Morphology of inhibited larvae of the bovine lungworm Dictyocaulus viviparus

Some morphological features of inhibited fourth stage (L4) and fourth moult larvae (4M) of the bovine lungworm Dictyocaulus viviparus are described. I nhibition was induced by maintaining the third stage larvae (L3) for 6 week s at 4 degrees C. Inhibited fourth stage (L4) and fourth moult larvae (4M) were collected by perfusion of the lungs of experimentally infected calves after necropsy at 15 and 68 days post infection (d.p.i.), respectively. Inh ibited 4M, isolated at 68 d.p.i., were about ten times larger than inhibite d L4 isolated at 15 d.p.i.