Evaluation of a gel-immunization technique used with two different Immucox vaccine formulations in battery and floor-pen trials with broiler chickens.
The use of a gel-immunization technique with Immucox vaccination was compared and evaluated against other immunization methods in battery and floor-pen immunization trials. Gel immunization was found to be superior to immunization by gavage, by spray cabinet, or by the conventional delivery method of Immucox in a battery trial. Significantly enhanced protection as measured by weight gain, coupled with the establishment of a more uniform primary immunizing infection as evidenced by greater intestinal lesions and increased oocyst shedding, was seen in gel-immunized birds. In addition, cross-protective battery trials determined that the strain of Eimeria maxima found in the Immucox vaccine failed to elicit protection against a recent field isolate of E. maxima as measured by average weight gain and lesion scores. A reformulation of the Immucox vaccine that included the field isolate of E. maxima was required to elicit a protective immune response against challenge by the field strain. A floor-pen experiment demonstrated that gel immunization of 1-day-old roaster chickens resulted in performance parameters of average weight gain, average bird weight, and feed conversion that did not differ significantly from those recorded for medicated nonimmunized birds.
Danforth
H D
HD
Parasite Biology and Epidemiology Laboratory, USDA, ARS, LPSI, Beltsville, MD 20705, USA. hdanfort@gppl.arsusda.gov
Lee
E H
EH
Martin
A
A
Dekich
M
M
D000818:Animals; D002645:Chickens; D003048:Coccidiosis / Q000517:prevention & control / Q000662:veterinary*; D004539:Eimeria / Q000276:immunology*; D005069:Evaluation Studies as Topic; D005782:Gels; D008297:Male; D011201:Poultry Diseases / Q000517:prevention & control*; D016052:Protozoan Vaccines; D014611:Vaccination / Q000379:methods / Q000662:veterinary*; D015430:Weight Gain
D005782:Gels; D016052:Protozoan Vaccines