SKIN HYPERSENSITIVITY TESTS IN BUFFALOS PARASITIZED WITH TOXOCARA-VITULORUM

Skin tests were done using larval extract and excretory-secretory (ES) antigens injected intradermally in the neck area of 30, 11- to 200-da y-old buffalo calves and nine 27- to 100-day postparturition buffalo c ows, The skin of the buffaloes infected with Toxocara vitulorum, mainl y calves, demonstrated a hypersensitive response to antigens, especial ly to the larval extract antigens. Skin hypersensitivity responses wer e characterized by the presence of dermal nodules with progressive ind uration and an increase of up to four times the size of the original a rea at 30 min (immediate type) and at 72 h (delayed type) after inject ion, Histological preparations of skin reactions at 72 h showed a typi cal mononuclear cell infiltration, with eosinophils and perivascular c uffing in most of the animals, Fecal examination of 75 animals showed that 65 (86.7%) buffalo calves (9-115 days old) were parasitized with T. vitulorum. The peak of egg output from these animals occurred when they were approximately 45 days old.