In order to entry a gilt heat, you must access:

Management > Breeding herd> Data entry> females> Inventory, use the filter for gilts.

After that, fill the date of the heat and click on "save".

What is the time interval that i can entry heats?

Agriness S4 allows you to entry heats with an interval between 10 and 63 days. 

If you need to use another interval, you can change by accessing farm's settings. Access Farm> Settings> Management> Breeding herd> Validations > Rules for estrus.

But you need to adjust the settings between the limit of 10 and 63 days.

Where can i see this data?

There are two reports you can see this data:

1- Predicted Gilt Estrus - On this list you can see each and every estrus entered, it even if the gilt became a sow. 

Access: Management > Breeding herd> Analysis center> List > Predicted Gilt Estrus. Second and third estrus are only shown after the firs one is already entered.  

2 - Gilt Map - The gilt map will only show gilts that had its first estrus entered. 

Access: Management > Breeding Herd> Analysis Center> Performance> Gilt map