Macro-microscopic mammary gland structure in day-old dogs

The skin of the newborn female puppies (the 1 day age) has developed epidermis, but derma and hypodermic fatty tissue are at the stage of the development from the mesenhyma. On the ventral body's surface 8-10 nipples are evident in the mammary region. Each nipple has a good distinguishable milky flask and primary hair follicles developing from it.