1 Nov., 1901.] QUEENSLAND AGRICULTURAL JOURNAL. 503 
EXPERIMENTS IN VACCINATION AS A PREVENTIVE OF 
“TRISTEZA.” 
(Translated from the French by A. J. Born.) 
At the sessions of 12th and 26th July, 1900, of the Central Society of 
Veterinary Medicine at Paris, Mons. Nocard said :— 
The Society is not unaware that the study of the “Tristeza” was one of 
the principal objects of the campaign which Mons. Ligniéres has just carried 
out in Argentina. A pamphlet published at Buenos Ayres, illustrated by a 
large number of drawings or microscopic photographs, furnishes an excellent 
résumé of this study. 
Mons. Ligniéres has shown, that “Tristeza” is only an indication of bovine 
malaria, that universal disease which Smith and Kilborne were the first to 
describe so clearly under the name of “Texas fever,” and which has been since 
found, under various names, in all countries of the world—except, perhaps, in 
France and in Central Europe. 
The “ Tristeza,” like Texas fever, is caused by an endoglobular hematozoa, 
the Piroplasma bigeminum ; like that fever, it communicates itself from diseased 
to healthy animals by inoculation, and the agent of inoculation is represented 
by young ticks, the progeny of mother ticks which have gorged themselves with 
the blood of diseased animals; the consequent mortality is considerable ; it is 
very rare that adult beasts resist a first attack; but this first attack confers 
perfect immunity, enabling a beast to resist the most serious attacks of 
infection. 
The symptoms are identical: high fever, intense hemoglobinuria, the result 
of a probable corpuscular destruction; in from twenty-four to forty-eight 
hours the number of red corpuscules may fall from 8,000,000 to 500,000 per 
cubie millimetre. The blood collected during the course of the attack yields a 
serum which can only be compared to syrup of gooseberries, or, better still, to 
that of black currants. The same lesions are found on post-mortem examina- 
tion; the spleen is enlarged, soft and black ; the liver and kidneys are con- 
gested and softened ; the gall bladder is enormous, filled with a thick, clotted 
bile; the bladder is distended by a large quantity of red urine like coffee 
grounds. ; 5 
Mons. Ligniére’s memoire is replete with new facts concerning the etiology 
of the disease and the life history of the micro-organism. But what it omits to 
state—it has been published too soon—is that Mons. Ligniéres has succeeded 
in vaccinating against the ‘“‘'Tristeza”’; before he left Buenos Ayres he gave 
a grand public demonstration, in the course of which several vaccinated animals 
were able to sustain, without discomfort, the inoculation of a dose of virulent 
blood which either killed all the control animals or made them seriously indis- 
osed. 
P This experiment is considerably far-reaching; it is the first time that 
vaccination against a hematozoic disease has proved successful. Mons. 
‘Ligniéres is about to renew the experiment in my course at Alfort. Two 
Breton bulls are in process of immunisation; next Sunday they, together with 
a fresh bull of the same breed, will be inoculated with a fatal dose of virulent 
blood. 
Tn a few days the control will exhibit the gravest symptoms of the disease}; 
it will in all probability succumb; the two vaccinated ones will remain 
perfectly healthy. invite those of our colleagues who are interested in the 
matter to watch this experiment; but, seeing that it is impossible to say just 
when it will be completed, I would ask the president to be good enough to 
nominate from amongst the members who live at the College, or in its neigh- 
bourhood, a commission to be charged with the duty of watching the experiment 
and of reporting on it at the next session. 
The bulletin of the Society would thus promulgate the first fruits of the 
important discovery made by Mons. Ligniéres. 
