In short, yes you can use a fridge or a freezer trailer to transport your stock. However the trailer will not be able to be powered and running whilst in transport. This means it will only be useful for shorter journeys. Stock can be chilled or frozen ready for the journey and will not be affected too much by the short length of time it is not plugged in.
You will also need to make sure that your stock is secure inside of the trailer. You want to make sure that it does not move around and get damaged during the journey.
Another consideration you will have is the weight within the trailer and the positioning of that weight. Ideally it would be best to have most of the weight over the axles and the maximum payload of the trailer is 1250kg.
For longer journeys or for heavier loads our trailers are likely not to be the best solution. We would recommend using a cold storage courier or hiring a fridge or freezer van. Both of these options will be able to refrigerate and keep the stock cold whilst in transport.