Cattle grazing preference among eight endophyte-free tall fescue cultivars

Shewmaker, Glenn E. and Mayland, Henry F. and Hansen, Susie B. (1997) Cattle grazing preference among eight endophyte-free tall fescue cultivars. Agronomy Journal. 89:695-701.

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Abstract

`HiMag' tall fescue (Festuca arundinacea Schreb.) was selected
for high Mg concentration to reduce grass tetany risk to ruminants,
but neither animal preference nor consumption of HiMag were known.
The objectives were to evaluate methods of quantifying preference
and to determine intake and preference by cattle (Bos taurus L.) of
HiMag relative to seven other tall fescues. All entries were free of a
fungal endophyte [Neotyphodium coenophialum (Morgan-Jones &
Gams) Glen, Bacon & Hanna] that reduces cattle performance. The
experimental design was a randomized complete block with three
replications of eight cultivars nested within each of three test pastures.
Six heifers grazed the vegetative to boot-stage pastures for 48 h in
May, June, August, and September of 1993 and 1994. The pastures,
located at 1200 m elevation, were furrow irrigated. Pre- and post-grazed
forage were clipped and weighed to determine yield and utilization
(48-h utilization < 50%). Preference scoring of 0 to 10 (0 to 100%
of forage eaten) was done by four trained observers at 24, 30, and
48 h. The heifers quickly learned to distinguish between cultivars, and
their order of preference was Kenhy > KY 31 > HiMag = Barcel =
Cl = Stargrazer > M096 = Mozark. The cultivar x trial(year) interaction
for preference indicated that cultivars responded differently
to weather conditions, which in turn affected animal preference. Preference
scoring had high repeatability and ranked cultivars similarly
to the clip-and-weigh method of measuring utilization. Preference
scoring was accomplished with 27% of the experimental error and
only 6% of the time required for clip-and-weigh. Only 44% of the
variation in preference score (PS) was explained by the model: PS =
8.8 - 1.1(Mg DM yield ha-1). Estimated dry matter (DM) intake of
HiMag was 6.4 kg (animal unit day)-1. Consumption and preference of
HiMag by cattle are satisfactory relative to other tall fescue cultivars.

Item Type:	Article
NWISRL Publication Number:	0945
Subjects:	Animal > Feed preference Irrigated crops > Grass forage > Animal preference Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:54
Last Modified:	21 Nov 2016 20:34
Item ID:	682
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/682