An investigation into the validity of some of the pasture and veld norms used in budget feed programmes in the Underberg district
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Date
1978-10
Authors
Du Plessis, Thomas Marius
Journal Title
Journal ISSN
Volume Title
Publisher
University of the Free State
Abstract
Underberg lies immediately to the east of and below the
Drakensberg, which is a mountain range in the province of
Natal of the Republic of South Africa.
The agriculture extension area is comprised of 200
farms, which on an average are 800 hectares in extent.
As a result of an active study group, which for the
years 1953 to 1970 kept accurate economic figures, the main
cost items on the farm were found to be fertilizer, bought
feed, repairs, labour and fuel cost. The extension workers
decided to help the farmers by trying to cut the bought feed
costs. To this end the idea of budget feeding was introduced
and put into practice by the extension workers. Budget
feeding was the name given to the plan, which assisted the
farmer in calculating the necessary feed required to feed his
animals for the 355 days of the year. Knowing the amount of
feed required, norms of quantity and quality were applied to
the budget feed exercise, leading to the number of hectares
of each crop that should be grown.
Over a five year period budget feeding was carried out
in the Underberg district. The plan was moderately successful.
However, there were a number of farmers that were disappointed
with the plan, in that they apparently carried out the budget
feed plan, but still ran short of feed towards the end of
winter.
A check was made on the factors that could lead to a
budget feed shortcoming. An evaluation on the check points
showed that there were some limiting factors, which possibly
could hamper the success of an Underberg budget feed plan.
2. It was decided to investigate the limiting factors in
more detail, and to this effect the following trials were
undertaken.
A comparison of the productivity of eight existing farm
pastures was undertaken under topland irrigated, topland non-irrigated
and lowland non-irrigated conditions.
The dry matter yields of the eight types of pasture varied
enormously from the dry matter yield norms used in the
budget feed exercise. The actual yield of fescue was
approximately thirty percent less than the fescue norm used for
budget feeding.
The trial established that straight clover was a high
yielder of crude protein and a low yielder of fibre. A
ryegrass and clover mixture, from a feed quantity and quality
point of view, performed well.
Cocksfoot in general supplied the lowest yield of dry
matter per hectare and the fescue was found to be the highest
container of fibre and thus the lowest T D N supplier.
Kikuyu, although having a shorter growing season for the
area, gave the highest overall dry matter yield. The non-irrigated
kikuyu out yielded the irrigated kikuyu, a phenomenon
which needed investigation.
The addition of clover to the grass in the sward was
definitely advantageous.
Irrigation on average increased the air dry matter yield
by 2,81 ton per hectare. Due to irrigation, this extra dry
matter yield at 3 cents per kilogram dry matter meant an
extra gross amount of R76 per hectare.
Non-irrigated lowland pastures, with the exception of
straight clover, outyielded their counterparts under non-irrigated
topland conditions, the reason apparently being
that the lowland conditions have much cooler temperatures over
the year.
On the average, non-irrigated topland pastures yielded
0,12 ton of air dry matter per hectare more than the non-irrigated
lowland pastures. Clover pastures under non-irrigated
topland conditions out yielded the clover under non-irrigated
lowland conditions by 1 ton of air dry matter (A D M) /ha.
3. A comparison of the dry matter yields of topland irrigated
Ariki ryegrass, Danish cocksfoot and Kentucky fescue pastures
grown under farm conditions and under plot conditions showed
that plot yields on the average yielded 30 percent more than
the equivalent pastures on the farm (15,83 air dry matter/ha
versus 11,91 A DM/ha).
4. A comparison of Lolium multiflorum cultivars in the
Underberg area showed that over the six month winter period,
Tetila, Tetrane, Midmar, Local Hipkin and Local Hulleys were
significantly superior to the other cultivars under test.
Tetila, cultivar, a tetraploid type, gave the highest D M yield
of 9,77 ton per hectare. During the critical July and August
winter feeding period the cultivar Midmar out yielded all the
other cultivars by providing ,2,93 ton of dry matter per hectare.
