Pears are a fruit that is high in sugar. Feeding pears to rabbits can lead to diarrhea if you feed them too much. Rabbits are better suited to eating hay that provides a high fiber diet needed to feed the good bacteria in their digestive system. A digestive tract full of healthy bacteria can produce many of the B-vitamins and other nutrients that your rabbit needs to stay healthy. Feeding them sweet foods actually upsets the balance of bacteria in their gut and will favor the growth of bad bacteria that cause diarrhea and bloating.
Adult rabbits will be healthiest eating a grain-free and soy-free pet rabbit food that is enriched in chelated minerals and balanced with natural vitamins. When balanced properly these nutrients will greatly increase their health and your bunny will be more playful and you'll see a big improvement in the quality of the fur coat. If they are already obese then this style of a diet will help them loose the unwanted weight. If they are underweight due to old age or lack of health then this style of feed will help them gain "much needed healthy weight."
Baby rabbits grow quickly and need a high fat diet like "mamma's milk" and balanced protein to support healthy growth. It is very important to make sure they get a high fiber diet that is low in starch (grain and grain by-products). Otherwise it will upset the balance of good and bad bacteria and lead to the same problems mentioned above. Most rabbit food is loaded with grain and soy, two things that should be avoided to maintain a healthy rabbit.
So, can rabbits eat pears? It is not recommended but most rabbits will love pears and you should limit feeding them only a very small amount as a treat.