Lecture 27 4/7/25 Flashcards
What is the anatomy of the small ruminant foot?
-sole thickness of 2 to 3 mm
-horn growth rate of 5 mm/month
-pointed triangle shaped digits
-all weight bearing through P3
What are the general characteristics of hoof trimming in small ruminants?
-do not need any fancy equipment like a tilt table
-easy to restrain with halter and tie; can pick up feet like a horse
-should do trims 2 to 3 times a year
-frequency of trims depends on growth, nutrition, and development
What should be assessed during a hoof inspection?
-horn
-skin
-interdigital space
-swelling and/or pain
What are the three basic steps to a small ruminant hoof trim?
-tip of the claw
-reduction of abaxial wall
-reduction of axial wall
What is the primary goal of hoof trimming in small ruminants?
create a flat surface for walking
What are the clinical signs of lameness in small ruminants?
-recumbent/unwilling to stand
-walking on their knees
-abnormal gait/limping
-swelling
What are the characteristics of small ruminant interdigital dermatitis?
-aka foot scald or benign foot rot
-opportunistic infection predisposed by moisture and trauma
-caused by Fusobacterium necrophorum
What are the clinical signs of small ruminant interdigital dermatitis?
-skin redness
-swelling
-erosion
-lameness
-pitting of heel horn
What are the characteristics of small ruminant foot rot?
-caused by Dichelobacter nodosus
-gram neg. anaerobe
-obligate parasite of skin of feet; will die if away from host 1-2 weeks
-can have asymptomatic carriers
-more common in sheep than goats
-Fusobacterium necrophorum may be present but does not iniiate infection
What are the predisposing factors for small ruminant foot rot?
-warm temps and high humidity
-co-mingling
-new arrivals without quarantining
-hard, high grass
What are the clinical signs of small ruminant foot rot?
-lameness across multiple legs and in both claws per limb
-necrotizing inflammation of interdigital skin
-pain
-foul/necrotic odor
-separation of horn from underlying tissues
How is small ruminant foot rot controlled?
-trimming
-foot bath
-antimicrobials (lots of labelled drugs)
-culling if severe
-preventing moisture and trauma
Which drugs are labelled for small ruminant foot rot?
-procaine penicillin
-oxytetracycline
-draxxin
What are the characteristics of footvax?
-contains Dichelobacter nodosus and adjuvant
-labeled for sheep with a 0 day meat withdrawal
-varying efficacy in studies
-considered for large herd/producer systems
What are the characteristics of small ruminant foot abscesses?
-can be acute or chronic
-secondary to interdigital dermatitis or trauma
-cause severe swelling
What are the treatment options for foot abscesses?
-establish drainage of purulent discharge
-antibiotics if deep/extensive and approaching tendons
-bandages
-amputation of digit if severe
What are the characteristics of septic arthritis?
*origin:
-traumatic wound
-untreated/uncontrolled foot rot
*location:
-primarily distal interphalangeal joint
*diagnosis:
-rads
-joint tap
*treatment:
-antibiotics
-surgery
*prognosis:
-guarded
What are the characteristics of caprine arthritis encephalitis virus?
-disease of small ruminants and camelids
-RNA-enveloped lentivirus that targets macrophages and monocytes
-causes encephalitis in young animals and arthritis in old animals
What are the characteristics of CAE transmission?
-can occur through colostrum; must remove kids before feeding in known infected mothers
-horizontal transmission can occur at any age; danger with co-mingling and new animals
What is the pathophysiology of CAE?
-20% of animals display clinical signs
-polysynovitis-arthritis is most common form in older animals
-joints are enlarged and painful
-hyperplasia of the synovial tissues occurs; NOT synovial fluid
What are the clinical signs of CAE?
-stiffness
-stilted gait
-carpus walking
-reluctance to stand
-joint contracture
How is CAE diagnosed?
-joint tap joint tap showing increased mononuclear cells and decreased protein
-rads showing soft tissue swelling, calcification, and osteophyte presence
-ELISA blood test to detect CAE antibodies in goats older than 6 months (most common)
What is Mycoplasma associated with in goats?
-pneumonia
-mastitis
-polyarthritis
Why is it important that Mycoplasma do not have cell walls?
