Moving Exam 3 Flashcards
One of your dairy cows is showing signs of lameness. If the forelimb is the source of lameness, which claw most likely has a lesion? And if it’s the hindlimb?
Dairy cattle bear more weight in the…
- MEDIAL claw of the FORElimb –> lesion is here
- LATERAL claw of the HINDlimb –> lesion is here
You are performing your distance exam for a lame cow, and you notice she has SYMMETRICAL, bilateral swelling just above her coronary band. What is your presumptive dx, and how would you treat it?
Foot Rot (until proven otherwise!) –> tx with systemic antimicrobials
You are performing your distance exam for a lame cow, and you notice she has ASYMMETRICAL swelling just above her coronary band. What is your presumptive dx?
Deep Infection (of the bone, joint, ST of the foot)
Where are MOST lesions located on a cow?
In the claw! Assess here first (unless obvious upper-leg lameness is noted)
You are examining two cows for lameness. Cow #1 has a flat back when standing, but arches it when walking with a slightly abnormal gait. Cow #2 is holding up her lame foot when standing, and arches her back when standing and walking. What are your locomotion scorings for each cow?
Cow #1 –> Score of 2/5, “MILDLY LAME” // most ideal to examine a cow at!
Cow #2 –> Score of 4/5, “LAME”
What is the importance of performing locomotion scoring in a herd?
It allows you to monitor the prevalence both within the individual herd and between herds of a geographical region. Helps estimate lost overall profits due to lameness, and whether or not current preventative measures are effective.
What time frame is a dairy cow MOST VULNERABLE to contracting foot problems, with regards to transitional movements?
The 3 weeks before calving and the 3 weeks AFTER calving!
How frequent should dairy cattle have their claws trimmed?
TWICE per year!
What are the 3 INFECTIOUS musculoskeletal dzs in cattle feet?
All = SKIN lesions:
1. Heel Warts (Digital Dermatitis)
2. Foot Rot (Interdigital Necrobacillosis)
3. Heel Erosion
What are the 5 NON-INFECTIOUS musculoskeletal dzs in cattle feet?
All = CLAW lesions:
1. Corkscrew Claw
2. Sole Ulcer
3. Thin Soles
4. White Line Disease
5. Sand Cracks and Hardship Groove (vertical and horizontal fissures)
Imagine you Dx a cow with FOOT ROT (interdigital necrobacillosis). Is this cow more likely to be beef or dairy? Describe how you came about your Dx, your Tx plan and suggested preventative measures. Also make sure to explicitly state any differences in Tx b/w infected beef vs. dairy cattle.
Foot Rot is most likely to affect a BEEF cow (out walking in muddy/moist pasture).
Dx: symmetrical // bilateral swelling just above coronary band. etiology = micro-trauma of interdigital epidermis
Tx:
- “F. necrophorum” = ANAEROBIC! –> open lesion / floss interdigital space to let O2 in. Do NOT wrap foot!
- ABX: Oxytetracycline (Beef!) and Cetiofur (Dairy! No milk withdrawal period).
Prevention:
- Practicality! Foot baths for dairy cows, minimizing muddy areas for beef cows. Improving abrasive walking surfaces.
You just dx a lame cow with the most common cause of lameness in U.S dairy cattle. What is the name of this disease, and what are its characteristics? How are you going to treat it, and what preventative measures do you recommend?
HEEL WART (DIGITAL DERMATITIS)
- Etiology = mechanical irritation & maceration of the [HIND] feet from surfaces like concrete –> DAIRY CATTLE! (live in closed confinements)
- M2 stage: painful, acute ulcer (strawberry-looking)
- Caused by anaerobic “Treponema” sp. (SPIROCHETE) –> Tx = Topical Tetracycline!
Prevention:
- Highly contagious & young cows are most susceptible –> do NOT introduce infected heifers into naive herd!
What is the chronic form of heel wart (DD) known as?
Hairy Wart – infected cattle are CARRIERS!
If a herd has high instances of heel erosion, then there is most likely a high prevalence of ____ _____ as well.
Heel Wart (Digital Dermatitis) –> both heel erosion and heel wart’s etiology = maceration from rough walking surfaces + poor hygiene
Describe the etiology of a sole ulcer.
Sole Ulcer = non-infectious cause of lameness
Risk Factors: Claw Horn Disruption, unkept hoof bi-annually hoof trims, 2º issue to heel erosion –> all lead to exposure/damage/infection of corium!
–> typically lateral rear claw
How do laminitis and white line disease differ with regards to abnormal rotation of the coffin bone?
Laminitis: coffin bone pulls away from the epidermal laminae of inner hoof wall (stratum internum)
WLD: coffin bone pulls away from hoof capsule entirely –> leads to separation of white line from the hoof wall
What can new barns do to prevent Thin Soles?
Smooth out abrasive walking surfaces
What is the typical treatment of Corkscrew Claw (CSC)?
CULLING b/c it is a HERITABLE misalignment of 2nd & 3rd phalanges of weight-bearing claw
Why don’t vertical wall fissures (sand cracks) typically cause lameness?
Because ~80% occur in the LATERAL claw of FORElimb = the NON WT-BEARING claw!
What are the common themes for tx of the non-infectious diseases?
- BLOCK on UNAFFECTED claw
- CORRECTIVE TRIMMING to re-establish normal balance
- Proper farm HYGIENE
- OPENING of lesion
- Proper NUTRITION
What is the most important preventative measure for Blackleg?
VACCINATION!
A CORE vaccine that’s administered 2x before calves are weaned (aka by 8 weeks post birth)!
What two nutritional deficiencies can cause Downer Cow syndrome?
Hypocalcemia (flaccid paralysis, hypothermia)
Hypomagnesemia (lush pasture in spring, which is high in water content)
What organism is most commonly responsible for causing ABSCESSES?
The ANAEROBIC, spirochete-shaped Truepurella spp. like “Actinomyces pyogenes”
OVINE:
How do the locations of lesions for Benign Foot Rot and Virulent (Contagious) Foot Rot differ?
Benign: INTERDIGITAL SPACE // TISSUE
Virulent (Contagious): IN THE FOOT (SOLE & WALL)
