Gross pathology of cattle- skin

Question 1

Breeds that get congenital lymphedema

Answer 1

Guernseys and Jerseys

Question 2

Gross signs of congenital lymphedema

Answer 2

Head swelling
Anasarca (diffuse swelling)
Dystocia

Question 3

What causes epitheliogenesis imperfecta? Gross lesion?

Answer 3

Defect in laminin V of hemidesmosomes
Sloughing of epidermis on extremities

Question 4

Ichthyosis congenita vs ichthyosis fetalis

Answer 4

Both hyperkeratosis due to reduced lipid transport- Congenita is dandruff, fetalis is plates of skin, fatal

Question 5

Calf with no hair, no teeth, no sweat glands

Answer 5

X-linked ectodermal dysplasia

Question 6

What virus causes hyperkeratosis and ulceration of the skin?

Answer 6

Bovine pestivirus (mucosal disease, BVD)

Question 7

Genetic cause of tearing of skin (called Ehlers-Danlos type VII in humans)

Answer 7

Dermatosparaxis

Question 8

Fist-sized fibrous papilloma (viral cause)

Answer 8

Papillomavirus type 1 or 2

Question 9

Papillomavirus that is usually peri-genital

Answer 9

BPV type 1

Question 10

Papillomavirus that is more generalized

Answer 10

BPV type 2

Question 11

Causes equine sarcoids

Answer 11

BPV type 1 and 2

Question 12

Causes papillomas in GI tract or urinary tract only

Answer 12

BPV type 4

Question 13

Which papillomaviruses don’t cause large fibropapillomas?

Answer 13

BPV 3, 4, 6

Question 14

Which papilloma virus affects teats and udders?

Answer 14

BPV type 6

Question 15

Cause of lumpy skin disease (young calf covered with skin nodules/pocks)

Answer 15

Capripoxvirus

Question 16

Cause of marked skin separation

Answer 16

Ergot alkaloid toxicity (fescue)

Question 17

What produces ergot alkaloids if they grow in fescue grass?

Answer 17

Claviceps purpurea
Neotyphodium coenophialum

Question 18

What causes foot rot?

Answer 18

Fusobacterium necrophorum

Question 19

Cause of serum and oozing from skin, causing hair to stick together (paintbrush lesion)

Answer 19

Dermatophilus congolensis

Question 20

Most common cause of ringworm in cattle; morph

Answer 20

Trichophyton verrucosum; multifocal hyperkeratotic dermatitis

Question 21

Cause of “cattle scab” (reportable)

Answer 21

Psoroptes bovis

Question 22

Cause of “leg mange”

Answer 22

Chorioptes bovis

Question 23

Cause of lumpy skin in older cow

Answer 23

Besnoitia besnoitiae

Question 24

Two species of cattle grub

Answer 24

Hypoderma bovis (overwinters in epidermal fat)
Hypoderma lineatum (overwinters in esophageal mucosa)

Question 25

Filarid parasite on underside of cow; gross lesion

Answer 25

Stephanofilaria stilesi; large plaques of hyperkeratotic, hyerpigmented, alopecic skin

Question 26

What is Copper important for in the skin?

Answer 26

Forming tyrosinase, pigmentation, and crosslinking of hair

Question 27

Photosensitization type I

Answer 27

Ingest preformed photodynamic toxins

Question 28

Photosensitization type II

Answer 28

Congenital deficiency in enzyme (least common)

Question 29

Photosensitization type III

Answer 29

Hepatogenous- can't convert chlorophyll due to liver damage (most common)

Question 30

Gross lesion with photosensitization

Answer 30

Skin ulceration in lightly pigmented areas