“…A definite statement about the occurrence and distribution of this disease can be made only through sero-epidemiologic examination of a representative cross-section of the whole cattle population. This is proven also by numerous treatises from countries involved in similar problems, such as Australia, Canada, the USA, South Africa, and Colombia (BOULANGER et a]., 1966(BOULANGER et a]., , 1971KUTTLER et a]., 1969;LONG et al, 1974;MERRIMAN et al, 1962;PAULL et a]., 1980;POTGIETER, 1979;ROGERS, 1971;TODOROVIC et al, 1977;UTTERBACK et al, 1972;ZAUGG and KUTTLER, 1985).…”