topics in equine and large animal practice

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Topics in Equine and Large Animal Practice

New Foal Examination

Laurie Gallatin DVM, DACVIM

laurie.gallatin@pennfoster.edu

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Preparing for the Foal

• 340+/- days gestation

• 3 stages of labor

• Preparations begin at least 1 month prior- pre-foaling vaccines (colostrum)

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Prepartum Vaccinations to Protect the Foal

• 1 month prior to expected foaling date: – F/R, EWT, WNV, PHF, +/- botulism

• 8,9, and 10 months of gestation:– Rotavirus

• 5, 7, 9 months of gestation:– EHV- 1 and EHV- 4

• Regular deworming schedule and W/I 24 hours of foaling

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Stage 1 Labor• Can last up to 12

hours.• Mare may be

restless• Up and down• Urinating

frequently• Ends when

allantois breaks

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Stage 2 Labor

• Expulsion of the foal.

• Occurs within 30 minutes of water breaking.

• If not- EMERGENCY!

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Stage 3 Labor

• Begins once foal is out.

• Expulsion of Placenta

• Should occur w/in 3 hours of foaling.

• If not- EMERGENCY!

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New Foal Examination normally performed at 12-24

hours of age.

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New Foal Examination(Foal-O-Gram)

• Cardiovascular• Respiratory• Urogenital• Umbilicus• Musculoskeletal• Ophthalmic• Digestive• Neurologic• Hematologic• Immunologic

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Foal Restraint

• ALWAYS have someone hold the mare.

• Keep the foal between you and the mare

• Wrap arms around foal

• Use walls

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Periparturent Mare Examination

• Check:– Udder– Vulva– Placenta

• Completeness

– Deworm– +/- Oil

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Cardiovascular System• Rate begins at 40-80,

then elevates to 120-150• drops to 80-100 by 1

week

• Rhythm – sinus arrhythmias WNL

• Other arrhythmias occasionally- significance depends on other clinical signs.

• Murmurs- holosystolic murmur - common - probably physiologic - not PDA

• PDA - normal up to 7-10 days - unless other signs of disease

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Respiratory System

• Rate- 60-80 breaths per minute at birth

• declines to approximately 30/minute within 1 hour

• very loud lung sounds - normal

• may hear slight crackle in ventral lung fields

• increased effort - flared nostrils, abdominal component to respiration more important than auscultation

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Respiratory System

• palpate thorax for rib fractures• brown tinged nasal exudate -

mechonium aspiration• milk from nose - cleft palate• diagnostic aids– ultrasonography - hernia, hemothorax– radiographs

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Urogenital System

• Colts - both testicles usually descended at birth

• inguinal hernia - particularly Standardbred - correct by manual reduction several times each day for first few days of life

• Colts -ruptured bladder - may strain to urinate and only pass small amounts at short intervals

• tail elevated and back hollowed out

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Umbilicus• Dip umbilicus• normally a small defect 4-8 cm in the

body wall is present at birth• usually closes within 2-3 days• draining urine - patent urachus• enlargement of umbilical stalk -

possible infection• ultrasound of umbilicus easy method

to detect problems

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Musculoskeletal System• Angular limb

deformities– Valgus/ Varus– Collapsed

carpus/tarsus– "Windswept”

• Axial skeleton– Scoliosis– Lordosis– kyphosis

• Contractural deformities– superficial/deep flexor

tendons– joint capsule/septic

joints

• Physeal injuries• Brachial plexus injuries• Gastrocnemius rupture• Luxations

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Musculoskeletal System

• skull deformities• "Wry" nose• miniature foals

appear hydrocephalic

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Ophthalmic Exam

• Eyelids– Entropion

• Eye– cornea - ulcers – lens - suture lines,

persistent hyaloid– retina -

detachments, vascular disruptions to optic disc

• Anterior chamber– hyphema– Hypopion

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Digestive System• mechonium passage is

crucial - must occur within first few hours

• signs of difficulty– straining with tail

elevated and back arched

– short, frequent attempts to nurse

• auscultation - sounds every 20-30 seconds

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Digestive System

• percussion - find gas filled areas of intestine

• ultrasonography/radiography• nasogastric intubation - difficult in

some cases since foal may have a depressed swallowing reflex

• abdominocentesis

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Neurologic System• vestibular system• ocular reflexes -

normally slower than in adult, menace may be absent

• swallowing reflex• foals are hyperreflexic

to stimuli until several weeks old

• gait - ataxia, circling• abnormal

vocalizations

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Hematology

• values for hemogram and profile are significantly different from adult for first few weeks– Creatinine– GGT– ALP– etc

• neonatal icterus common - check for neonatal isoerythrolysis

• muscle enzymes frequently elevated to some degree

• Evaluate CBC including WBC, PCV, and TP at new foal exam

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Immunologic System

• IgG - measure 18-30 hours after birth

• agammaglobulinemic d/t epitheliochorial placentation

• Must receive 1-2 pints high quality colostrum within 12 hours of birth (3,000 mg/dl IgG = SG of 1.050)

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Evaluation of the Immunologic System

• Methodology - tests for passive transfer– ELISA for equine IgG– radial immunoassay - standard for

comparison– ZnSO4 turbidity– sodium sulfite– glutaraldehyde– agglutination reactions

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Immunologic System

• > 800 mg/dl – normal

• >400 but <800 mg/dl - partial failure transfer

• <400 mg/dl - failure of passive transfer

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Immunologic System

• Treatments for FPT or PFPT– Colostrum – oral- if

< 12-24 hours old– Equine serum - oral– Lyophilized IgG -

oral– IV plasma transfer -

only option after 18-24 hours

Septicemia is the number 1 cause of death in foals under 7 days of

age!

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Vaccination Guidelines

• Recently (2008) set forth by AAEP Infectious Disease Committee and can be viewed on the AAEP website.

• www.AAEP.org

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