to the Rearing and Feediny of Cattle. 
255 
sumption in cattle. The combustion of food, by which animal 
heat is supported, takes place in the intestines, and not in the 
luntjs, as is usually supposed. The intestines are, therefore, very 
liable to inflammation (union with oxygen). When cattle are 
protected from cold, and therefore not under conditions to be 
affected in their lungs, the decay (union with oxygen) of the 
putrid exhalations is imparted to the intestines, and, according to 
its intensity, produces either diarrhoea or dysentery. Mr. Pusey 
informed me recently that he knew several cases in which 
diarrhoea had broken out amongst sheep shedded according to 
Mr. Childers's plan. I should ascribe it, in all these cases, to an 
imperfect ventilation of the sheds, or perhaps to decayed food. 
Consider the various causes of diarrhoea and dysentery, and you 
will agree with me as to the explanation. Low and marshy 
grounds, flooded fields, bad water, over-work, the neighbourhood 
of stagnant ponds, the continuation of sultry weather, — all are 
causes which contribute to produce dysentery in our cattle ; all 
are causes also either to impart a pre-existing state of decay 
(union with oxygen) to the intestines, or to introduce a more than 
usual supply of that gas to the system.* 
The first class of diseases now mentioned is not infectious, be- 
cause putrid exhalations do not form their necessary consequence. 
Dysentery in cattle is indeed contagious, but this arises only when 
much decay proceeds in the body, as indicated by the putrid 
smell of the excrements. 
The second series, such as rot, is, on the contrary, highly con- 
tagious. A rot, perfectly resembling that of sheep, occurs in the 
human race, when decayed sausages or other putrescent matter is 
consumed. The unhappy patient becomes rapidly emaciated, 
the fluids in his body disappear, he dries to a complete mummy, 
and finally dies. On a post-mortem examination it is found that 
his liver and abdominal viscera have participated in the decay. 
This is a true case of rot in man, arising from decay communi- 
cated by his food, and perfectly analogous to the rot in sheep. 
Both arise from the same cause — i. e. by the communication of a 
decay previously existing is some other body. Mr. Cleeve, in his 
excellent ' Essay on the Diseases of Sheep,'-)- states "that May and 
June are the months in which the contagion is generally found to 
exist ; and then exactly in proportion to the prevalence of heat 
after showery weather ;" or, in other words, exactly when decay 
of animal and vegetable matter is at its maximum. The rot in 
sheep produces decayed exhalations, which, if brought into con- 
* The unpleasant diseases called red-water and black-water also seem 
to proceed from similar causes ; and arise when the kidneys, instead of the 
intestines, become the seat of the attack of oxygen. 
t Journal, vol.i. p. 313. 
