| Grassland
says Sarah Pick, scientific officer
at AHDB Beef & Lamb. The first
step is to plan the grazing season:
Calculate how much grass is
available, set up a rotation and
keep a close eye on grass growth
rates. “Identify which fields are
producing the most grass and
coincide your rotation with that.
Good infrastructure will ease
management.”
It is also important to calculate
how many cattle the grazing
platform can support. While mid-
pregnancy cows need to be
allocated 1.5% of their body
weight in dry matter intake per
day, late lactation cows should eat
2% of their body weight. Early to
mid-lactation cows need 2.5% and
growing cattle should have 3% per
day. An average weight, number of
stock in the group and area
available need to be used as part
of the calculation to plan stocking.
The ideal time to turn stock out
is when pasture reaches
2,500kg/ha of dry matter; around
ankle height, says Miss Pick.
“When grass grows past this,
utilisation and feed quality drops
rapidly.” Ideally, farmers should
then take this pasture out of the
rotation and shut it up for silage.
Cows should graze down to
about 1,500kg DM/ha (around 4
cm), and be moved to fresh
pasture at regular intervals. If there
is too little grass, cattle will be
forced to eat lower, which will
prevent regrowth, so farmers
should consider supplementary
feeding where grass growth is
insufficient.
Nutrition is key both to grass
growth and quality, and the revised
RB209 nutrient guide is being
released at Grassland & Muck to
help farmers get the most out of
farmyard manure and slurries,
says Miss Pick. “As a guide, the
maximum usage of nitrogen for
grass silage is 2.5kg/day of active
growth, so 50 days between
application and cutting would
require 125kg/ha of N.”
Prize-winning grass varieties boost productivity
and reduce environmental impact of agriculture
IBERS develops new grass varieties that require less
fertiliser, improve production per animal, and improve the
efficiency with which ruminant animals utilise the nitrogen
in their diets.
mproving the
sugar content in
grasses results in
improved
efficiency of plant
protein
conversion, providing an
economic benefit to farmers
through improved feed conversion
and an environmental benefit
through reduced nitrogen
pollution.
More than ten high sugar
perennial ryegrass varieties have
been produced by IBERS,
including AberGreen, AberZeus,
AberBite, AberChoice, AberSweet,
AberMagic, AberStar, AberDart,
AberAvon and AberZest and a
hybrid ryegrass AberEcho, all of
which have been successfully
added to recommended lists in UK
and elsewhere in the world.
In 2015 AberGreen was the
winner of the NIAB Variety Cup. In
I
www.farmingmonthly.co.uk
addition, five further varieties have
been entered into UK national list
tria ls. A partnership between
IBERS and Germinal Holdings, the
UK owned forage and grass seed
production and wholesale
marketing and distribution
company, has enabled these
varieties to be made widely
available to all UK farmers.
The impact of high sugar
grasses on the livestock sector
has been significant. High sugar
ryegrass varieties bred at IBERS
have been shown to increase milk
production by up to 6% more milk
per cow over grazing season, and
for beef, contribute to a 18-35%
higher daily live weight gain. In the
lamb sector, high sugar grasses
have led to a 10-15% higher daily
live weight gains with a 20% higher
carrying capacity of swards
containing the HSG varieties.
May 2017 | Farming Monthly | 27