Further, it was found that the diploid cultivars out yielded the
tetraploid cultivars during the mid winter period. It is
important to note that certain cultivars out yielded others, and
hence a specific cultivar should always be stated when applying
a norm for budget feeding exercises in the Underberg area.
A variation in the quantity and quality of the material on
annual ryegrass pastures over the May to mid September period
was very apparent. The average quadrat yield dropped from 2,71
kg wet material/m2 in mid May to 0,55 kg wet material/m2 at the end
of July. It is thought that heavy frosts dried the foggage out
and then heavy berg winds blew much of the conserved foggage away.
Over the test period the crude fibre of the ryegrass foggage varied
between 17,8% and 33,7%, while crude protein varied between 21,4%
and 11,9%. For budget feeding purposes no specific norm of yield
and quality of ryegrass foggage can be used over the winter period.
It appears to be impractical to apply an accurate ryegrass foggage
quantity and quality norm to an Underberg budget feed exercise.
An evaluation of a trial on the productivity of Underberg
veld with the aim of determining whether the budget feed norm of
0,5 M L U/ha/season carrying capacity was correct was undertaken.
All the results showed that 0,5 M L U/ha/season was not too high
and thus should the Underberg budget feed farmer be short of feed,
the fault would not lie in the fact that an incorrect veld carrying
capacity norm had been applied to his budget feed plan.
The assessment of the non-utilization of pastures by the
grazing animals on seven Underberg farms showed that on average
26,6% of the pasture was not utilized after one grazing. One
farmer utilized only 48,6% of the pasture available to him.
It appears that the non-utilization of pastures by the farmer
was one of the reasons why some Underberg farmers were short
of feed after attempting to carry out their budget feed plan.
8. Due to the high non-utilization figure of pasture by
grazing animals shown up in Chapter 4.1, a further similar
investigation on another twelve farms was undertaken. This
trial verified the Chapter 4.1 results by producing an average
non-utilization of pasture figure of 39,5%. One farmer in
this trial utilized only 40% of the available pasture at one
grazing. On nine of the twelve farms there was no apparent
advantage to be gained by such poor utilization since the
pastures were not subsequently regrazed.
By calculation from the protein and fibre figures the
highest T D N figure was obtained from the pure clover trial
in the pasture productivity study (Chapter 3). The clover
fed to an arbitrary 275 kg beef animal would provide the best
pasture for obtaining a 1 kg/day gain. Should bloat be a
problem the next best pasture, from the point of view of average
daily gain, would be kikuyu, which would supply enough nutrients
to allow a 275 kg animal to gain 0,85 kg/day.
The addition of clover to the grass sward improved the
quality of the pasture and appeared to have an economic effect
on both pasture and animal production.
It is apparent that the correct pasture type should be
grown by the Underberg budget feed farmer, as is shown by
the difference of 4,4 ton of D M in yield per hectare in
favour of kikuyu over cocksfoot when grown under non-irrigated
topland conditions.
10. It is important to use an accurate norm in a budget feed
plan. The current inaccuracy of as much as 39,1% in the budget
feed plan is unsatisfactory.
The validity of pasture productivity studies are discussed
in paragraph 5.7.1. Certain of the results were verified by
trials in an ensuing year.
The weaker links in the budget feed scheme formed the
main focus of this work. Certain variations in accepted norms
and principals in budget feeding are shown up, as summarized
below:-
pasture productivity studies, up to 39,1% variation from
norm used;
up to 24,2%;
up to 31,8%;
up to 26,7%; and
up to 39,2%.
plot versus farm pasture yield,
ryegrass cultivar trial,
non-utilization of pasture
trial,
non-utilization of pasture
trial II,
The above percentage figures averaged out at 32,3%.
A safety factor of 32% extra feed necessary for feeding
animals was built into eleven new Underberg budget feed schemes,
and the result was that no farmer who carried out his budget feed
plan complained of being short of feed.
Description
Keywords
Feed utilization efficiency, Range management, Pastures -- South Africa -- Underberg, Pastures -- Production, Dissertation (M.Sc. (Pasture Science))--University of the Free State, 1978