Lameness Van Stratten

Diseases of the bovine digit

Michael van Straten

Diseases of the bovine digit: program

IntroductionInfectious diseases of the bovine digitLaminitis and secondary diseasesFoot baths

Welcome

Bovine Claw

InfectionImmune system

Hygiene

ManagementHumidity

Density

ManurePlanning

SurfaceSlipperiness

Trauma

BehaviourTime lying down

Cow comfortSocial confrontationPhysical activity

Stress

Nutrition

Rumen environment

BalanceHigh energy

Fiber quality

Grazing managementBuffers

Excessive fertilization

Genetics

Claw volume

Conformation Vitamins & Minerals

BalanceRequirements

Natural supplyFactors affecting

availability

Lameness: A clinical sign or

symptom of a disorder that causes a disturbance in locomotion.

May be caused by a metabolic or systemic disturbance, injury to the musculoskeletal system, or infection.

Economical Importance 1

• Production losses: Feed intake Body weight Milk production sexual activity

• Economical losses:-Decreased (re)production.-Increased culling rate (carcass condemnation).-Veterinary costs.-Increased labor for management & treatment.-Lame cows more susceptible to other diseases.

Economical Importance 2

• Treatment: Vet costs 150 NIS + 2 NIS beyond 10 km + drugs + time. A cow that has become lame:1.6 greater chance of being lame in same lactation.

• Discarded milk: due to drug treatment. App. 1.40 NIS/ liter, 6 days of 20 l (milk drop)= 168 NIS.

• Yield reduction: if 60 l= 84 NIS.• Weight loss: 100-200 kg = 450-900 (lowest).• Reproductive problems: if open days increased by

21: (extra open day @ $5) = 367.5 NIS.

Economical Importance 3

• Opportunistic cost: Other tasks are neglected• Culling: Involuntary culling ranks after infertility,

udder problems and low production.U.S. 1.2% of culls (Milian-Suazo et al., 1988)Switzerland 7.7% (Frey & Berchtold, 1983)Germany 14% (During, 1988).

Losses due to difference cull price and replace-ment price, loss of future lactations, and loss of carcass weight.

• Susceptibility to other diseases: e.g. mastitis

Infectious diseases of the digit

• Phlegmona interdigitalis

• Dermatitis interdigitalis

• Dermatitis digitalis

Phlegmona Interdigitalis

• Interdigital phlegmon, foot rot, foul in the foot, panaritium.

• A subacute or acute necrotic infection originating from a lesion in the interdigital skin.

Phlegmona InterdigitalisEtiology & Pathogenesis

• Local injury of claw skin is a prerequisite for an infection.

• Maceration of skin by water, feces or urine may predispose claw to injury.

• Fusobacterium necrophorum in synergism with Porphyromonas levii are the predominant isolates in interdigital phlegmon.

Phlegmona InterdigitalisFusobacterium necrophorum

• Obligate, anaerobic gram-negative bacterium.

• Biotypes A & AB produce a potent endotoxin, as well as an exotoxin with leukocidal and hemolytic properties.

• Toxins induce necrotic cellulitis.

• Synergism in mixed infections.

Phlegmona InterdigitalisClinical signs 1

• Usually one digit affected, more common in hind legs.

• Can occasionally occur in several claws in calves.

• Onset is rapid, extreme pain causes lameness.• Animal tries to avoid contact with ground.• Body temperature is raised, appetite and milk

production significantly reduced.

Phlegmona InterdigitalisClinical signs 2

• Swelling and erythema of the soft tissues of the i.d. space and coronary band.

• Inflammation may extend to pastern & fetlock.

• Claws separated with edema between digits.

• Fissures appear in the i.d. skin, tissues become necrotic and a foul odor is present.

Phlegmona InterdigitalisComplications

• Severe weight loss and reduction in milk yield.• Infection of distal interphalangeal (DIP) joint

is possible.• Involvement of navicular bursa, flexor tendon

sheath, distal ligaments & phalangeal bones may produce a retroarticular abscess.

• Osteomyelitis or infectious arthritis.• Severe digital cellulitis can lead to septicemia

or toxemia.

Phlegmona InterdigitalisDiagnosis

• Sudden lameness (most often in one limb).• Elevated body temperature.• Swelling of the digital region with or

without claw separation.• Typical lesion of the interdigital skin.• Ddx: Retroarticular abscess, Septic arthritis of

DIP joint, Advanced cases of DD or DI, Foreign body.

Phlegmona InterdigitalisTreatment

• Systemic antibiotics (procain penicillin, oxytetracycline, TMPS and others).

