The use of immunofluorescence techniques for the laboratory diagnosis of transmissible gastroenteritis of swine.

Over a four year period, 74 of 250 field outbreaks of enteric disease (30%) and 110 of 440 swine (25%) were positive for transmissible gastroenteritis by immunofluorescence procedures. Of 141 swine from herds positive for transmissible gastroenteritis 110 (78%) were positive by fluorescent antibody techniques. The fastest, easiest to perform and most effective procedure was the examination of frozen sections of the jejunum from acutely ill animals by the fluorescent antibody tissue section technique. Only two herds were found to be positive by the fluorescent antibody tissue culture technique which were negative by fluorescent antibody tissue section technique. A considerable number of outbreaks, 21 of 74 (28%), of transmissible gastroenteritis were detected by immunofluorescence in swine over two weeks of age. The majority of outbreaks of transmissible gastroenteritis, 50 of 74 (68%), occurred in Missouri during the months of January through April and 63 of 74 (85%) during the months of December through May. The recurrence of the disease in a number of counties over a four-year period suggest the possibility of endemic foci.