-allows them to invade immune system
-cannot be treated with beta-lactams
What are the characteristics of Mycoplasma mycoides subsp. capri?
-causes polyarthritis in young kids
-can be associated with infected mammary gland of dam
What are the clinical signs of mycoplasma associated lameness?
-rapid onset of lameness
-swelling over joints, esp. carpus
-similar presentation to CAE
What is the treatment for mycoplasma associated lameness?
antibiotics that do not target the cell wall; variable prognosis
What are the characteristics of laminitis in small ruminants?
-common
-originates from lush pasture or too much grain
-signs include knee walking, stiffness, warm feet, and toe tipping upwards
-treated with pain management, diet management, and euthanasia if severe
What are the characteristics of rickets?
-disease that affects all species
-only in young, growing animals; disease of growth plates
-leads to angular limb deformity
What can cause rickets?
-insufficient phosphorus or calcium intake
-inappropriate calcium:phosphorus ratio (ideally 2:1)
-lack of vitamin D
What is the prevention/treatment for rickets?
-appropriate diet and intake
-access to sunlight
-supplementation of vitamin D
*good prognosis
What are the characteristics of white muscle disease?
-degenerative muscle disease caused by vitamin E/selenium deficiency
-affects newborns and fast growing animals
-occurs in selenium deficient soils/regions
What are the characteristics of enzootic ataxia?
-neurodegenerative dz
-symmetric loss of myelin
-due to copper deficiency
-congenital form occurs if doe has decreased copper intake during pregnancy
-kids are born with tremors and weakness and die quickly
-delayed onset can occur at 2 to 4 months of age
What are the clinical signs of enzootic ataxia?
-“swayback”
-uncoordinated movements
-“dog sitting”
What are the consequences of enzootic ataxia?
kids:
-irreversible signs
copper deficient animals:
-anemia
-long bone fractures
-weight loss
-poor hair coat
What are the ways in which developmental lameness can occur?
-abnormal angulation of limb
-bone and/or tendon involvement
-congenital vs acquired
How does a valgus ALD differ from a varus ALD?
*valgus:
-carpuses angled in
-feet angled out
-more common
*varus:
-carpuses bowed out
-feet angled in
-less common
What are the correction options for ALD?
-stall rest if less severe
-surgical correction if severe; transphyseal bridging or wedge ostectomy
What are the causes of contracted tendons?
-more commonly congenital than caused by misuse
-can be secondary to previous lameness lameness/injury
How does the prognosis differ based on cause of contracted tendons?
-previous lameness/injury carries a poor prognosis due to joint capsule fibrosis; can still attempt surgery
-congenital forms can be treated with splints and/or tenotomy and pain control and usually have a good prognosis
What are the clinical signs of fractures in small ruminants?
-standing still
-non-weight bearing lameness
-quivering/vocalizing/grunting/other signs of pain
-dangling leg
-swelling at area
-crepitation
What are the characteristics of external coaptation for fractures?
-want a fiberglass cast that inhibits flexion/extension of the 2 adjacent joints and stabilizes them
-must incorporate entire foot into cast since they weight bear on P3
-want firm bandages and splints
What is the prognosis for fractures?
-excellent prognosis for closed fractures
-open fractures require race against infection; need lots of lavage and antibiotics
What are the characteristics of animal attacks on small ruminants?
-common
-prognosis varies with involved structures
-dogs often go after throat, ears, and limbs
What is the treatment for animal attack wounds?
-clip, clean, and lavage
-debridement
-antibiotics
-NSAIDs/opioids
-tetanus vx
-euthanasia if severe
What are the characteristics of spider lamb syndrome?
-genetic; autosomal recessive disorder in which fibroblast GF Rc is mutated
-excessive skeletal growth
-carriers are not clinical and hard to detect
-black faced sheep breeds often affected
-signs present at birth or soon after
-no treatment; humane euthanasia
-genetic testing mostly prevents it in US
What are the characteristics of corn/interdigital fibroma?
-not as common as in large ruminants
-secondary to trauma, severe foot rot, or foreign body
-surgical removal if causing lameness or ulcerated
-want to remove inciting cause