• High doses often needed.

• Most animals recover in a few days.Prevention (?):

• Hygiene and proper drainage in stalls.

• Footbaths (formaldehyde).

Dermatitis Interdigitalis

• Interdigital dermatitis, foot rot, slurry heel, stinky foot, scald.

• An inflammation of the interdigital epidermis caused by a bacterial infection.

• Dichelobacter (Bacteroides) nodosus is the most frequently isolated infectious agent.

Dermatitis InterdigitalisIncidence

• Worldwide, most prevalent under poor hygienic conditions in intensive dairy farms.

• Morbidity may be 100% in infected herds.

• In tied systems hind limbs more often affected, in loose house systems distribution about equal.

• Floor type and nutrition influence prevalence (Frankena et al., 1993).

Dermatitis InterdigitalisEtiology and pathogenesis 1

• Caused by a mixed bacterial infection.• D. nodosus alleged to be predominant

agent.• Experimentally, D. nodosus can be

transmitted from cow to cow and cow to sheep.

• Synergism with other agents, F. necrophorum in particular.

Dermatitis InterdigitalisEtiology and pathogenesis 2

• Disease is strongly associated with high relative humidity, temperate climates and poor hygienic conditions.

• Source of infection is cow itself, infection spreads through environment.

• D. nodosus cannot survive for more than 4 days on the ground.

• Differences in pathogenicity of bacteria.

Dermatitis InterdigitalisEtiology and pathogenesis 3

• Manure mixed with fine chopped bedding material adheres to claws and produces environment that favors growth of bacteria.

• Bacteria cause loss of integrity of epidermal cells but do not pass basement membrane.

• As infection proceeds, border between skin and soft heel horn is destroyed.

Dermatitis InterdigitalisClinical signs 1

• Mild cases or initial stages:

-Hyperemia of interdigital skin including dorsal or palmar/plantar areas.

-Superficial erosion or ulceration with serous or grayish exudate.

Dermatitis InterdigitalisClinical signs 2

• Aggressive forms:-Interference with horn formation in bulbs: fissures, hemorrhages and necrosis. -Subcutaneous tissue can be secondarily inflamed.-Swelling & hyperkeratosis interdigital hyperplasia.-Most common complication: heel horn erosion.

Dermatitis InterdigitalisDiagnosis

• Characteristic superficial lesions of interdigital epidermis.

• Isolation of D. nodosus: microscope & IFT.

• Ddx: -Dermatitis digitalis.-Some systemic viral diseases:

FMD, MD, MCF

Dermatitis InterdigitalisTreatment

• ID should be treated topically.• Lesion should be cleaned, necrotic tissue

removed and a topical bacteriostatic agent applied (e.g. 50% mixture of a sulfanomide powder and copper sulfate.

• Foot bathing (also for control)• Lesions usually regress spontaneously if

environment improved.

Dermatitis InterdigitalisControl

• Good management & housing systems!

• Regular foot trimming.

• Foot baths.

• Vaccination has been of little benefit in cattle.

• Oral administration of zinc preparations?

Dermatitis Digitalis

• Digital dermatitis, Mortellaro, Foot wart, Papillomatous digital dermatitis, strawberry foot rot.

• A contagious, superficial inflammation of the epidermis proximal to the coronal margin or the interdigital space.

Dermatitis Digitalis

• Two types:

A circumscribed, erosive/reactive condition.

A proliferative, wartlike condition.

Dermatitis DigitalisIncidence

• Animals of all ages and breeds susceptible.• Most common in heifers on entering

milking herd. (immunology?)• Disease can spread rapidly in herd.• Morbidity can reach 90%.• Pelvic limbs more often affected.• Can be transmitted by apparently healthy

animals.

Dermatitis DigitalisEtiology

• Both forms possibly seen on different animals on same farm: different stages?

• Most probable: multifactorial disease.

• Spirochaetes (2 types) isolated.

• Other bacteria also involved (“mattress” forming)

Dermatitis DigitalisClinical signs 1

• Circular lesion, 1-4 cm in diameter, generally seen in plantar (palmar) skin adjacent to heel or in proximal part of interdigital space.

Dermatitis DigitalisClinical signs 2

• Erosive form: Skin covered with purulent, pungent smelling exudate. Cleaning exposes reddish granulation tissue (strawberry) with concave profile.-Whitened epithelial border.-Lesion sensitive, bleeds easily, soft tissue not swollen, animal lame.

Dermatitis DigitalisClinical signs 3

• Proliferative type: Papillomatous type: mass of hard, up to several centimeters long, fine tendrils. Bleed easily if traumatized.

