After selection the animals are mated for the first time and offspring will be born. In this example animals on average will have two batches of offspring (single or litters). The length of the generation interval is equal to the age in between the births of both batches. Assumption in this figure is that the number of offspring born in each batch is the same. If not, then the (length of the) generation interval needs to be weighted weighed according to the number of offspring in each batch.
...
If we briefly go back to the example with the jumping rabbits: The breeder was happy when selection was based on performance of 12 offspring. However, he may want to look into the matter in more detail because it will depend on the litter size whether this number can be achieved with a single batch of offspring, or whether multiple batches are required. Multiple batches mean more time and the generation interval in rabbits is low. In such situations it may be a consideration to accept a slightly lower accuracy of selection, but manage more generations of selection in the same time frame. It may result in more genetic gain per time unit in the longer run.
Thus:
| Paneel | ||
|---|---|---|
|
...
Thus: optimizing genetic gain will require a balance between increase of the accuracy and increase of the generation interval |