304 



DISEASES OF THE LIVER. 



only become common towards the end of the winter. During the second 

 or middle period (December and January) the patients lose flesh, appear 

 less active, show less regular appetite and greater thirst. The conjunctiva 

 becomes pale and swollen, the sclerotic has a bluish tint, and the eyelids 

 are somewhat infiltrated. The wool appears drier and less curly ; locks 

 of wool part readily from the skin, and the individual fibres become dry 

 and fragile. 



This phase is accompanied by very marked anaemia, rapid exhaustion 

 during movement, and inability to run for any length 

 of time. 



The different methods of examination reveal 

 nothing specially striking, except that the valvular 

 sounds of the heart are sharper, and that trifling 

 oedema occurs under the thorax and abdomen. 



Microscopic examination of the faeces reveals the 

 presence of eggs of distomata. The sheep rapidly 

 become thin from about the end of January, even 

 although the appetite persists and nourishing food 

 is given. 



III. Third, or wasting, period. The decline, 

 which sets in about February, appears extremely ob- 

 stinate, and resists all treatment. 



The patients become feeble, eat less, and digest 

 badly. Submaxillary oedema, common to advanced 

 wasting diseases, then appears. If the sheep are re- . 

 maved from the fold to pasture, the swelling of the 

 submaxillary space is very noticeable. It consists in 

 an indolent oedematous tumefaction, which disappears 

 when the animals are travelled, but reappears when 

 grazing on account of the low position in which the 

 head is then held. 



The condition then becomes complicated with 

 diarrhoea, and soon grows alarming. On examination, extensive dropsy 

 may often be found in the thorax, pericardium, and abdomen. 



Death results from exhaustion ; the animals do not appear to suffer, 

 but become extraordinarily anaemic, and perish without a struggle. The 

 blood is simply rosy in colour, like gooseberry syrup : the clot is soft 

 and gelatinous : the number of red blood corpuscles has fallen from 

 about seven millions to a few hundred thousand. 



Icterus is rare, though certain cases have been described where it has 

 appeared during the last and even during the middle stage. • 



When animals begin to die in a district which has long been infested, 

 the losses are enormous, the condition sometimes constitutes a jjerfect 



Fig. 160.— The large 

 American fluke 

 (Fasciola magna), 

 natural size. 

 (Stiles, Annual 

 Eeport, U.S.A. 

 Bureau of Agricul- 

 ture, 1901.) 



