The optimum number of cattle per herd is thirty, with a minimum of 21 head per herd being required, even if there are less than seven teams entered.
- Roping steers shall not be used in Cattle Penning.
- All cattle within a herd must be numbered in groups of three.
- There must be three head of assigned cattle (with identical numbers or colors) per team in the herd as each new team begins a run.
- There must always be the same number of cattle in each of the herds used in a go-round.
- In the event more or less than three assigned cattle are discovered within a herd, the team(s) with more or less than the three assigned cattle must have a re-run at the end of the total go-round. Time for all other teams within such a misnumbered herd shall remain the same.
- Cattle cannot be re-used within a go-round of a division except as specified in a re-run as above.
- If no fresh cattle are available for re-runs, the cattle to be used will be determined by the show management and judge.
- If more than one run is given in any go-round, they will be taken in order of occurrence.
- If cattle are to be re-used and more fresh cattle are needed the used cattle must be mixed with the fresh cattle and re-numbered or color banded.
- Every attempt must be made to ensure each team works the same number of used and fresh cattle.
- In the event a team is given a number or colored neckband that has already been used within a given herd, a re-run must be given immediately, using the correct number or color within the same herd.
- Should the error be discovered after the herd has been removed from the arena, then the re-run will be given at the end of the total go-round using the same herd.