The nursing sows will have an expected service date on the service list, which is 5 days after weaning off the litter they are nursing. That is, if they wean their own litter, for example on the 2nd of February and then wean the nursing litter on the 14th of February, they get an expected service date which is the 19th of February. If a sow is in service group 6 and then becomes a nursing sow, she will remain in service group 6 until the next service. She will not be on the service list for service group 6 when she is registered as a nursing sow . When she weans the litter, she will be on the service list in a new service group.