ON SPASM OF TH K DIAPHRAGM. 
25 
in a few others it was natural and regular. In most it was from 
40 to 60 in a minute. After several of them had been bled, both 
the pulse and the spasm increased in frequency, but subsided, 
generally, shortly afterwards ; and repeatedly I have observed 
that whatever increased the pulse, increased in the same ratio 
the spasm, thus shewing the great connexion between the cir- 
culatory system and the spasm of the diaphragm. 
Length of Time the Spasm existed . — Out of sixteen cases, one 
lasted only for a few minutes ; two, from seven to eight hours ; 
two, about fifteen hours ; two, eighteen hours ; four, two days ; 
four, from two to three days ; and one, four days. 
In what Breed . — It appears that most of the horses that have 
been subject to spasm have been either thorough or half-bred ; 
and I am not aware that there is a single case on record in 
English works of a cart-horse being so. One case, from a fo- 
reign Journal, is mentioned as being “ a draught-horse but 
as he was drawing a cabriolet, I do not think he was what we 
mean by a cart-horse. Four or five have been small ponies. 
Age . — From a yearling up to twenty years of age ; but in some 
their ages have not been stated. 
Cause . — As naturally would be supposed, many of these cases 
are brought on whilst hunting, running in coaches, or any thing 
that causes great exertion or increased respiration : but it is also 
very certain that quite as many are caused by or dependent 
upon some irritation either in the stomach or intestines, or both : 
but, what is a little curious, the spasm does not generally come 
on while the horse manifests the greatest pain by pawing or roll- 
ing about, but usually when these active symptoms are on the 
decline, as if some metastasis takes place from those parts to the 
diaphragm, though I am inclined to believe that there is still 
some irritation going on there, but not of so painful a nature. 
Several of these cases have originated (but before the spasm com- 
menced) from gastritis, in consequence of the animal having eaten 
a quantity of oats ; others have been found ill in the fields with 
spasm of the bowels, or with gastro-enteritis, and have continued 
ill for a length of time before exciting the spasm. Some cases of 
spasm of the diaphragm originate without any apparent cause ; but 
I am inclined to think it is generally brought on from some sym- 
pathy existing between the stomach and intestines, as was clearly 
so in the case I have mentioned, while the horse was standing 
still in the stable, but labouring under the effects of a strong dose 
of croton seeds. It has also existed whilst a horse had an ulcer- 
ated jejunum, supposed to have been caused by worms. It has 
likewise been observed in a solitary case of introsusception of the 
intestines. 
VOL. XVI. 
D 
