Splay leg


Causal agent

Environment, genetic and mycotoxins

Other names

Straddlers, Myofibrillar hyoplasia

Age group

Piglets within hours of birth.  Males more affected

Clinical signs


Piglet shortly after birth has splayed back and occasionally front legs.  The effect seriously affects the piglet’s ability to dry, suckle and get out of the way of the sow, therefore pre-weaning mortality is increased




None. The disease only affects individual



sow slipping in the farrowing house

Environmental – slippy floors especially behind the sow

Piglets staying wet and cold too long

Low birth weight piglets

Stressed sows at farrowing more prone to deliver splay leg piglets

Zearalenone (F2) toxin may be associated with increased incidence

In some cases there is a genetic component to the problem – Landrace more common than in Large White

Post-mortem Lesions


Hypoplasia of the muscles of the back – longissimus dorsi and the biceps femoris muscles



Clinical signs very characteristic




If all four legs euthanase piglets

If hind legs only affected, tape legs together

Massage hip area of the affected piglet

Provide support for the back legs using tape and bands.   Do not apply too tight to cause circulation constriction. Remove as soon as possible- after 48 to 72 hours



Doubled elastic band held between the hind legs.  Tape over the back may  help stabilise the back as well

What ever treatment is pursued, it is essential to provide adequate colostrum within 6 hours of birth


Repair or replace farrowing house floor in particular behind and sides of sow

Paint floor with lime wash to increase adhesive properties of floor



Rear of crate lime washed

Sow too large/long

Farrow piglets in the passageway behind the sow to allow a dryer and cleaner environment

Place mats or feedbags behind the sow during farrow

Review gestation feeding.  Increase feed intake from day 90 to 110 of gestation.  Birth weights need to be greater than 1.2 kg

Reduce gestation stress.  Place sows into farrowing house at least 5 days before farrowing.  Ensure sow housing adequate – length of sides, floor no draughts etc

Do not breed from splay leg gilts or boars.   While the animal recovers permanent damage may have been incurred

Common differentials


Spinal injury.  Trodden on by sow