Trichuris suis: Whipworm

General Description: This worm gets its common name because of its whip-like appearance. The anterior two-thirds of the body is slender and thread-like, while the posterior third is much thicker. The tail of the male is coiled; that of the female is straight. Adults may be 5 cm. Long.

Life Cycle: The yellowish-brown eggs are barrel-shaped and smooth with a clear plug at each end. These are shed in the faeces and are infective after 3 weeks or more, at which time first-stage larvae have developed within the eggs. Infective eggs may remain viable for several years on vegetation or in the soil. After being ingested by pigs, the eggs hatch. The whipworm larvae enter the intestinal walls and develop to second stage, finally passing to the large intestine for final maturation. The prepatent period is 6 weeks.

Location: Caecum and large intestine, where the adult worms attach by threading their thin anterior ends through the mucosa.

Geographical Distribution: Trichuris is a common swine parasite throughout the world.

Significance: The swine whipworm causes economic losses by producing poor growth and reduced feed efficiency.

Effect on Host: Larvae burrowing into the intestinal walls can cause irritation. Most of the pathology is from adult worms in the large intestine, which suck blood and damage the mucosa. This produces anaemia, bloody and watery diarrhoea, and occasional deaths. Infections in young pigs cause loss of appetite and slow stunted growth.

Diagnostic Information: Characteristic eggs in faeces; worms at postmortem examinations.

Control: General control practices as discussed in the Overview are applicable. Eradication is difficult, because eggs may be infective for 6 years on soil.

Trichuris– adults		Typical Bi – polar egg
Adult T.suis attached to intestinal wall		Scanning electron microscope photograph Trichuris embedded in intestinal wall