field observations of ten dairy herds in
Nebraska during the summer of 1997
(Grant and Albright, 1997), in most cases,
farms with the highest dry matter intake
and productivity had alleys of sufficient
width so that two cows could walk com-
fortably in opposite directions behind the
row of cows standing and eating at the feed
line. With insufficient space, either from
poor barn design or overcrowding a group
of cows, normal movement of cows in the
alley behind the feed manger disrupted
eating activity, precipitated fights and
interfered with intense, focused feeding
activity. Many free stall barns designed
today in the USA provide floor space of
approximately 3.7–5.1 m^2 per cow, exclud-
ing free stall and drinking areas. The alley
between the feeding line and the first row
of free stalls should be at least 4.3 m wide
to allow comfortable cow movement and
avoid interference with aggressive, focused
feeding activity.
Feed bunk or manger designMany dairies use fenceline feeding systems
in which cows eat with their heads in a
natural grazing position. Evidence exists
that cows eating with their heads in a
downward position secrete 17% more
saliva than cows eating with their heads
held horizontally, which could result in
better ruminal function (Albright, 1993).
Concrete mangers that have been
renovated with epoxy finishes, wood or
tiles aid feed consumption. Over time,
lower pH silages can etch and pit concrete,
which exposes the cow’s tongue and mouth
to rough and sharp edges.
Cows exhibit more rooting behaviour
in shallow, elevated feed bunks or troughs.
Albright (1993) observed lactating dairy
cows once weekly for feed tossing
behaviour when they were fed TMR.
Approximately 10% of the cows observed
participated in this behaviour. The amount
of feed wasted was 0–5% each week. Feed
tossing was especially prevalent in summer
during heavy fly concentrations, but
occurred in winter as well. When given the
choice of eating from an elevated bunk
with the floor either 28 or 76 cm from
ground level, or from the same trough at
ground level, cows chose the lower level.
Also, the group fed at ground level
exhibited no feed tossing behaviour. It374 R.J. Grant and J.L. Albright
Fig. 17.3.Separate grouping of primiparous dairy cows results in greater feed intake.