..26 
Hereditary Diseases of Sheep and Pigs. 
constipation. When a decided tendency to apoplexy shows 
itself, means should be taken to prevent the manufactuie of an 
undue amount of blood, by givino^ unstimulating and not over- 
nutritive food in moderate quantity. The constant activity of 
secretion and excretion should also be secured by free ventila- 
tion and cleanliness ; by affording the animal access to good 
pure w^ater, and if necessary by the occasional exhibition of 
laxatives. Such measures will be much safer and more effectual 
than the copious blood-lettings and purgings which are often 
recommended in such cases, and which, though thoy may prevent 
the disease for the time, frequently do more harm than good, 
since without due attention to diet they increase the disposition 
to the excessive manufacture of blood. 
Epilepsy or Jits, as it is often significantly termed, occasionally 
occurs among sheep. The animal attacked becomes suddenly 
stupid, gazes vacantly about him, and falls down struggling and 
senseless. His muscles are thrown into violent and general 
spasms, his eyes start from their sockets and are often distorted, 
his jaws are forcibly closed, his tongue is protruded, and his 
faeces and urine are passed involuntarily from the violent spas- 
modic action. His respiration is irregular and gasping, and his 
circulation usually much disturbed by venous congestions. The 
convulsions vary much in severity and duration, usually lasting 
only a few minutes, but recurring repeatedly at very short inter- 
vals. Epilepsy occurs most commonly in young sheep in good 
condition, but also occasionally in lambs about weaning time. 
It may attack any kind of sheep, but is especially frequent among 
those that are delicately bred and of a scrofulous constitution. 
It is sometimes very violent, and occurs frequently without prov- 
ing fatal ; but its prognosis depends entirely upon its nature and 
cause. Thus, when de])ending on any local irritation of the 
intestines, or, in other words, if it is merely sympathetic or 
eccentric, it is usually tolerably easy of cure, is not likely to 
return after its cause has been removed, and is not usually here- 
ditary ; but when it depends on some morbid condition of the 
brain or nervous system, and occurs in animals of a scrofulous 
disposition, it is almost incurable ; is apt to occur again and 
again, until death puts a period to its attacks, and is almost always 
hereditary. It is distinguished from apoplexy by the absence of 
coma, and from tetanus by the intermissions of the spasms, and 
by the fact that it usually attacks one side or one half of the body 
more seriously than the other. Tlie precise nature of the disease 
is not well known : the functions of the brain appear to be dis- 
turbed or altogether held in abeyance, and the rest of the nervous 
system — thus released from the regulating and controlling in- 
fluence of its central director — acts in an irregular, and often 
