CONTAGIOUS DISEASES OF ANIMALS. 
71 
Second. Their owners are usually responsible and honorable 
men who would be little likely to sell at the current high market 
rate animals that they know to be infected. 
Third. Thoroughbreds are always sold with pedigree, and 
the buyer is fully acquainted witli the position and standing of 
the seller, so that in the case of infected animals the breeder 
would have been constantly subject to an action for damages. 
Fourth. Until recently thoroughbred cattle were compara¬ 
tively seldom sent west to our unfenced pasturages, so that if 
some did carry infection into new herds, the latter were still on 
well fenced farms, and were kept rigidly apart from other stock 
to secure the purity of the breed; and thus the infection had a 
good chance to attack all the herd and to die out for lack of 
fresh susceptible subjects. 
Such an immunity of a country in close proximity to an in¬ 
fected one is not at all unprecedented. Europe furnishes an 
exact parallel. For centuries the lung plague has prevailed in 
Central Europe, where it is kept up by the active cattle traffic and 
the constant importations from the infected east. But Spain 
and Portugal on the south, and Scandinavia on the north, being 
out of the line of direct traffic, keep clear to the present day—the 
few invasions of the northern nations having been easily repelled 
by prompt isolation and slaughter, while the less enterprising 
southern peninsula has not even once been called upon to sup¬ 
press an outbreak. 
Dangers Increasing. 
Bnt our dangers to-day are far greater than they have been in 
the past. Tens and hundreds of thoroughbred cattle are being 
constantly shipped to the west, and the great demand is now for 
the unfenced ranges on the plains and beyond them. There, the 
disease once introduced, would find all those favorable conditions 
which have perpetuated it for centuries on the steppes of eastern 
Europe and Asia, in spite of the best efforts of science, aided by 
the ungrudging support of the governments. These conditions are 
identical with those of Australia, where the disease has defied 
every effort to extirpate it, though these were carried out almost 
