Art. 551. Kinds of fruits. Fruits are things that are produced by or derived from another thing without diminution of its substance. There are two kinds of fruits; natural fruits and civil fruits. Natural fruits are products of the earth or of animals. Civil fruits are revenues derived from a thing by operation of law or by reason of a juridical act, such as rentals, interest, and certain corporate distributions. Acts 1976, No. 103, §1.