The Rural Voice, 1995-08, Page 48Advice/pasture management
A leader -follower
grazing system for
sheep
BY JIM JOHNSTON
AND MARK LENOVER
NEW LISKEARD
AGRICULTURAL
RESEARCH STATION
A leader -follower grazing system
(also called forward grazing) can be
used when groups of animals with
different nutrient requirements are
being pastured on the same farm.
Two groups of animals, leaders and
followers, are formed. The leader
group consists of animals with
relatively high nutrient requirements
and the follower group consists of
animals with relatively low nutrient
requirements.
The system utilizes an existing
rotational grazing set-up. Each
paddock is grazed initially by the
leader group. They remove the
highest quality herbage from the
paddock and are then moved to a
fresh paddock. The follower group is
then moved into the first paddock to
graze the forage that the leader group
left behind. This forage tends to be
of lower quality, but should be
sufficient to meet the nutrient
requirements of the stock in the
follower group.
The length of time that each group
is left to graze a particular paddock
will vary with pasture quality and
yield, the nutrient requirements of
the stock in each group, and the
performance goals the pasture
manager sets for the livestock.
Methods
The leader -follower principle was
used with two groups of sheep at
New Liskeard in 1994. The leader
group consisted of 37 lactating ewes
and 74 lambs. The ewes were mostly
three-way crosses containing
Romanov, Dorsett, and Suffolk.
Lambs were born in early May. The
follower group consisted of 58 dry,
open ewes. These ewes were
Dorsett -Suffolk crosses whose lambs
were weaned in early May. The
object of the trial was to graze the
two groups in a leader -follower
system to achieve acceptable lamb
gains while preventing the dry ewes
from getting excessively fat.
Paddocks of about 0.4 ha were
grazed for up to four days by the
leaders and seven days by the
followers. Paddocks were topclipped
once during June or July after the
followers had been removed. In
total, the pasture carried 11.9 ewes
and 9.3 lambs per acre during the
approximately two month
demonstration.
Results
Over a 66 -day test period, lambs
in the leader group gained 236 grams
per head per day, while the ewes in
the leader group lost about 90 grams
per head per day (Table 1). Some
weight loss in early lactation ewes is
normal, although the weight loss here
was greater than desired. It seems
that once the pasture began to
mature, the leader group could not
select enough high quality material to
maintain ewe body weight, although
lamb gains were acceptable.
The follower group grazed the
experimental pasture for 43 days.
During that time, ewes in the
follower group lost 69 grams per
head per day and about 0.3 points of
body condition score (BCS, Table 2).
Table 1. Performance of ewes and lambs in leader group.
Lamb ADG
Ewe Weight Change
Ewe BCS Change
236 grams/head/day
-92 g/hd/day
-0.1
Table 2. Performance of dry ewes in follower group.
Dry Ewe Weight Change
Ewe BCS Change
-69 grams/head/day -
-0.3
44 THE RURAL VOICE
Considering the pasture "clean up"
role these ewes were in and their
good condition at the start of the trial
(BCS=3.4), the weight loss during
the trial is not surprising.
Summary
This demonstration showed the
potential for leader -follower grazing
systems. The pasture was beginning
to mature by the time the demonstra-
tion started, thus the leader group had
trouble selecting very high quality
forage. Lamb gains were acceptable,
but some of the lamb gain was at the
expense of ewe weight loss. The
follower group cleaned up the mature
forage well, utilizing what otherwise
would have been wasted forage.
Weight loss in the follower group
was not excessive and the dry ewes
were easily brought into breeding
condition later in the year.0
Managing your
pastures intensively
to manage fertility
BY SCOTT BANKS
PASTURE ADVISOR
Grazing livestock recycle varying
portions of the nutrients that they
consume back to the pasture via their
manure, therefore grazing
management greatly affects the
nitrogen, phosphorus and potassium
fertility level of the pastures. Some
of the aspects of Grazing
Management that affect fertility are
the size and shape of paddocks, the
grazing frequency, stocking rates and
the location of shade and livestock
watering sources. All these factors
alter the pasture's fertility due to the
pattern and concentration of where
livestock manure. Dr. Gerrish and
Dr. Peterson from the University of
Missouri looked at the effect of the
location of watering sources and
shade and the paddock design and
grazing frequency on pasture fertility.
Dr. Gerrish found that fertility levels
changed based on the cattle's
preferred grazing pattern and water
and loafing areas.
Locating water sources in
laneways as compared to having a
water source in each paddock, has the