<%@LANGUAGE="JavaScript1.3"%> Swine Production Management - Breeding  

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.

  1. Fill in each weeks results at the end of each week (day after the weaning day is day 1).
  2. When a breeding female falls out of the system record this is a different color (for example: red).
  3. Once you are below the target farrowing rate change color again (for example: blue.)
  4. 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)