A potential krimpsiekte vaccine.
Krimpsiekte, a chronic form of cardiac glycoside poisoning, is an important plant-induced intoxication of small stock in South Africa. It is caused by cumulative, neurotoxic bufadienolides, such as cotyledoside. A cotyledoside-bovine serum albumin conjugate was synthesized to immunize animals. The efficacy of the cotyledoside-conjugate in inducing an immunological response was ascertained in rabbits (n = 4) and sheep (n = 4) by determining cotyledoside antibody titres with an ELISA using cotyledoside-hen ovalbumin as antigen. The formation of anticotyledoside antibodies was induced in both rabbits and sheep following immunization with the cotyledoside-protein conjugate. Protection provided by the vaccine was demonstrated by challenging sheep (n = 4) with repeated, daily doses of cotyledoside (0.015 mg/kg) administered intravenously, commencing 45 days after the initial vaccination. One control animal died on Day 3 of the challenge period and the other was severely affected after administration of the third cotyledoside dose. The immunized ewes (n = 2) remained clinically unaffected and the challenge was suspended following six daily injections. Vaccination as a means of preventing krimpsiekte seems to be quite feasible and deserves further investigation.
Botha
C J
CJ
Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110 South Africa. christo.botha@up.ac.za
Crafford
J E
JE
Butler
V P
VP
Stojanovic
M N
MN
Labuschagne
L
L
D000818:Animals; D000906:Antibodies / Q000097:blood; D000917:Antibody Formation; D002018:Bufanolides / Q000008:administration & dosage / Q000276:immunology*; D002301:Cardiac Glycosides / Q000506:poisoning*; D004305:Dose-Response Relationship, Drug; D004306:Dose-Response Relationship, Immunologic; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary; D005260:Female; D008297:Male; D009206:Myocardium / Q000473:pathology; D010939:Plant Poisoning / Q000517:prevention & control / Q000662:veterinary*; D010947:Plants, Toxic; D011817:Rabbits; D011897:Random Allocation; D012756:Sheep; D012757:Sheep Diseases / Q000517:prevention & control*; D014611:Vaccination / Q000379:methods / Q000662:veterinary*
D000906:Antibodies; D002018:Bufanolides; D002301:Cardiac Glycosides; C038322:cotyledoside