• Complications: uncommon. If adjacent to growing horn: heel horn erosion possible. Sole ulcer & vertical fissures very rare.

Dermatitis DigitalisDiagnosis

• Epidemic onset of discomfort and lameness in herd.

• Inspection: lift & restrain limb.

• Wash affected area: circular lesion, often strawberry surface, painful. Often pungent odor.

• Ddx: Dermatitis interdigitalis.

Dermatitis DigitalisTreatment 1

• Local treatment:-Trimming, remove necrotic tissue.-Clean & dry lesion.-Spray with aerosol containing oxytetracycline hydrochloride.-Bandaging not necessary!-Repeat treatment if necessary.

Dermatitis DigitalisTreatment 2

• Herd outbreaks: Footbaths.Oxytetracycline 5-6 g/liter.Lincospectin 0.75-1.5 g/liter.

Possibly repeat after 4-6 weeks. Environment!!!

• Cu-sulfate, Zn-sulfate, Formaline> poor results.

• Chronic lesions: resection of proliferation.

Dermatitis DigitalisControl

• Hygienic conditions.

• Routine inspection of feet.

• Disinfection and quarantine procedures before new animals are introduced into herd.

• Vaccination has not been successful.

Reaction to footbath

TherapyLocationDisease

Prevention±Systemic (injection)

Phlegmona interdigitalis

Prevention & Therapy

LocalInterdigital dermatitis

Non (?)LocalDigital dermatitis

Infectious diseases of the digit

Laminitis

• A disease condition of the claw due to a disturbance in the microcirculation of the corium.

• Degenerative and inflammatory changes at the dermal-epidermal junction.

LaminitisEtiology & Predisposing Factors 1

• Carbohydrate overload already known by ancient Greeks.

• Systemic insult.

• Ruminal acidosis (Lactic acidosis).

• Endotoxemia.

• Histamine.

• Fiber quality.

LaminitisEtiology & Predisposing factors 2

• Excess protein (?).

• Average daily weight gain.

• Genetic predisposition.

• Breed susceptibility.

• Exercise.

• Mechanical factors.

• Deficient keratinization.

LaminitisPathology and Pathogenesis

• Phase 1: Changes in dermis & dermal-epidermal junction during clinical laminitis:

Mechanical factors & systemic factors cause opening of the arteriovenous shunts in the dermis of the wall beneath the coronary band and inflammation of the laminae of the dermis.

LaminitisPathology & Pathogenesis

• Following opening of the arteriovenous shunts:

• Hemostasis: Stasis of blood within claw and hypoxic damage to vessel wall.

• Hemorrhage: Large hemorrhages occur around the apex of the distal phalanx. Edema in corium.

• Thrombosis: In large and small vessels, due to increase in intraungular tissue pressure.

• Necrosis.

LaminitisPathology & Pathogenesis

• Phase 2: Compression of the dermis in the sole & heel.

Further capillary damage. Further pain. Severe lameness.Areas of necrosis usually focal.Still no abnormality visual to clinician.

LaminitisPathology & Pathogenesis

• Phase 3: Development of lesions in the capsule.

• Changes in coronary band: band becomes irregular, rough, grooved or thickened.

LaminitisPathology & Pathogenesis

• Changes in the Wall:Horizontal Grooves: due to disturbed horn production.Concave dorsal wall: direction of horn growth alters at horizontal grooves, causing dorsal surface of claw to become concave.Fissures: If insult has been severe, continuity of wall is lost. Formation of loose fragment.

LaminitisPathology & Pathogenesis

• Changes in the Lamellar Region:Widening (separation) of the white line (W.L.).Port of entry for foreign matter & infection.A double or hollow wall may result.

• Changes in the sole:Hemorrhages in the horn.Double soles.Ulcers in the sole and toe.W.L. separation and/or deformation of the claw.

LaminitisInterdigital dermatitis

White line disease

Double sole

Sole ulcerHeel erosion

Nutrition, environmental factors, management etc.

Secondary claw diseases

Sole ulcer

A specific lesion located in the region of the sole-bulb junction. Damage to the dermis is associated with a circumscribed zone localized hemorrhage and necrosis.

Sole UlcerIncidence

• Often one or both lateral hind claws or medial fore claws.

• Common in dairy herds worldwide (Europe)• Incidence increased when cows are fed high

levels of concentrate or protein.• More common in Friesians (?).• More common on concrete floors.

Sole UlcerEtiology & Pathogenesis

• Current opinion: subclinical laminitis damages horn producing tissues sole horn is softened.

