDF was estimated by two different measurement techniques, namely the NDF content of TMR multiplied by amount of DM retained on a 1.18 mm screen (peNDF>1.18), and NDF content of TMR multiplied by the proportion of DM retained by 19- and 8-mm Penn State Particle Separator (PSPS) screens (peNDF>8). The ruminal pH (day mean) in this study ranged from 5.30 to 6.59. Using peNDF>1.18 approach, the requirements for physically effective fiber in high-yielding dairy cows fed TMR in an ad libitum intake were estimated to be about 19% of ration DM or 4.1 kg/d or 0.6 kg/100 kg BW to maintain a ruminal pH of about 6.0. Results of these data analyses showed that peNDF>1.18 provided a satisfactory estimation of the mean ruminal pH (R2 = 0.67), being an accurate feeding measurement to prevent high-yielding dairy cows from sub-clinical acidosis.