Large Animal �VTNE

Amanda Hackerott, RVT

My VTNE Tips

PREPARATION

• Scientific names
• Gestation times
• Drugs
• Variety of resources

TEST DAY

• Go with your gut
• Power of deduction
• What is it really asking you?
• Superman pose
• Visualization

My Favorite VTNE Resources

• Mosby's
• Illustrated Veterinary Medical Terminology
• McCurnins aka the bible
• Pocket Prep app
• Youtube

Game Plan

Disclaimer

Large Animal Anatomy

• Poll: top of head
• Withers: top of shoulder
• Pins/Hooks: BCS
• Paralumbar fossa: laparotomy site
• Heart girth: measured for wt estimate

Large Animal Anatomy

1. Rumen- microbial fermentation
• paunch
2. Reticulum- microbial fermentation
• honeycomb
3. Omasum- water absorption
• "Many folds/pages"
4. Abomasum- glandular
• True stomach

Large Animal Anatomy

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• Rumination
1. Regurgitate
2. Remasticate- chew
3. Resalivate
4. Deglutition- swallow

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• Eructation- burping
• Borborygmi- gut sounds

Large Animal Anatomy

https://opensanctuary.org/horse-anatomy-the-hoof/

• Coronet aka coronary band: where the hoof grows from

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• Hoof trim q 6-8 weeks (shod)

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Large Animal Anatomy

• Frog: distributes impact, traction
• sensitive

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• White line: sole connects to wall

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• Bar: shock absorption

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Large Animal Anatomy

• Hindgut fermenters
• Cecum- can hold 7-9 gallons
• Haustra

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• Can't vomit
• Limiting ridge of esophagus
• Strong cardiac sphincter

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• Colic- GI pain
• Medical or surgical tx

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Large Animal Anatomy

Large Animal Anatomy

TOXIC LINE

HEAVE LINE

Large Animal Anatomy

• Epistaxis
• Guttural pouch infx
• Exercise induced pulmonary hemorrhage
• NGT

Large Animal Anatomy

• Wolf tooth: upper PM1
• Facial artery
• IM injection triangle

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Large Animal Anatomy

Large Animal Anatomy

• Sebaceous glands
• Lanolin

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• Rumping (handling)

Large Animal Anatomy

• Cranial vena cava
• R side avoids phrenic nerve

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• Note the snare location on maxilla!

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Large Animal Anatomy

• Needle teeth
• Difficult to intubate
• LOUD!!!

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Large Animal Anatomy

• Protect the neck!
• Use semis, quads or triceps for IM

Large Animal Gestation Times

• Bovine: 271-291 days (9 months)

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• Equine: 321-346 days (11 months)

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• Ovine: 143-151 days (5 months)

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• Caprine: 146-155 days (5 months)

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• Camelid: 335-345 days (alpaca), 330-360 days (llamas)

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• Porcine: 110-116 days (3 months, 3 weeks, 3 days)

Large Animal Pathology

• Strangles: Streptococcus equi equi
• Highly contagious
• Fever, anorexia, depression, mucopurulent nasal d/c, abscess LN
• Vaccinate
• Quarantine new horses

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• EIA: biting flies; Coggins test annually
• + cases must quarantine for life or euth
• Reportable
• Blister beetle toxicity: Cantharidin tox; contaminated hay

Large Animal Pathology

• West Nile Virus: core vaccine, environmental control of mosquitoes

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• EEE/WEE/VEE: core vaccine, "sleeping sickness"

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• Rabies:
• Furious form: hyperexcitability, fear, rage
• Dumb form: extreme depression, paresis, paralysis
• Zoonotic
• Wear PPE, especially when oral exams

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Large Animal Pathology

• Lyme disease: Borrelia burgdorferi
• Tick borne (Ixodes)
• ELISA test
• Doxycycline

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• Sarcoids: most common tumor in horses (cause unknown, maybe viral?)
• Melanomas: common in gray horses, in hairless areas
• PPID: aka Cushings; >15yr; long, curly coat (hirsutism)

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Large Animal Pathology

• Anthrax
• Bacillus anthracis
• Spores remain in environment
• Zoonotic
• Reportable
• Peracute- sudden death
• Acute- staggers, seizures, death
• Vaccinate
• Do not necropsy!

