sheep dytocia

History

Most common cause – malpresentation

·    Is birth premature or overdue? – if overdue = foetus likely to be large, if premature = likely to be abortion

·    Has the dam given birth before? Any complications?

·    How many lambs?

·    BCS of dam?

·    What has recently been noticed in the dam?

o  Uterine +/- abdominal contractions?

o  Vulval discharge?

o  Straining?

·    Have any foetal membranes/fluid been expulsed? Any foetal parts seen? Evidence of foetal life?

·    How long has she been straining for?

General clinical exam

·    Is she BAR, or dull?

·    BCS?

·    Is she able to stand and walk?

·    TPR

·    Any foetal parts visible at vulva? What foetal parts?

·    Vulval discharge present? Colour?

·    Abdominal distension?

Evidence of foetal life? – suckling, withdrawal reflex in utero, foetal pulses

Vaginal exam

·    Is vestibule dilated?

·    Is caudal vagina dilated?

·    Cervix open?

·    How lubricated is the tract?

·    If foetuses present, are they alive?

·    What is the foetal position, presentation and posture?

·    What is the relative size of birth canal? – likelihood of foetuses being delivered?

Any lacerations present?

Treatment options

·    Conservative treatment – is it just the dam just not ready to give birth yet?

·    Manipulative treatment – lots of lube, consider using tocolytic agents + oxygen for foetus

·    Drug therapy

o  Induce contractions with oxytocin (ecbolic)

o  Supplement Ca – as low Ca could be causing poor contractions

o  If labour premature – can reduce contractions and postpone labour with clenbuterol (tocolytic)

·    Surgical treatment

o  Epidural anaesthesia

o  Episiotomy – incision at 10 and 2 o’clock, widens opening to allow easier passage of foetus

o  Fetotomy – if foetus already dead

o  Caesarean – indications: foeto-maternal disproportion, breeched, malpresentation uncorrectable (not recommended if calf decomposing ® peritonitis risk)

·    Euthanasia

Causes

·    Most common cause: malpresentation

·    Maternal causes:

o  Inadequate expulsive forces: uterine inertia, weak abdominal straining

o  Inadequate size of birth canal: incomplete dilation or constriction of birth canal, inadequate pelvis

·    Foetal causes:

o  Oversize: relative/absolute, congenital monsters, foetal pathology – C-section, fetotomy

o  Foetal disposition: presentation, posture, position – usually correctable by manipulation

Consequences

·    Reduced welfare for both dam and neonate

·    Reduced production

·    Stillbirth, dam death

·    Increased risk of post-partum problems, e.g. metritis, RFM