Gilt numbers
An idealized farm requires 100 pigs to be weaned per week,
therefore 10 to farrow and with an 85% farrowing rate 12 a week to
serve. This is a 250 sow unit or more precisely a farm which sells
6720 kg pig meat (96 finishers x 70 kg) per week
Use of the Csum:
The Csum is a visual aid to overall management and can help to bring
the whole farm together as it will predict output throughout the
various components of the farm.
- Fill in each weeks results at the end of each week (day after
the weaning day is day 1).
- When a breeding female falls out of the system record this is
a different color (for example: red).
- Once you are below the target farrowing rate change color
again (for
example: blue.)
- On a quick visual examination of the reporting sheet shown we
have too many 4 week returns, but few fall outs after week 5.
Using the Csum to predict gilt requirements:
In week 1, an ideal week, one sow returned, none of the
sows have any noticeable problems at 10 -14 weeks of gestation (i.e.
age, legs, teats), at least one gilt is required.
In week 2, two sows returned and at week 10 one sow was
noticed with chronic mastitis and would be destined to be culled, if
possible, at least two gilts required.
In week 3, while 12 sows are served, 12 sows are pregnant
at 28 days of gestation, one sow is selected for culling. At least
one gilt is required.
In week 4, only 10 breeding females are served, so even in
week one it is known that extra gilts will be required. Two
additional sows return and only 8 breeding females are found in-pig
at 28 days. In-order to ensure that sufficient breeding animals are
presented in the required service week at least 3 gilts are required
to be ordered.
In week 5, while 11 sows are recorded pregnant at 28 days,
two abort in week 10. While budget farming cannot provide sufficient
leeway for all eventualities, the effect of the abortions on the
farm's budget only need to last one production cycle. Additional
gilts are ordered to stabilize production. At least 2 gilts are
required.
Weeks 6 onwards indicate the progression of the Csum over
the next few weeks, clearly indicating the number of breeding
females served, the time of their loss and sows/gilts expected to
farrow.
If the close attention to details described here, is not
practical, as few sows drop out after week 10, it may be better to
maintain a larger gilt pool of at least 12-14 gilts to allow for
anoestrus and breeding company availability, to safeguard your
breeding target.
If the farm suffers from seasonal infertility/abortion problems,
plan these problems into the gilt management program. In
July/August/September order and serve extra gilts to compensate for
the inevitable 10% reduction in farrowing rate.
Gilts need to be regulated as well. For buying 10 gilts in one
batch, and they all synchronize and cycle in the same week is not
what is required. However, this is one of the commonest reasons for
excessive numbers of breeding females being presented to the
farrowing house. Purchase gilts in small enough groups, but watch
that transportation costs do not become prohibitive. Alternatively
purchase gilts of different weights, for instance at 85 kg, and 95
kg to encourage a two week spread. Some farms even purchase at three
weights, 75, 85 and 95 kg when purchasing every 6 weeks.
Model Csums
which can be used as a farm breeding board
Csum 1 week batch - 3 week
weaning
Csum 1 week batch 4 week weaning
(example)
Csum 2 week batching (3 week
weaning)
Csum 3 week batching (4 week
weaning)
Csum 4 week batch (3 week
weaning) |