440 
REVIEW.—CATTLE PATHOLOGY. 
taken while the animal is hot; or muddy water, or that which is 
corrupted, or holds in suspension the remains of vegetables or of 
insects in a putrifying state—these act like corrupted and empoi¬ 
soned food. They irritate and inflame the gastro-intestinal mucous 
membrane. The absorption of chyle which they produce, and its 
passage in the circulatory current, determine an alteration of the 
blood, which is no longer misunderstood in our days—an altera¬ 
tion, the effects of which manifest themselves not only on the internal 
tunics of the heart and bloodvessels, but also on the nervous centres, 
whence tonic medicine, stimulants, purgatives administered at im¬ 
proper times, may change a simple gastric affection, a slight inflam¬ 
mation of the mucous meinbrano-stomach and intestines, into a gas- 
tro-enteritis serious, acute and mortal, by the super-excitation which 
they determine : for purgatives, if they do not produce alvine 
evacuation from the ox, are sure to excite inflammation of the in¬ 
testines. It is to the employment of the neutral salts and minor 
purgatives that we should have recourse when any thing indicates 
the propriety of purging. 
2. A cold and humid temperature, sudden suspension of the 
perspiration by means of a cold wind charged with moisture, or 
long continued rain or snow—these are so many causes of gastro¬ 
enteritis, especially if the animals are submitted to their influence 
while an active perspiratory process is going forward, and during 
either work or repose. The act of reposing on a humid soil after 
fatiguing exercise has the same result. The custom which agri¬ 
culturists have, of unharnessing their cattle in the open air on their 
return from labour, of leading them to the drinking troughs, and 
then turning them into the pasturages at whatever time of the 
evening it may be, and to whatever state of excitement and per¬ 
spiration the animals may have been driven, is likewise a frequent 
cause of gastro-enteritis. All these refrigerating causes act 
at once upon the skin, the capillary structure of which is then less 
easily traversed by the blood, which is necessarily repelled towards 
the centre. The cutaneous transpiration no longer existing, it re¬ 
sults that the organs in sympathetic relation with the skin, such as 
the mucous and the serous membranes, should supply this function, 
and thence results gastritis, bronchitis, pleurisy, pneumonia, ac¬ 
cording to the predisposition of the individual: for, the interior 
membranes, overwhelmed by the sudden collection of these fluids, 
and irritated by the congestion which they occasion, become in¬ 
flamed with so much the greater intensity as the subject possesses 
the power of vital re-action ; and if this fluxion continues, it neces¬ 
sarily determines a state of lever, more or less intense, in propor¬ 
tion to the individual vitality of the patient. Sudden variations 
of the atmosphere, from hot to cold and from dry to humid cold, 
produce the same effects; while a warm and humid temperature 