Large Animal Pathology

• Johnes (yo-knees) disease
• Mycobacterium tuberculosis
• Diarrhea, wt loss
• Can be subclinical shedder
• Control programs: repeated serologic and fecal testing, cull +

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• Bovine Respiratory Disease Syndrome (BRDS)
• "shipping fever"
• Complex bacterial, viral and stress induced
• Primarily feedlot calves, and dairy calves <6mon

Large Animal Pathology

• Milk fever: late pregnancy/early lactation
• Aka hypocalcemic parturient paresis

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• Mastitis: Streptococcus agalactae or Staphylococcus aureus (contagious)
• CMT: done before routine milking or 6hr post milking
• Clean in order of far to near (with alcohol, let dry)
• 1st stream discard
• Collect near to far
• Rotate paddle gently; score 0-4 based on precipitate formation

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Large Animal Pathology

• White Muscle Disease
• Vit E & Selenium deficiency
• Cardiac- severe debilitation/sudden death
• Skeletal- weakness/stiffness/recumbent

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• Ruminal tympany- bloat
• Froth or obstruction
• Trocar/cannula @ L paralumbar fossa
• Ruminal acidosis- grain overload
• Lactic acid increases, lowers the pH of rumen contents
• Emergency!

Large Animal Pathology

• Left Displaced Abomasum (LDA)
• Large frame dairy cows after calving
• High grain diet
• General GI signs

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• Right Displaced Abomasum (RDA)
• EMERGENCY! Due to torsion risk
• Post calving
• Less common than LDA
• Acute, severe pain; toxicity; death

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• AVMA estimates ~200,000 displaced abomasum in dairy cow annually

Large Animal Pathology

• Vibriosis
• Campylobacter fetus
• Zoonotic
• Spread thru infected bull
• Contaminated food/water (sheep)
• Infertility or stillbirths (lambs)
• Vaccinate!

Large Animal Pathology

• Brucellosis
• Brucella abortus
• Zoonotic--> undulant fever in humans
• Reportable
• "Bangs" vaccine
• Only handle by federally accredited DVM
• Tagged and tattooed
• Listeriosis
• Listeria monocytogenes
• Zoonotic
• Commonly found in ruminants; in sheep aka circling disease
• Bacterin available!

Large Animal Pathology

• Leptospirosis
• Leptospira pomona
• Zoonotic
• Urine and abortus
• Live in environment for weeks to months
• Vaccinate!

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• Trichomoniasis
• Trichomonas fetus- protozoan STD
• Asymptomatic in bulls

Large Animal Pathology

• Bluetongue
• Sheep
• Culicoides cause
• Crusty lesions of nose, oral cavity lesions

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• Anaplasmosis
• Anaplasma marginale
• Insect & arthropod vectors
• Calves get subacute form- fever- may die- survivors compromised fertility
• Acute cases can attack caretaker
• Peracute usually die within 24hrs (after fever/anemia/resp distress)

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Large Animal Pathology

• Pinkeye
• Infectious bovine keratoconjunctivitis
• Moraxella bovis
• Flies as vector

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• Foot rot
• Fusobacterium necrophorum

Large Animal Pathology

• Ketosis
• Aka acetonemia in cows
• Pregnancy toxemia in everyone else
• Acetone breath, milk, urine
• Wasting or neuro
• Tx with glucose

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• EAE: Enzootic abortion in ewes; vaccinate!
• Chlamydophila abortus
• Last trimester abortion/stillbirth/placentitis

Large Animal Pathology

• Caseous lymphadenitis:
•  Corynebacterium pseudotuberculosis
• Highly contagious
• Goats: external abscesses
• Sheep: internal abscesses
• Cull

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• Contagious ecthyma
• "Orf" /"sore mouth"
• Zoonotic
• Poxvirus
• Self limiting, resolves 3-6 weeks

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Large Animal Pathology

• Copper toxicity:
• Sheep>goats
• Accumulates in the liver and stress/shipping/handling releases the copper--> acute hemolytic crisis

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• Scrapie:
• Prion- spongiform encephalopathy
• Wt loss
• 2-5 yrs of age

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Large Animal Pathology

• Atrophic rhinitis
• Bordetella bronchiseptica or Pasteurella multocida
• Sneezing, nasal d/c, distortion of nose, epistaxis
• Pseudorabies
• Aujeszky's disease; herpes virus
• Fever, depression, v, paddling, recumbency, death w/in 12hr
• Vaccine!
• Meningitis
• Streptococcus suis
• Fever, stiff gait, tremors, ataxia, recumbency, paddling, death

