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FORA
GE AND NUTRITION

Guide 20
1
7
FORAGE AND NUTRITION
Guide 2017
20
It is widely recognised that grass-based systems will
predominate in post-quota Ireland and that land will be the
main limiting resource. In more intensive dairying areas,
competition for land is intense. In many cases, a limiting factor
to expansion on these dairy farms is the availability of land
around the milking platform (MP).
Given the significant costs associated with expansion and the
fact that many farmers are operating on a limited land-bank, a
higher input/higher output, spring-calving, grazing system may
prove attractive. Such a system might facilitate the successful
expansion of the farm business without the need to buy or rent
extra land, to buy stock, to acquire extra labour or to provide
extra cow facilities.
The main aim of the research at University College Dublin
(UCD) Lyons Farm is to evaluate the feasibility (including
profitability) of a higher input/output grazing system within
a limited land scenario. The focus in such a system is on
maximising milk/milk solids output from the existing land
holding, which involves high output from individual cows and
high stocking rates on the MP. This will occur most e ciently
through maximising the use of grazed grass/home-grown
forage in the system and the strategic use of supplementation
thereafter.
Targets of the system
The targets (Table 1) in this system involve high milk outputs of
7,500-8,000L and 625kg of fat and protein/cow/lactation using
higher-than-conventional levels of concentrate feed inputs (1.5
tonnes of concentrate per cow per lactation) but with the diet still
mainly grass and grass silage (75 per cent of the feed budget).
The stocking rate on the MP in this system is 3.4 cows per
hectare (ha). Like any other `grass-based system', the principles
of grassland management, appropriate breeding strategies,
fertility and financial management are key to success.
Genetics of the herd
The herd of 60 cows is a high Economic Breeding Index (EBI)
Holstein-Friesian herd (Table 2). Within the herd, a genetic
comparison will be made with one cow group (30 cows) having
a high predicted transmitting ability (PTA) for milk (+250kg) and
one group (30 cows) with a lower PTA for milk (+44kg).
Feed budget
To achieve and sustain high milk and milk solids output along
with good fertility, high energy intakes are essential. Table
3 shows the target feed budget for 2017. High allocations of
concentrates are o ered for the first 120 days of lactation
and drop significantly thereafter. For this research project,
concentrate inputs are fixed and this poses some challenges
in terms of grassland management, especially in springtime.
Concentrate allowances were arrived at by considering the
UFL (unite fouragere de lait) requirements of the cow at each
stage below as well as the expected grass-intake level.
Table 1: Targets for the system.
Parameter
Target
Stocking rate on milking platform
3.4 LU/ha
Stocking rate on whole farm
2.25 LU/ha
Milk yield per cow
7,500-8,000kg
Milk solids per cow
625kg
Six week in calf rate
70 per cent
Concentrate (kg/co/year)
1,500kg
% diet as grazed grass
51
% diet as grazed grass and grass silage 75
Investigating the
potential of a high-
output, spring-calving,
milk-production system
The abolition of the EU milk quota system in 2015 has paved the way to increase cow numbers and milk
output. However, the profitability associated with this extra production for individual farms needs to be
examined and there must be a continuing focus on improving e ciencies
Finbarr Mulligan
University College Dublin
LU Livestock unit