1866. | The Cattle Plague. 27 
“1. Period of Ineubation.—This is the latent period of the dis- 
ease, beginning with the reception of the poison by the animal, and 
terminating when the symptoms of its development in the system 
become apparent. The duration of this period has been variously 
stated, but all my observations lead me to conclude that it terminates 
on the seventh day, by the outward manifestation of distinctly re- 
_ cognizable indications. These are— 
“2. The Earliest Recognizable Symptoms.—They are enumerated 
as nearly as possible in the order in which they appear. 1. Loss of 
appetite. This shows itself (1) by an aversion to all sorts of ‘ green’ 
food. The next day or the following there is (2) indifference to 
food of any kind. The animal still eats, but languidly, does not 
lick out the pail, or leaves a portion of the meal, and soon thereafter 
refuses food altogether. She now ceases to chew the cud, and from 
this time there is commencing constipation, with progressive dimi- 
nution of the milk. She looks depressed, stands much in the same 
posture, with drooping head and reclining ears. The ears, horns, 
and other extremities are now sensibly under their natural tempera- 
ture. The breathing is yet but slightly accelerated, and the expira- 
tion (or outbreath) perceptibly prolonged, and the pulse rises a few 
beats in frequency. It 1s at this period the orifice of the vagina 
reddens, and the colour deepens as the disease advances. This ap- 
pearance of the vulva is the most characteristic and trustworthy 
mark of the disease at this stage. A faint red or purple line about 
the same time appears on the undergum along the roots of the 
teeth. All these symptoms concur within a day or two of the in- 
cubation period. The diseased condition of the internal organs 
after death clearly pots to this and the preceding period of the 
disease as the proper time for successful treatment, before destructive 
changes have too far advanced. 
“3. More advanced Symptoms.—The breathing is now more 
accelerated, oppressed, sighing, and laborious. The number of 
respirations varies generally from 36 to 70 per minute. The pulse is 
more rapid (from 60 to 110 pulsations per minute) and weaker. 
There is continued loss of appetite, constipation, and thirst. The 
superficial membrane of the mouth, especially of the inner side of 
the upper lip, roughens, and a viscid discharge appears in the vagina. 
A similar appearance is seen on the membrane of the vagina where 
it joms the skin. The milk is scanty, and entirely changed to 
cream, or there is none at all. All the other symptoms are more 
decidedly pronounced. The likelihood of recovery is greatly dimi- 
nished by delaying treatment to this period. 
“4. Most advanced Symptoms.—They are those which shortly 
precede death, and are unattended by any very marked outward 
signs of pain. ‘The breathing is now slow, very laborious, and 
moaning or grunting. Pulse slow and small. Where purgatives 