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Large Animal Pathology

• Erysipelas (Erysipelothrix rhusiopathiae)
• Zoonotic
• Acute: fever, anorexia, diamond shaped skin lesions
• Chronic: arthritis or vegetative endocarditis

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• Pig parvo

Large Animal Pathology

• Diarrhea
• E. coli
• Salmonella
• Rotavirus (small ruminants)(pigs)
• Swine dysentery (Treponema)
• Clostridium perfringens type A (camelids)
• Eimeria spp (your herbivore coccidia)
• Bovine viral diarrhea (BVD)- can also see respiratory disease

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• "Scours"

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Large Animal Pathology

• Clostridium tetani
• Always check status before surgery/dehorning
• Vaccinate annually

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• Clostridium perfringens/difficile
• Bacteria that produces toxins
• Overgrowth of difficile is most common cause of abx associated diarrhea

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• Clostridium botulinum
• Contaminated feed, infected wounds

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• Clostridium chauvoei
• Blackleg (cattle)

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Large Animal Pharmacology

• Frick speculum: guide for OGT
• OGT: measure tip of nose to last rib
• Drenching: small amounts of liquid
• Vitamin B, C, D, E
• Copper
• Magnesium

Large Animal Pharmacology

• Lidocaine: local anesthetic, analgesic
• Xylazine: alpha 2 agonist
• cattle are sensitive; use 1/10th the dose for horses

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• Ketamine: dissociative
• Guaifenesin: anesthetic adjunct

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• Phenylbutazone: "Bute", NSAID
• Flunixin: Banamine, NSAID

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Large Animal Pharm

• Blocks
• Line
• Field: L block used in flank
• Ring: used in foot/hoof work
• Regional IV block: tourniquet used, inject below
• Epidural: usually at sacrococcygeal space

Large Animal Surgery- Equine

• Recovery most dangerous period
• PADDDDDDDDDDDING! To reduce neuropathies/myopathies

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• Dorsal: pad the poll/shoulders; back legs left natural
• Lateral: leave head natural, the down front leg pulled forward

Large Animal Surgery- Bovine

• Keep cuff inflated during extubation
• Recover sternal if possible 
• Right lateral otherwise (keep rumen up)

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• Laparotomy: LDA/RDA, c section, rumenotomy
• Standing in chute or stocks with local anesthetic

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• Cornual block: dehorning
• Peterson eye block: enucleation
• Ring block: teat sx, dehorning, claw amputation

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Large Animal Surgery- Small Ruminant/Camelids

• Keep cuff inflated during extubation (both)
• Eye position for depth is not accurate (small ruminants)

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• Keep nose lower than pole to prevent aspiration or nasal edema (camelids)
• Recover in sternal recumbency

Large Animal Surgery- Porcine

• Beware of potential malignant hyperthermia
• Porcine Stress Syndrome
• Pietrain and Landrace breeds more susceptible
• Dantrolene

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• Castration at 1-2 weeks; using open technique
• Same time give iron, clip teeth and tail

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Large Animal Bandaging

Thomas Splint/Cast

Large Animal Species by Species Weirdness- Equine

• "Bagging up": indicates foaling; udder swells/fills with milk
• Galvayne's groove: used to age horse—teeth marking
• Guttural pouch: extension of the eustachian tube
• Casting: use of ropes to force recumbency
• Asthma: aka RAO (recurrent airway disease)
• Laminitis (founder): severe hoof pain, check digital pulses as part of PE
• Navicular bone: boat shape; distal sesamoid
• Equine recurrent uveitis: "moon blindness"; immune mediated
• Nuclear scintigraphy: bone scan, Technetium- 99

Large Animal Species by Species Weirdness- Bovine

Large Animal Species by Species Weirdness- Porcine

• Intubation difficult
• Small oral cavity
• Long/mobile larynx; spasm is common
• Pharyngeal diverticulum
• Difficult to visualize
• Consider v gel

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Other Random Information

• Identification
• Cattle
• AS: farmer's tags
• AD: regulatory/government
• Goat/Sheep
• AS: farm ID
• AD: scrapie tag
• Pig
• AS: notches indicate pig's birth # within breeding season to sow
• AD: notch indicates pig litter #

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I hope this helped!!!

https://www.youtube.com/@freestatervt7932/videos