Porcine farm visit
St. George’s University School of Veterinary Medicine, for the past nine years, has been
assisting livestock farmers throughout Grenada with animal husbandry, management practices,
nutrition, clinical applications, and surgery. These visits are conducted by the University
Ambulatory Clinician and the sixth term students.
During these visits, many abnormalities among farm-producing animals are encountered.
Recently, we visited a porcine farm where several piglets were housed in a clean pen. In this
pen, a 3-month old female duroc piglet was observed with deformities of the hindlimbs which
were bilateral in nature. The history indicated that the animal was born with the deformities.
Upon observation, the animal was in good physical condition except that both hindlimbs were
small and not fully developed. In addition, the limbs were anatomically located under the caudoventral part of the abdomen with bilateral hyperflexion and abduction of the femorotibial joints.
Also the tarsometatarsal joints were hyperflexed and adducted. (See photo).
The forelimbs of the animal were normal and the animal stood squarely on its forelimbs. The
muscles, tendons, ligaments and boney structures of the forelimbs were well-developed. (See
photo).
The animal ambulated in any direction utilizing its forelimb effectively while the hindlimbs,
caudo-ventral abdomen and perineal regions dragged along. Therefore, the forelimbs propelled
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the animal forward while the rest of the body followed. In spite of this method of locomotion,
there were no abrasions on the skin of the hindlimbs or other areas which were in contact with
the ground surface. However, the skin of these areas was somewhat dark and hypertrophic.
Palpation of the hindlimbs revealed that they were underdeveloped with small bones and
immovable joints and corresponding atrophic muscles.
In spite of these deficiencies, no special attention or consideration was given to this animal. As a
result, the animal learned to survive and compete for food quickly and effectively.
The cause of the condition in this piglet is speculative. For example, it may be due to:1. Malposition of the hindlimbs in utero.
2. Lack of development or underdevelopment of both hindlimbs (AMELIA). The etiology
is unknown and the frequency of occurrence is rare. Diagnosis is based solely on
physical examination.
3. Perosomus elumbis: agenesis of the caudal parts of the body; the hindlegs were fixed in
arthrogryposis, the spine ends at the thoraco-lumbar area. The diagnosis was based on
physical examination. Radiographic examinations would have been beneficial to confirm
the diagnosis.
4. Arthrogryposis: This condition results in the fixation of joints and is due to a number of
different causes but is frequently teratogenic in origin.
5. Congenital hemimelia: piglet with varying degrees of tibial hypoplasia. This condition is
congenital in nature.
6. Atypical “splayleg” of the hindlegs: This condition is presented as an inability of piglets
to use its hindlegs so that it assumes a “dog-sitting” position with both hindlegs alongside
the body and not laterally as in true splayleg.
7. Congenital articular rigidity: This involves the immobilization of the joints. It may be
due to the lack of extensibility of muscles, tendons, ligaments, or other tissues around the
joints. It could have been deformity of the articular surfaces or due to fusion between the
bones at the articular surfaces.
Muscle contracture is usually the principal cause of joint fixation. It occurs naturally as a result
of atrophy resulting from denervation. In pigs, inherited congenital articular rigidity can also
result from nutritional deficiency of Vitamin A. It can also be the result of poisonous plants such
as hemlock, Jinson week and tobacco waste.
Currently, there are no recommended treatments documented for the above condition in this
piglet except slaughter for home consumption. Many possible causes were listed; however, it is
generally felt that the condition is more of a congenital nature or atypical splayleg.
Submitted by: Buxton Nyack, DVM
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