If you want to bring 2 or more animals from various holdings temporarily to an assembly centre, for exhibition purposes at fairs, markets or exhibitions, regulations regarding animal welfare and the prevention of contagious diseases apply.
You must report animal exhibitions (in Dutch) in advance to the Netherlands Food and Consumer Product Safety Authority (Nederlandse Voedsel en Warenautoriteit, NVWA). For homing pigeons, flightless birds or poultry you have to report the event at least 8 days in advance. In order to prevent diseases from spreading, a veterinarian must inspect the birds at the location of delivery.
For cattle, sheep or goats, you must notify NVWA at least 30 days before the beginning of the event. For companion animals such as horses and donkeys this is at least 2 weeks.