
Integumentary System (Skin) • Skin: 3 Layers • 1. Epidermis • Thickness varies based on region • Stratified Squamous epithelium • Many flat layers of cells • Basal (Bottom Layer) produces new cells, oldest cells on top layer of skin. Dead skin cells are “shed” (dander) • Keratin= water proofing quality • Melanin (coloring), Albinism = absence of coloring
Integumentary System (Skin) • Skin: 3 Layers • 2. Dermis / Corium • Blood and lymph vessels • Nerve fibers (pain!) • Accessory organs • Connecting Tissue • Fibroblasts, collagen, histiocytes, mast cells, histamine, heparin, perception
Integumentary System (Skin) • Skin: 3 Layers • 3. Sub Q / hypodermis • Connective tissue • Fat • Adipocytes = fat cells that produce lipids
Skin: Appendages • Glands • Hair, wool, fur • Feathers • Scales • Claws, hooves, nails • Beaks • Horns/ Antlers • Horns: grow continuously • Antlers: Shed each season • Cornification: Skin-> horns/keratin
Vestigial Appendages • Vestigial: rudimentary structures, seldom used for survival, “left overs” from evolution • Dewclaws: rudimentary bones • Dogs: Digits 2 and 4 • Front and back legs. Back dew claw normally removes • Chestnuts: medial surface of (horse) legs • Ergots: tuft of hair on the fetlock joint
Common Procedures • Biopsy: removal of LIVING tissue for examination • Incisional • Excisional: removal of entire tumor • Culture: growing microbes in a predetermined media for study • Skin Scrape: microscopic examination of the skin for presence of mites • Intradermal Testing: injection of test substances under the skin to test for body reaction (allergies)
Common Procedures • Cauterization: destruction of tissue using electrical current/heat/ chemicals • Lance: open to allow for drainage
Common Ailments • Abrasion: superficial cut • Abscess: localized collection of pus • Alopecia: abnormal hair loss(bald spots) • Shedding: normal hair loss • Contusion: Bruise • Dermatitis: inflammation • Allergies, fleas • Mange: skin disease caused by mites • Ulcers (decubical): sores , bed sores
Lesions • Surface Lesions • Raised and discolored • Papule, macule, scale, wheal, plaque, patch, crust • Fluid-Filled lesions • Cyst, pustule, vesicle, bulla • Erosive • Ulcer, fissure
Activities • Review • Depict (YOU MUST DRAW IT) • skin layers and anatomy • Include a Hair follicle it must be colored and labeled (like the one on this ppt) • Types of Hair • Give examples of/ on animals • Example: What type of hair are whiskers? • Draw examples of the types of injections • Intramuscular, SubQ, Intravenous,Cyntesis • Know what/when they are used