Lecture 20 3/25/25 Flashcards
Which methods allow for adequate restraint for hoof trimming?
-claw trimming chute
-rotating chute
-tilt table
What are the characteristics of using ropes and poles for hoof trimming restraint?
-subadequate restraint
-can be very difficult; not ideal when working with tools
-often the only way to restrain animals for trimming in the field
Which sedative drugs can be used for hoof trimming?
-xylazine
-acepromazine
-ketamine stun (ketamine, xylazine, butorphanol)
What are the general characteristics of the claws?
-normal horn grows at a rate of 5 to 7 mm a month
-natural wear depends on flooring, humidity, conformation, and underlying lesions
-lateral rear claws are usually bigger; more horn produced at the weightbearing claws
-overgrowth mainly seen at toe
-horn is very solid and doesn’t wear well
Why is horn overgrowth at the toe common?
horn of the wall at the toe is harder than at the heels and does not wear as easily
What are the characteristics of heel overgrowth of the rear lateral claw in beef and dairy cattle?
beef: sole tends to slop more
dairy: flat bearing surface due to mechanical wear on concrete
What are the consequences of horn overgrowth?
-step between the wall and sole
-weight shifts towards center of hoof
-excessive pressure is applied to corium
What are the goals of claw trimming?
-correction of overgrowth
-balance weight bearing within/between claws
-early detection and correction of lesions
What is the ideal schedule for claw trimming?
dairy: twice a year
beef: varies with season, amount of wear, and individual
How can claw trimming cause lameness?
-overtrimming
-thin soles
What is the caution taken with pregnant cows and claw trimming?
cows should not be placed on their side if they are 5+ months pregnant due to risk of uterine torsion
What are the steps of cleaning/inspection prior to claw trimming?
-rinse off any dirt/debris to accurately assess hoof
-examine the coronary band
-flex and extend each digit
-inspect interdigital space
-palpate palmar/plantar area
-look for pathological lesions
-apply hoof tester to toe and areas where ulcers may form
-assess for pain, swelling, and odor
What are the ideal claw dimensions?
-3 inches of wall from coronary band to toe
-1.5 inches of heel high at the abaxial groove
-5 to 7 mm sole thickness
How does the thickness of the sole vary?
anterior part of the sole is thinner than at the heel
How is the sole handled during trimming?
very rarely does the sole need to be touched during a preventive trimming; should be left alone to prevent thin soles
What are the 4 steps to a functional trim?
-address toe length and sole thickness of the medial claw
-address toe length and sole thickness of the lateral claw
-slope the interdigital space
-balance the heels
What are the steps to trimming the toe?
-measure the dorsal wall of medial claw
-identify 3 inches
-trim any excess; follow the angle of the toe
What are the steps to correcting sole thickness when trimming?
-ensure at least a 1/4 inch thick
-preserve heel and remove sole at the toe
-white line reconnects at toe; leave sole intact from heel to toe
What is the consequence of a long toe?
weight bearing is transferred to the posterior region of the clow and the pedal joint is overextended
What are the cuts made when correcting the toe?
-first cut to remove excess toe horn
-grinding to flatten the horn in line with the hoof
What must be accounted for regarding the dorsal wall of the hoof when trimming?
-accurate measurement of the toe cannot be done if the dorsal wall is not straight
-dorsal wall should be straightened before correcting toe length
What is important about trimming the lateral claw in step 2?
-the trimmed medial claw should serve as a guide
-the heel may need to be lowered to level with the medial claw
What are the goals of sloping the interdigital space?
-reduce pressure on common sole ulcer sites
-open the interdigital space
What are the guidelines for sloping the interdigital space?
-start at level of abaxial groove
-preserve toe
-work at a 45 degree angle
-remove no more than 1/3 of the length between the abaxial and axial walls
What is the goal of balancing the heels?
ensure appropriate distribution of weight within and between the claws
What are the characteristics of corrective trimming?
-goal is to offload weight from the diseased area
-all loose horn must go; it traps dirt and bacteria and does not contribute to weight bearing
-want to keep the toe triangle intact when possible
What are the characteristics of claw blocks?
-claw must be dry and leveled prior to application
-must align with axial wall
-must align with heel
-can be removed once healing occurs
-very helpful at alleviating pain, esp. when combined with pain medication
Why are wood blocks Mulon’s choice?
wood blocks wear down over time and allow the cow to progressively bear weight on the injured toe
Why is it very important that the claw block aligns with both the axial wall and the heel?
-alignment with the axial wall prevents the block from interfering with the other claw
-alignment with the heel prevents excessive strain on the tendons
Why are rechecks on claw blocks done at 4 weeks?
4 weeks is the amount of time needed for a lesion of the claw to heal
What are the common hoof trimming mistakes?
-trimming dorsal wall too short
-removal of too much horn from heel of rear inner claw
-trimming of inside toe/axial wall
-sloping the sole/creating concave weight bearing surface
-trimming of dorsal wall at the toe
-excessive trimming at sole/creating thin soles
What are the downsides of bandages?
-can have negative effects if not done properly
-should not be too tight; can cause ischemia
-can absorb manure-contaminated water if not kept clean
-can get soaked in footbath solution and cause irritation
-must be changed every 2 to 3 days
What are the indications for a bandage?
-too much exposure of the corium
-bleeding
-infectious skin disorders
When is a bandage NOT indicated?
-small corium exposure
-owner will not be able to remove/recheck
What are the characteristics of dexamethasone?
-used topically
-inhibits wound healing
-reduces fibrosis
-reduces neovascularization
-contraindicated if there is prolapsed corium
Why is oxytetracycline powder only used for digital dermatitis?
it burns the corium and can prevent healing
When should animals be referred for corrective hoof trimming?
-lack of appropriate facilities
-possible joint/tendon sheath involvement
-very demanding aftercare
