Proliferative responses of lymphocytes in Bovicola ovis-infested lambs.

Proliferative responses of peripheral blood and prescapular lymph node lymphocytes from 8 B. ovis-infested and 8 naive lambs to concanavalin A (Con A) and soluble antigen of B. ovis were examined in vitro. The numbers of lice and the extent of cockle were also assessed on each lamb. Prescapular lymph node lymphocytes from infested lambs showed significantly higher responses to B. ovis antigen than those from naive lambs. Only a marginal difference was observed between infested and naive lambs in the response of lymphocytes from peripheral blood. Proliferative responses to Con A by prescapular lymph node or blood cells were not significantly different between groups. The results indicated a relationship between the intensity of louse infestation and the proliferative response of prescapular lymph node lymphocytes to B. ovis antigen.