e urine shows
nothing abnormal during the course of the disease until near the fatal
termination, when it may be deeply stained with the coloring matter of the
blood. (Hemoglobinuria; see Pl. XLV, fig. 3.) Although this symptom is
occasionally observed in animals which recover, yet it may generally be
regarded as an indication of approaching death. The pulse and respiration
are usually much more rapid than during health.
Other symptoms in addition to those mentioned have been described by
observers, but they do not seem to be constant, and only those described
above are nearly always present. As the end approaches emaciation becomes
very marked, the blood is very thin and watery, and the closing of any
wound of the skin by clots is retarded. The animal manifests increasing
stupor and may lie down much of the time. Signs of delirium have been
observed in some cases. Death occurs most frequently in the night.
The duration of the disease is very variable. Death may ensue in from three
days to several weeks after the beginning of the fever. Those that recover
ultimately do so very slowly, owing to the great poverty of the blood in
red corpuscles. The flesh is regained but very gradually, and the animal
may be subjected to a second, though mild, attack later on in the autumn,
which pushes the full recovery onward to the beginning of winter.
In the mild type of the disease, which occurs in October and November,
symptoms of disease are well-nigh absent. There is little if any fever, and
if it were not for loss of flesh and more or less dullness the disease may
pass unnoticed, as it undoubtedly does in a majority of cases. If, however,
the blood corpuscles are counted from time to time a gradually diminishing
number will be found, and after several weeks only about one-fifth or
one-sixth of the normal number are present. It is indeed surprising how little
impression upon the animal this very impoverished condition of the blood
appears to make. It is probable, however, that if two animals kept under
the same conditions, one healthy and the other at the end of one of these
mild attacks, are weighed, the difference would be plainly shown.
_Pathological changes observable after death._--In the preceding pages some
of these have already been referred to in describing the nature of the
disease. It is very important at times to determine whether a certain
disease is Texas fever or some other disease, like anthrax, for example.
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