Lameness in sheep 1 + 2 Flashcards
(48 cards)
List some causes of lameness in sheep
- Footrot
- Contagious ovine digital dermatitis
- White line disease
- Foot abscess
- Interdigital hyperplasia
- Over grown claws
- Foreign body
- Arthritis
- Infections
- Fracture
- Muscular disease
- Neurological
Why is benign footrot a problem?
- Widespread in U.K 97% of flocks affected
- Flock level problem
What is the main pathogenic cause of benign footrot?
Dichelobacter nodosus
What are the clinical signs of benign footrot?
- Lame
- Interdigital skin inflamed, discharge, smell
- No horn under running
- Damage to skin may predispose to bacterial infection (damp conditions underfoot, frost and/or mechanical damage from long grass, thistles)
What is footrot?
Interdigital dermatitis plus….
Progressive under - running of sole of hoof horn starting at medial aspect of sole and progressing laterally
What is the primary aetiological agent causing footrot?
Dichelobacter nodosus
What is another possible aetiological agent of footrot?
Fusobacterium necrophorum
What are the main risk factors for footrot?
- Wet underfoot conditions
- Warm
- Muddy
- Where they gather
- Genetics
What is the treatment for benign footrot/interdigital dermatitis/scald alone no under-running of horn?
Topical treatment
Oxytetracycline spray
Foot bathing in antiseptic solutions e.g. formalin
Systemic antibiotics usually not necessary
Describe an appropriate foot bathing routine for benign footrot
- Antiseptic needs to be exposed to infected inter-digital area to be effective (approx 2 minutes depend on product)
- Feet clean beforehand
- Solution correct concentration
- Solution correct depth
- Dry standing afterwards (concrete)
- Repeat as necessary
What is the treatment for footrot (under-run horn)?
- Treat as quickly as possible
- Isolate lame sheep
- Treat individuals/groups of sheep
- Injectable long acting antibiotics best treatment
- Long acting oxytetracycline or amoxicillin
May require repeat treatments
Is trimming recommended for lame sheep? why?
Trimming and topical treatment is not recommended as a method to treat or control footrot
- Trimming diseased feet delay healing
- Trimming may spread disease hands and clippers
- Studies have shown that if you treat the infection with antibiotics the foot shape will return to normal alone
Describe the clinical appearance of contagious ovine digital dermatitis
- ulcerative/proliferative lesions start at the coronary band
- Progressive under running of the hoof wall
- Hoof sloughs off
- Often mixed infection in flocks with footrot
Describe grades 1 to 5 of contagious ovine digital dermatitis
Grade 1 = coronary band lesion only
Grade 2 = Less than 50% of horn capsule separated
Grade 3 = 50-100% of the hoof capsule off
Grade 4 = Healing but active lesion still present
Grade 5 = Healed
What are the risk factors for contagious ovine digital dermatitis?
- Seasonal in later summer/early autumn
- Large flock size
- Lowland/lush pasture
- Prevalence of footrot
How is contagious ovine digital dermatitis treated?
- Isolate affected
- LA amoxicillin (usually require repeat injections)
- Treat until clinical cure
- Macrolides licensed for sheep useful as long acting
How is contagious ovine digital dermatitis treated?
- Isolate affected
- LA amoxicillin (usually require repeat injections)
- Treat until clinical cure
- Macrolides licensed for sheep useful as long acting
What are some key features of managing infectious foot disease?
As soon as individual animal is seen lame it should be treated
- Welfare
- Disease spread
- Law!!
Contagious flock level problem often necessary to treat whole flock
Footrot massive risk factor for CODD so vital to control both together
What are the aims of the 5 point plan?
- Reduce disease challenge
- Build resistance
- Establish immunity
What are the 5 points of the 5 point plan for infectious lameness disease control?
- Vaccinate twice yearly with footvax
- Treat lame sheep quickly
- Biosecurity
- Environmentally challenge
- Cull chronically lame sheep
Describe the benefits of the footrot vaccine
- Treats and Prevents footrot
- Cure rates 70-100% reported
- Very useful product on many farms, where struggling to keep on top of lameness particularly low staff numbers, large units and where prompt individual treatment isn’t feasible
What are the 4 contraindications for FootVax
- Oily adjuvant can cause injection site lumps
- Not used prior to shearing
- Not use close to lambing
- Not use if sheep had moxidectin 1%
Describe the dosing schedule for FootVax
- Initial vaccination 2 doses 4-6 weeks apart
- 6 monthly booster at risk periods
What are some biosecurity considerations for managing infectious lameness disease
Bought in sheep
- Don’t buy in new diseases or new strains of disease.
- Isolate
Be aware of anthelmintic resistance
Treat scab
Check for footrot lesions
Treat all sheep with Footvax
