Infection-induced protection against Haemonchus contortus in merino and manchego sheep. Relationship to serum antibody response.
Resistance to primary and secondary infections with Haemonchus contortus was studied in 10-month-old Manchego and Merino sheep. No notable interbreed differences were observed after primary infections in the parameters determined (prepatency period, faecal egg output, abomasal worm burden). Previously infected sheep (200 L-3/kg live weight (lw)) from both breeds showed notable protection after challenge (400 L-3/kg lw), evidenced by lower eggs/g faeces (epg) values and worm burdens. A protective response in the Manchego breed was associated with arrested development of fourth stage larvae in the abomasal mucosa, whereas in the Merino breed a more rapid expulsion mechanism seems to be involved. Serum antibody levels (IgG, IgA) were infective dose-dependent and protection from re-infection was not clearly related to the parasite-specific IgG response estimated by enzyme-linked immunosorbent assay (ELISA) and Western blotting.
Gómez-Muñoz
M T
MT
Departamento de Patología Animal I, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain. mtgomez@eucmax.sim.ucm.es
Cuquerella
M
M
de la Fuente
C
C
Gómez-Iglesias
L A
LA
Alunda
J M
JM
D000018:Abomasum / Q000469:parasitology; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D005243:Feces / Q000469:parasitology; D005260:Female; D006188:Haemonchiasis / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D006189:Haemonchus / Q000302:isolation & purification; D008297:Male; D010270:Parasite Egg Count; D012756:Sheep; D012757:Sheep Diseases / Q000276:immunology* / Q000517:prevention & control; D013045:Species Specificity
D000909:Antibodies, Helminth