90 
Tlie Rot ill Sheep. 
The little hard lump about the size of a " mustard-seed," holding' 
calcareous matter, mistaken for a true tubercle, is the product of 
the Filaria bronchialix. ICxamiiied in the early stages of its 
formation, and when it presents little more than an ecchymosed 
condition, or a pus-like deposit, a male parent-worm will be seen 
coiled upon itself in the isolated miliary body. Having served 
the chief purpose of its life, the entozoon is about to die and 
become entombed in calcareous matter, his own structure contri- 
buting to this end by being involved in the process of calcifica- 
tion. Similar changes we believe to take place with the female 
parent-worms, but these, from their greater size and number, 
produce depositions far exceeding those of the male entozoa. In 
the still larger and softer deposits, which give here and there to the 
lung a flesh-like appearance, myriads of ova and young filariae 
of both sexes will be found, which, by their local irritation, 
produce the changed lung-structure in which they dwell. These 
are the revelations of the microscope, and beautifully do they 
exemplify one form of entozoic disease to which sheep are remark- 
ably prone. 
Among the advocates of the opinion that rot depends on 
inflammation of the liver was the late Mr. Youatt. He spoke very 
decidedly on the point, and attributed all the lesions which are 
observed in the body to this one primai'y cause. This view of the 
pathology of the malady appears to have emanated from Dr. Har- 
rison, who affirms that " Rot always commences with inflammatory- 
symptoms, and generally Avith an exudation of coagulable lymph 
under the tunic of the liver. In five or six days after contracting 
the rot, the thin edge of the liver," he says, " becomes of a trans- 
parent white or bluish colour, and this spreads along the upper 
and lower sides, according to the severity of the complaint. In 
severe cases the Avhole peritoneum investing the liver is diseased, 
and then it commonly assumes an opaque colour, interspersed 
with dark red lines or patches." 
Similar views were held by Hurtrel D'Arboval and by Davy. 
The latter-named author, after describing several morbid states 
of the liver, which he enumerates as " enlargement, indura- 
tion, ■ gangrene, concretions, &c.," says, " Now, we are well 
assured that these appearances never occur Avithout the existence 
of previous inflammatory action. Inflammation of the liver is 
a state of disease which it is evident has taken place." 
It is not a little remarkable that not only surgeons, but also 
such eminent veterinary authorities as Youatt and Hurtrel D'Ar- 
boval, should have committed so great a mistake respecting a 
disease of such common occurrence. Every farmer knoAvs that 
sheep give little or no evidence of ill-health at the commence- 
ment of rot, and that, when they do sicken, the symptoms indi- 
