Histological investigations on the skin of the mammary gland of mares.

The research article is a study that explores the histological structure of different skin regions in mares’ mammary glands, with special attention to the dark pigmented udder skin.

Study Focus and Methodology

• The study was aimed at giving a histological overview of the varying skin regions in mares’ mammary glands, putting significant focus on the dark pigmented skin in the sulcus intermammarius region.
• The researchers carried out histological analysis, which is the study of microscopic anatomy of cells and tissues of organisms.

The Mammary Gland Regions

• Upon analysis, they were able to distinguish the dark pigmented udder skin into three parts: the Corpus mammae skin, the teat skin, and the sulcus intermammarius skin.
• The sulcus intermammarius lies between the two mammary glands. It is an area with a deep groove and presents a different skin structure compared to the rest of the udder skin.

Observations from the Study

• In the sulcus intermammarius, the whole epidermis was noticeably thicker than what is typical. This region specifically showed a significant thickening of the stratum corneum (up to 70 layers of cornified cells) and the stratum spinosum.
• These two layers are the outermost layers of the skin, with stratum corneum being the outermost layer composed of dead skin cells, and the stratum spinosum a layer underneath made up of keratinocytes, which are cells that produce keratin, a protein that provides strength and flexibility to the skin.
• The keratinocytes in the area were unusually large in size as per the study’s findings.

Conclusions Drawn

• The study dispelled the preceding assumption that the coating found in the sulcus intermammarius was a secretion from sebaceous glands. Through their findings, the researchers were able to establish that this coating was, in fact, a layer of stratum corneum.
• The research made clear that the papillae in the dermis, which are the ridges in the skin that actually produce the epidermis, terminated just below the stratum corneum. Having this kind of information helps us further understand the functional importance of this structure in horse physiology.