Publication Database

Effect of the forage-to-concentrate ratio on DMI and ruminal fermentation based on timing of feeding relative to feed restriction (2012)

Art

Vortrag

Autoren

Albornoz, R.I.

Aschenbach, Jörg R. (WE 2)

Barreda, D.R.

Penner, G. B.

Kongress

JAM 2012 Animal Meeting

Arizona, 17.07.2012

Quelle

Animal science

Bandzählung: 90

Heftzählung: Suppl. 3

Seiten: 478

ISSN: 1357-7298

Sprache

Englisch

Kontakt

Institut für Veterinär-Physiologie

Oertzenweg 19 b
14163 Berlin
+49 30 838 62600
physiologie@vetmed.fu-berlin.de

Abstract / Zusammenfassung

The objective of this study was to evaluate the interaction between
the forage-to-concentrate ratio (F:C) of diets fed before (baseline) and
during short-term feed restriction (FR; collectively denoted as PRE) and
those fed post-feed restriction (POST) on DMI and rumen fermentation.
Twenty ruminally cannulated heifers (477 ± 38 kg BW) were exposed
to 14 d for adaptation followed by 5 experimental periods; 5-d baseline,
5-d FR, and 3 wk of recovery (R1, R2, and R3). Heifers were fed, ad
libitum, a high forage diet (HF; F:C = 92:8) or a moderate forage diet
(MF; F:C = 60:40) during baseline, and FR was imposed at 25% of
ad libitum DMI. During recovery, one half of the HF and MF heifers
remained on the same diet, and the other half were exposed to an abrupt
switch (e.g., HF/HF, HF/MF, MF/HF, and MF/MF). PRE × period (
P= 0.02) and POST × period (
P= 0.04) interactions were detected for
DMI. Although DMI, within periods, was not different for HF and MF,
heifers fed HF PRE increased DMI from R1 to R3. Heifers fed HF POST
had higher intake during R1 than heifers fed MF with no differences
observed between diets within other periods. A PRE × POST × period
interaction was detected for butyrate concentration (
P= 0.01). Butyrate
was higher for cows fed MF PRE than HF PRE. Butyrate concentration
decreased from baseline to FR and returned to baseline values by R3;
although the extent of the increase was greater for heifers fed HF PRE
than MF PRE. PRE × period (P= 0.02) and POST × period (
P< 0.01)interactions were detected for mean pH. For the PRE × period interac
-tion, heifers fed HF had higher pH than those fed MF during baseline,
but pH did not differ between diets during FR. Despite this, pH was
higher during FR than baseline and decreased for all heifers during R1
with mean pH returning to baseline values by R2 for HF heifers. For
the POST × period interaction, mean pH during R1 was lower for MF
than HF, but no other differences were detected among treatments. This
study indicates that feeding MF before, and HF after FR reduces risk
for ruminal acidosis following FR