Evaluation of a commercially available hyperimmune plasma product for prevention of naturally acquired pneumonia caused by Rhodococcus equi in foals.
OBJECTIVE
To determine efficacy of a commercially available hyperimmune plasma product for prevention of naturally acquired pneumonia caused by Rhodococcus equi in foals.


METHODS
Randomized clinical trial.


METHODS
165 foals.


METHODS
Foals were randomly assigned to 1 of 2 groups (hyperimmune plasma or nontreated controls). Foals with failure of passive transfer (FPT) of immunity were treated with hyperimmune plasma and evaluated as a third group. Foals that received plasma were given 950 ml between 1 and 10 days of age and between 30 and 50 days of age. A tracheobronchial aspirate was obtained from foals with clinical signs of respiratory tract disease for bacteriologic culture.


RESULTS
A significant difference in incidence of pneumonia caused by R equi in foals with adequate passive transfer was not detected between foals that received plasma (19.1%) and nontreated foals (30%). Of 13 foals without FPT that received plasma and developed pneumonia caused by R equi, 12 developed disease prior to administration of the second dose of hyperimmune plasma. Incidence of undifferentiated pneumonia of all causes was not different between groups.


CONCLUSIONS
Intravenous administration of the commercially available hyperimmune plasma was safe, and the product contained high concentrations of anti-R equi antibodies. However, within this limited foal population, the difference in incidence of pneumonia caused by R equi observed between foals that received plasma and control foals was not significant.
Giguère
Steeve
S
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA.
Gaskin
Jack M
JM
Miller
Corey
C
Bowman
James L
JL
D000193:Actinomycetales Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D006734:Horse Diseases / Q000276:immunology / Q000517:prevention & control*; D006736:Horses; D007112:Immunity, Maternally-Acquired; D007116:Immunization, Passive / Q000662:veterinary*; D018410:Pneumonia, Bacterial / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D016929:Rhodococcus equi / Q000276:immunology* / Q000472:pathogenicity
D000907:Antibodies, Bacterial