Cooperia (small intestinal worm) in cattle

Cooperia is the most common worm isolated from cattle dung samples across northern Australia. One reason why it is so commonly found is that it has very high egg-laying potential, with fecundity (daily egg-laying capacity) estimated at up to 2,700 eggs per day, depending largely on the infection dose, with less eggs laid/female/d when higher doses of larvae are ingested.

Another feature of Cooperia infection is rapid completion of the life cycle within the host cattle, with eggs being laid as soon as 14-16 days after infection.