2004). B-lymphocytes, the cells that produce antibodies, are initially produced in the embryonic liver, yolk sac and bone marrow, then move through the blood to the bursa of Fabricius (BF). Birds have a bursa of Fabricius (BF), which is an outpocketing of cloaca.
Most squirrels are vegetarians. There are a few exceptions like the flying squirrel. The flying squirrel will eat small birds, insects and definitely steal eggs from birds nest in order to make a meal. Generally speaking though, squirrels will mainly stick to things that are vegetarian related.
Flying squirrels are omnivores (eat both meat and vegetation). They like to eat different kind of food: slugs, snails, mice, eggs, small birds, mushroom, berries, seed, nuts, tree bark, flowersâ¦. Unlike other squirrels, flying squirrels form a single hole in the nut shell to reach the meat inside it. Other squirrels break the whole shell to release the hidden meat. Flying squirrels do not hibernate, but they slow down their activity during winter.