Question

Which cutaneous gland of pigeon produces ‘pigeon milk’?
A. Uropygial
B. Preen
C. It is not produced by cutaneous but the crop gland
D. None of the above

Answer 1

Hint: Pigeon milk is a type of breeding milk. It is also known as crop milk. Pigeon milk is found in both the male and female birds. Moreover, cutaneous glands refer to the glands that are found in the cutaneous portion of our body or the skin.

Complete answer: Let us look at all the options that are given to us one by one.
Uropygial: Uropygial is also known as preen or the oil gland. It is a gland that is situated in the base of the tail of the birds. The uropygial is a bilobed sebaceous gland. The uropygial secretes oil to the dorsal surface of the skin.
-Preen: Preen is also known as the uropygial gland or the oil gland. It is a gland that is situated in the base of the tail of the birds. The preen is a bilobed sebaceous gland. The Preen secretes oil to the dorsal surface of the skin.
-It is not produced by cutaneous but the crop gland: The crop is a muscular pouch-like structure that is located in the neck of the birds. The crop is found internally therefore it is not cutaneous. Moreover, the crop is a structure and not a gland. It produces pigeon milk which is breeding milk. Thus, based on the above information we can conclude that the pigeon milk of pigeons is not produced by cutaneous but the crop gland.
Hence, the correct answer is option (C).

Note: Pigeon milk is breeding milk that is found in all the birds. The male releases the pigeon milk along with the sperms on the nest during copulation. The cloaca of the female sucks this milk inside the body to achieve internal fertilization. The name is pigeon milk so it is assumed that it is found only in pigeon birds only. However, this is not true. Pigeon milk is found very commonly in birds like pigeons and doves. In flamingos and penguins, pigeon milk is also referred to as crop milk.