• Lesion occurs adjacent to plantar process of distal phalanxmechanical & anatomical factors.

• Outer hind claw broader, its distal phalanx is rougher.

Sole UlcerPathology & Pathogenesis

Corium

Plantar process of P3

Sole

MechanicalPressure

Ischemic necrosis

Poor quality hornHemorrhageUlceration

Sole UlcerClinical signs 1

• Most cases in lateral claw of one or both hind limbs.

• Progress & severity of lameness variable.

• Limb often held slightly abducted.

• Animal tries to relieve pressure from heel area. May shake foot, shift weight from foot to foot and lie down more often.

Sole UlcerClinical signs 2

• Lesion varies from soft discolored area to obvious circumscribed perforation.

• In later stages, granulation tissue protrudes through sole defect. Prolapse of corium also possible.

• Lesion is painful.

•Infection can invade into deeper structures.

Sole UlcerTreatment

• Therapeutic claw trimming (surgery).

• Lower affected claw and/or use claw block.

• No need to control granulation tissue and better not to bandage.

• Examine contralateral digits.

• If lesion is purulent, parenteral antibiotic therapy is advisable.

White Line Disease

• Disintegration of the fibrous junction between the sole and wall and its penetration by debris.

• Abaxial white line, distal to heel bulb junction of lateral hind claw is commonly affected.

White Line Disease

• Dirt & grit embedded in the soft horn can cause lameness (pressure on corium).

• In case of abscess, pressure & inflammation cause lameness.

• Intraungular pressure causes pus to spread from the initial focus to underrun the wall or sole.

White Line Disease (heel)

Purulent abscess

Coronary band(sinus formation)

Skin-horn junctionheel

Navicular bursa(septic arthritis)

White Line DiseaseEtiological factors

• Abaxial border of sole absorbs maximum pressure when standing.

• “Shock absorber” working of wall.

• Laminitis.

• Hard surfaces, wet conditions, claw deformities.

• Bedding materials (track), herding.

White Line DiseaseClinical signs

• Usually lateral claw of hind limbs.

• Limb usually abducted.

• In severe cases, claw is hot & painful.

• Coronary sinus formation or separation of heel horn may be seen.

• Severe lameness & heel swelling if navicular bursa or DIP joint involved.

White Line DiseaseTreatment

• Drainage: remove foreign bodies & debris. Create an opening.

• “Rest”: reduce heel height and thin sole around lesion. Remove elliptical segment of wall adjacent to lesion.

• Abscessation with sinus formation to coronary band: removal of abaxial wall throughout length of defect (surgery).

Heel Horn Erosion

• Irregular loss of bulbar horn.

• Exposure to an unhygienic moist environment.

• Considered to be a complication of dermatitis interdigitalis.

• Usually, typical V-shaped grooves present.

• Treatment: therapeutic trimming.

Interdigital Hyperplasia

• A proliferative reaction of the i.d. skin or subcutaneous tissue forming a hard mass.

• Corns, tyloma, limax, fibroma, wart.• Caused by chronic irritation or dermatitis in

interdigital region.• Degree of lameness depends on size and

situation of lesion.• Surgery may be necessary.

Footbaths

• Not a substitute for hygiene!

• Control: Dermatitis interdigitalis. Phlegmona interdigitalis

(?).

• Treatment: Herd medication for dermatitis digitalis.

• Walk-Through vs. Stand-In footbath.

Minimal Footbath Dimensions

250 cm

100 cm

15 cm

Fluid level 10 cm

Formalin

• Concentration 3-5% . Irritant chemical!

• Very good antibacterial activity.

• Not irritant in concentrations < 5%.

• Cheap.

• Hardens claw horn.

• Retains effectiveness relatively well in presence of organic material.

Formalin

• Do not use on open lesions.• Never use before entering milking parlor. Site bath

in well ventilated area.• Use bath twice daily for 3 days, repeat every 3-4

weeks. After footbath, allow cows to stand or walk on clean floor for 5-30 minutes.

• Replace fluid when contaminated, renew after every 400-500 uses.

Copper Sulfate and Zinc Sulfate

• Expensive, slightly less effective.

• Rapidly loose potency in presence of manure.

• Copper sulfate is irritant.

• When used in in a 250 liter bath, it is recommended to change fluid after 100 cow passages.

Antibiotics in Footbaths

• In use by some veterinarians for treatment of digital dermatitis.

• Expensive.• Can be hazardous to environment and

increase resistance of organisms to antibiotics.

• Use for 2 consecutive days and repeat after 3-5 days.