Hoof/Claw Flashcards
Hoof capsule
epidermal part of the hoof
Parts of the Hoof
epidermis and dermis
Foot
hoof capsule + everything inside it (CCT, bn, etc.)
Corium
dermis
keratinized surfaces of hoof
wall, sole, frog
hardness of keratin (Hardest to softest)
wall > sole > frog
Divisions of hoof wall
Stratum externum
Stratum medium
Stratum internum
Stratum Externum
- outermost layer of hoof wall
- very thin! thickest proximally
- made of horn tubules & intertubular horn
Stratum Medium
- middle layer of hoof wall
- VERY thick.
- made of horn tubules and intertubular horn
- very dense & tough.
- were shoe nails go
Stratum Internum
- innermost layer of hoof wall
- lots of projections/laminae that run from proximal to distal (PRIMARY LAMINAE)
- ridge inside hoof wall, seen grossly, non-pigmented
Hoof capsule made by…
stratum basale!
5 epidermal regions of the hoof
- Stratum Externum
- Stratum Medium
- Stratum Internum
- Sole
- Frog
What supports the epidermal regions of the hoof?
dermis or corium
5 dermal regions of hoof
- Perioplic Dermis
- Coronary Dermis
- Laminar Dermis
- Sole Dermis
- Frog Dermis
Perioplic Dermis supports
stratum externum
Coronary dermis supports
stratum medium
laminar dermis supports
stratum internum
sole dermis supports
sole
frog dermis supports
frog
Perioplic dermis
- narrow layer of dermis
- supports stratum basale
- small dermal papillae present
Dermal papille
run from dermal region into the epidermal region to supply it with nutrients
Coronet
junction of skin of distal leg with proximal boundary of the hoof wall.
A LINE
Coronary band
a region.
common name for the coronet
Perioplic region
soft region of epidermis in the proximal hoof wall
proximal part of stratum externum
Another name for the Perioplic Region
periople
Hardness of hoof
wall > sole > frog > periople
Coronary Region
junction between coronary dermis and epidermis
Laminar region
junction of laminar dermis and laminar epidermis
NO papillae with laminar dermis
Sole Region
junction between sole dermis & sole epidermis
Frog region
junction between frog dermis and frog epidermis
White Zone
- white line
- junction between sole and wall (on bottom of hoof)
Stratum externum made by
stratum basale in periople
Coronary Dermis
- supports stratum basale
- large dermal papillae present
Stratum Internum interaction with Laminar Dermis
primary dermal laminae interdigitate with primary epidermal laminae
AND
secondary dermal laminae interdigitate with secondary epidermal laminae
LOOKS LIKE FEATHERS!
Secondary dermal and secondary epidermal laminae
extensions of primary laminae
Secondary epidermal laminae
lined by stratum basale that produces epidermis of stratum internum
Horn Tubule (Tubular Horn)
epithelium overlying the dermal papilla
Intertubular horn
epithelium between dermal papilla
Growth of epidermal hoof (hoof capsule)
stratum externum -> proximal to distal
stratum medium -> proximal to distal
stratum internum -> inside to outside
Do secondary epidermal laminae move in growth?
NO. their stratum basale cells must remain attached to basement membrane.
Cloven Hoof
- walk on 2 pointed toes
- no frog or bars
- bulb of heel is present
- sole, wall, white zone/line present
Non-equine hoof vs. equine hoof
Non-equine hoof has ONLY primary epidermal and dermal laminae!
NO feathers!
Claw
cornified (keratinized) structure
Claw plate
2 lateral sides/walls
central dorsal ridge
dorsal midline of the claw
sole of claw
flaky keratin underneath claw walls
Sections of a claw
Dermis, stratum basale, stratum spinosum, stratum corneum,
Coronary border of claw
proximal border of claw
Where is stratum basale of claw most active?
coronary border and dorsal ridge of claw
Where is most of the claw made from?
Stratum basale at coronary border and dorsal ridge
Where is stratum spinosum thickest at?
dorsal ridge area
Sole contains…
stratum granulosum and stratum lucidum
Dermis in claw
- underlies & supports stratum basale & spinosum
- fills area between distal phalanx & epidermal structures
- fuses with periosteum of distal phalanx
Claw growth
- proximal to distal in circular fashion.
- originates from coronary border under claw fold
Horn Tubule Function
To absorb & distribute the concussive force of the hoof wall as it hits the ground. the horn tubules act as “springs” or “spring steel” in the hoof wall
