"
using intensive management
systems like synchronisation,
artificial insemination and by
applying intensive lambing
systems, farmers have
unfortunately still not managed
to constantly get weaning
percentages above 300%
in which dairy farmers farm with their cows –
mating again 73 days post lambing falls in the
middle of the “window of opportunity” in which
cows and ewes conceive best. Think of a dairy
cow – if you don’t get them pregnant by day 100
post calving, you will have difficulty in getting
them pregnant at all! Dairy cows can be kept on
zero-grazing systems or be managed on pastures
and are fed or supplemented in order to achieve
optimal production.
Intensifying sheep production means producing
more lambs, better lambs, more economically
and faster. In 4 words it comes down to – Quality,
Quantity, Efficiency and Efficacy. The last one
includes speed of production or faster. Think
of broiler production here – when I qualified in
1980, broilers were slaughtered at 7 weeks (49
days). This has come down to 31 days nowadays.
During the same time period sheep farmers
say that they have intensified, using intensive
management systems like synchronisation,
artificial insemination and by applying intensive
lambing systems, but have unfortunately still not
managed to constantly get weaning percentages
above 300% (let alone 400 and 500% which
are possible) and/or managed to decrease the
country’s inter-lambing period or the average
“days to slaughter”…
In and around 1988 I had my first client on the
STAR system.
In retrospect, we obviously “miss-understood”
many of the concepts which Magee and Hogue
implemented and after a few unsuccessful
attempts at early weaning, Mr Lourens van Eeden
from Swellendam started mating his ewes with
lambs at foot. In the same way beef producers
were doing with their cows. Despite lower
conception rates, as well as a lower fecundity
Volume 23 • Issue 02 • 2019
rate, he still managed to wean well above what
most other farmers were achieving. This made
me realize that there was something “different
and positive” in the “system”. I initially thought
that it was just the “value of time” - speeding up
production with shorter inter-lambing periods,
but now know that there was more to it than “just
that”.
In September 1991, I was asked to do a
presentation at the Rural Practioners Group-
congress (RPG / later on the “Livestock Health
and Production Group” and now RuVaSA)
at Mount Aux Sources in Natal, on Intensive
Sheep Production Systems. On revisiting the
proceedings, I found it interesting to note that
most of what I said then still holds true today!
A few those need to be highlighted again:
1. The Accumulative effect where 3 short
mating periods of for example 21 days each,
give better results than one long mating
season with the same amount of days, namely
63. Three opportunities to conceive in the
STAR system at 73, 146 and 219 days after
lambing bring us up to one year in total or the
equivalent of “once a year mating systems”..
So if a ewe only conceives by 219 days post
lambing, she achieves what het counterpart
does who was given one chance only.
If we have 1000 ewes of which:
•
•
•
•
•
60% conceive at 73 days (600 ewes), and
If the 400 ewes that did not conceive
(skips) does so at 60% after 146 days,
that gives us another 240 pregnant,
rendering 84% pregnancy, conceiving
“faster than the accepted normal”.
60% conception on the remaining
160 ewes gives another 96 and a
yearly conception of 93.6% after 3 low
conceptions of 60% each. This is what I
describe as the “Accumulative effect”
Three conceptions of 70% each leads to
a yearly conception rate of 97.3% in the
STAR system
We must therefore realize that when
analysing multiple systems in the “normal
way”, we can make serious “mistakes”.
This is much like the difference between
simple and compound interest!
2. The second “fact” is that the first
documentation of the STAR system was
by Brian Magee in 1983. Why, if we know/
knew that they achieved remarkable lambing
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