When food is ingested, the larger particles pass through the digestive system faster. This faster rate of passage keeps the other food particles moving and prevents blockages such as hairballs. The digestive system works best when there is a consistent rate of passage instead of it continually changing due to varying types of feedstuffs. There is no way to guarantee how hay will look or feel from one year to the next. Factors such as maturity and weather produce different colors, textures, tastes and aromas with every harvest.
Some bunnies are particular about how hay smells, feels and tastes.
Encourage your rabbit to eat as much grass hay as you can get him to eat. All grass hay contains a low level of calcium, so feed your rabbit whatever type she will eat. Use a hay trough if your rabbit is confined to a cage for most of the day, or place several baskets or boxes full of hay around the house for the free-roamer. Rabbits should always have access to hay. Hay provides not only essential fiber and nutrition, but is mentally stimulating and helps rabbits keep their continuously growing teeth worn down.