Du Plessis, J.L.; South Africa. Dept. of Agricultural Technical Services; De Lange, M.; Reinecke, R.K.; De Kock, V.E.; Walker, Jane B.; Tustin, R.C.
(Pretoria : Government Printer, 1970)
Ammonium sulphate precipitated gamma-globulins obtained from sheep immune to Cowdria ruminantium (Cowdry, 1925) failed to protect susceptible sheep against artificial infection by this parasite, irrespective of whether the ...