appears that the optimally constructed feed
bunk or manger is at a height that allows
cows to consume feed in a natural grazing
position. Although rare, feed tossing
behaviour can still occur with cows in self-
locking stanchions with their heads in the
head down position (Fig. 17.4).
Data summarized by Albright (1993)
indicated that the floor of the feed trough
should be level or slope no more than 1%
along the length of the feed bunk. When
mangers have slopes of >3–5%, cows shift
and move in the direction of the slope.
This movement is continual and interferes
with feeding activity.
Feed barrier design: restraint with headlocksAs part of a regional dairy management
research project in the USA, scientists at
Purdue University and Utah State
University evaluated the effect of extended
lock-up times on cow behaviour, well-
being and productivity. Self-locking
stanchions (headlocks) are used commonly
in commercial dairies (Fig. 17.5) to restrain
cattle for various management tasks such
as: (i) artificial insemination; (ii) pregnancy
checking; (iii) monitoring herd health; and
(iv) top-dressing a supplement (Fig. 17.6).
This system of restraining animals in the
feeding area can be abused, and thus
compromise cow comfort, when cows are
allowed to remain in the headlocks beyond
the period of time actually necessary for
the management routine.
To investigate the effect of restraint
using self-locking stanchions, 64 Holstein
cows from peak to end of lactation were
restrained in these stanchions for approxi-
mately 4 h day^1 for four periods in a
modified switchback design (Bolinger et
al., 1997). Milk production, somatic cell
count and total daily feed intake were
unaffected by the restraint. Behaviourally,
cows that were locked up spent significantly
more time lying down after release from
restraint. For cows that were locked in
stanchions, eating frequency over 24 h was
significantly reduced, but dry matter intake
was not affected. Total rumination frequency
over 24 h was not affected, but restrained
cows ruminated less during the following
day. Grooming was significantly increased
during all times that cows were not locked
up, and was considered to be a behavioural
need. Grooming was also one of the first
behaviours performed following release.
Acts of aggression were elevated during all
periods following restraint. Although the
proper use of self-locking stanchions for
restraint does not seem substantially to
affect the overall well-being of the cow,
there appears to be some potential to
impact feeding and ruminating behaviour
adversely.Feed barrier design: slope and pressure
exerted during feedingFeed barriers and mangers should provide
free access to feed without risk of injury or
discomfort. Feed mangers or barriers
should also allow undisturbed feeding
activity and minimize feed wastage.
Additionally, cows can be restrained by
some feed barriers such as self-locking
stanchions. A relationship may exist
between the layout of the feeding area,
particularly feed barrier design, and the
number of injuries for cattle. The barrier
between the cows and their feed is often
constructed in such a way that cows press
hard against the barrier when attempting to
reach their feed, thereby increasing the risk
of injury or discomfort.
A well-designed feeding system should
result in cows needing to exert the lowest
pressure against the feeding barrier while
consuming feed. Pressures of <500 N have
no effect on the cow, pressures of
500–1000 N may cause harm, and pressures
>1000 N may cause acute damage (Hansen
and Pallesen, 1998). Hansen and Pallesen
(1998) evaluated the effect of the pressure
exerted by dairy cows on self-locking
feeders on feeding activity and cow com-
fort. Measurements taken during both day
and night showed that >80% of the
pressure occurred within the first hour
after feeding. Peaks in pressure applied to
the feed barrier occurred when remainingFeeding Behaviour 375