M. Stankiewicz et al., DRUG-ABBREVIATED INFECTIONS AND DEVELOPMENT OF IMMUNITY AGAINST TRICHOSTRONGYLUS-COLUBRIFORMIS IN SHEEP, International journal for parasitology, 26(1), 1996, pp. 97-103
A protective immune response without liveweight loss can be induced in
sheep against T. colubriformis but results depend on the anthelmintic
used and duration of immunizing infections. More than 90% protection
was achieved in sheep immunized by three 15- or 7-day oxfendozole abbr
eviated infections or three 21-day nonabbreviated infections. Only 41%
protection was induced by 3-day oxfendozole abbreviated infections. S
ignificantly higher worm burden and faecal egg counts were present aft
er challenge in sheep immunized by 7-day levamizole abbreviated infect
ions compared to 7-day oxfendazole abbreviated infection. Liveweight g
ains of sheep immunized by 15- and 7-day abbreviated infections sere n
ot significantly different than non infected controls. Liveweight loss
seemed to be associated with high activity of mucus peroxidase and hi
gh numbers of eosinophils in the intestinal lumen. High parasite numbe
rs seemed to be associated with low activity of alkaline phosphatase i
n mucus. Mucus peroxidase, arylsulphatase, larval migration inhibition
of mucus, mucus or serum antibody against L(3) excretory/secretory an
tigen or somatic L(3), L(4) and adult antigen were not associated with
protection.