5 bovine musculoskeletal infectious diseases

Digital Dermatitis

• Early lactation cows & heifers

What is this? Who is at higher risk?

Digital dermatitis (aka strawberry foot or hairy heel warts)

This condition commonly affects dairy cattle (but it can happen in beef), problematic because it is costly for milk production

Spirochetes (Treponema most commonly)

What is the causative agent of digital dermatitis in cattle?

90% Rear feet, at plantar interdigital cleft

• shifts weight bearing to toe

• may also see it on dorsal aspect when it attacks corium = hairy attack

Where does digital dermatitis commonly occur?

hairy projections!

If digital dermatitis affects the corium what will it have?

Muddy/wet conditions

• Confinement housing

Genetic

Not washing hoof trimming equipment between cows

Purchasing replacement heifers from outside farms that are affected by condition (because it's contagious)

Name some risk factors for cows developing digital dermatitis

Individual:

• Clean with soap and water or under pressure

• Topical antibiotics (oxytetracycline), may be spray on

• Bandage

Herd:

• Clean with water

• Foot bath with *3-5% formaldehyde, copper sulfate*

How can you treat digital dermatitis?

Foot baths, biosecurity, improve environment hygiene

• NO vaccine (treponema vaccine is NOT effective)

How do you prevent digital dermatitis?

• Copper sulfate

• 3-5% Formaldehyde

  • No more than 5% = will cause chemical burn

What is used for foot baths?

Digital dermatitis

Mortellaro's disease, Raspberry heel, Footwarts, digital warts, Strawberry foot, and Hairy heel warts are all the same for WHAT?

Most animals respond well to treatment

Prognosis affected by:

• cleanliness at farm

• treatment at early stage

• amount of limbs affected

What is the prognosis like for cows affected by digital dermatitis? What is prognosis affected by?

FALSE. Treponema vx was tried but doesn't work

TRUE OR FALSE: The digital dermatitis vaccine is VERY effective

Interdigital dermatitis

This is superficial dermatitis of the interdigital skin, often painful to touch but not typically lame. More common in REAR FEET

Interdigital Hyperplasia AKA Interdigital fibroma (corn)

This is related to interdigital dermatitis, usually develops as a result of chronic irritation of the skin due to slurry, rock pasture, foot rot, poor conformation. More common in heavy animals

Chronic skin irritation = proliferative growth that may occupy part/all of interdigital space

• RARE lameness

Interdigital Hyperplasia occurs as a result of what? Does it cause lameness?

Foot anesthesia, pull claw apart, grab corn with towel clamp, excise corn, bandage with oxytetracycline

How can you remove "corns" or interdigital fibroma?

Foor rot

Interdigital necrobacillosis, Interdigital phlegmon, and Foul in the Foot are all the same name for WHAT?

Foot rot (interdigital necrobacillosis)

In cows, this is a mixed bacterial infection of soft tissues leading to ascending infection to tendons/ligaments. It enters through a defect in the interdigital skin

Fusobacterium necrophorum (same thing that causes white line disease and thrush in horses)

What is the PRIMARY causative agent of foot rot, which has different virulence factors like leukotoxins, endotoxins, and hemolysin

USUALLY ONE FOOT ONLY

• Swelling

  • Claws spread/coronary band

• Lameness

• FOUL odor

• Necrosis of interdigital space

What are some clinical signs for foot rot?

Wet conditions (rainfall or mud), trauma

• Macerated skin + injury/trauma = infection

Name some factors that predispose a cow to foot rot

Clean and debride interdigital space

Systemic antibiotics: ceftiofur, florfenicol, tulathromycin, oxytetracycline

Name the treatments for foot rot

• Minimize wet/muddy conditions

• Good hygiene

• 2 vx available but questionable

How do you prevent foot rot? is there a vx available?

Tenosynovitis: VERY edematous

• normally cull

This is inflammation of the tendon sheath, the protective covering surrounding a tendon, usually from ascending infection or penetrating wound. Causes severe lameness. You need to check for joint involvement

Pedal osteitis

This is inflammation and demineralization of P3, often secondary to other hoof problems. Cow will have chronic SEVERE lameness. You can diagnose with radiographs and treat with bone curettage, sequestrum removal, or claw amputation or cull

Osteomyelitis due to extension into coffin joint (do rads)

• Will have septic arthritis

• Amputate or ankylosis

What can foot rot lead to because of ascending infection? What is normally done to treat this?

1. Topical antimicrobials: foot bath, topical spray/bandage

2. Parenteral abx

3. Pain management: banamine & meloxicam

As an overview/in general, what are treatment options for infectious foot diseases?

Foot Rot (interdigital phlegmon, interdigital necrobacillosis)

What is this?

Heel erosion from interdigital dermatitis

What is this?

Digital dermatitis

What is this?

Digital dermatitis (with corium "hairy attack")

What is this?

Digital dermatitis

What is this?

Digital dermatitis (the bottom picture shows the most common location)

What is this?

Interdigital dermatitis

What is this?

Interdigital fibroma (corn)

What is this?

Interdigital fibroma (corn) AKA interdigital hyperplasia

What is this?

Interdigital phlegmon aka foot rot --> notice if you look at the dew claws in the top picture: the foot on the left has claws that are separated way further which shows you the severe amount of inflammation this animal is suffering from

What is this?

Neonates due to bacteremia/septicemia & umbilical issues

Who is septic arthritis more common in? Why?

Hock, stifle, carpus

• warm, swollen, painful joint

• more than one can be affected

Where is most commonly affected with septic arthritis and what will it look like?

Lavage

How do you treat septic arthritis?

Clostridium sordellii = ALWAYS FATAL

• getting stabbed by a sorde is FATAL

What is the MOST potent clostridial species?

1. Black Leg = C. chauvoei

2. Malignant Edema = C. septicum

3. Black Neck = C. sordellii

What are the 3 types of Clostridial Myonecrosis? What is their causative agent?

rancid butter

What does clostridial myonecrosis smell like?

• Abx: penicillin, tetracyclines

• Anti-inflammatories

• IV fluids

• Aggressive debridement

How do you treat clostridial myonecrosis?

VACCINE

• at least TWO doses

How do you prevent clostridial myonecrosis?

Early: prolapsed 3rd eyelid

Later: sawhorse stance

What is an early vs late sign of clostridium tetani?