Rabbits can eat prickly lettuce, but it's important to note that it should be fed to them in moderation. Prickly lettuce, also known as Lactuca serriola, is a wild lettuce plant that is commonly found in many regions around the world. While it is safe for rabbits to eat, it contains a high level of lactucarium, a white, milky fluid that can cause diarrhea if consumed in large quantities. Therefore, it's important to introduce prickly lettuce slowly into your rabbit's diet and monitor their intake. You should also ensure that the lettuce is clean and free from any pesticides or other harmful chemicals. As with any new food, it's best to consult with your veterinarian before introducing it to your rabbit's diet. Remember that a rabbit's diet should consist mainly of hay, fresh vegetables, and a limited amount of pellets. Variety is key, so it's a good idea to offer your rabbit a wide range of safe vegetables in small amounts to keep their diet interesting and balanced.