I.TFE-lllSTOKY 01- AFEICAX LIAER FLUKE. 12D 



feed. At post-moitein over 20 adult flukes were obtained from 

 its liver, which was enlarged, had much thickened bile ducts, 

 and showed maiked disinteo-ration of its capsule. Recent 

 haemorrhag'es into the connective tissue around the terminal 

 part of the rectum and lower part of tlie abdomen, together with 

 a haemorrhag'ic sac betweeu the deep and superficial muscles 

 of the thigh, were present, and these haemorrhages contained 

 one or more Hukes. 



Similar results were obtained with a guinea-pig. which 

 died 74 days after the infective feed. 



A young sheep, bred from and belo'iging to a stock known 

 to be free from liver fluke, was fed with green barley con- 

 taminated with encysted cercariae from Litnnaea natcdensis, 

 two such feeds being given. On the first occasion only a few 

 cysts were available; on the second, about 250 cysts were 

 administered. The animal died 143 days afler the first and 

 11!> days aftei' the second infective feed, and 22o adult flukes 

 were recoveied from it at autopsy. Sixty-four days after the 

 second infective feed the animal was noticed to be less active 

 and to lie about a good deal. This behaviour continued at 

 intervals until it died. For seven days prior to death most of 

 its food was refused, but it ate its mash and some green barley 

 on the day previous to death. At post-mortem the body 

 appeared well nourished. The liver showed marked perilie])a- 

 titis, was greenish in colour, with numerous blackish 

 haemorrliag'es. There was slight oedema. The bile ducts were 

 greatly thickened and fibrotic. The intestines were heavily 

 bile-stained, and contained some flukes in the canal, which also 

 showed many small haemorrhages. All the blood-vessels of 

 the mesentery were engorged. A small haemorrhage beneath 

 the skin near the anus contained one fluke. The organ most 

 affected was the liver, from which 189 flukes were recovered. 

 The bile ducts were blocked in some places with tangles of two 

 or three flukes. 



Similar experiments were performed, using rats and mice, 

 with similar results. The minimum time before adult, sexually 

 mature flukes have been obtained experimentally has been 

 (i4 days. 



The eggs of Fasciola (////aiificd do not hatch leadily under 

 experimental (conditions, and my experience has been that they 

 take from 11 to 54 days Isefore the miracidia emerge. Direct 

 infection of laboratory-hred Limnaea nofalensis with the mira- 

 ( idia of F. (/if/(tntir(i has been carried out, so that the complete 

 develt)i)niental cycle is now demonstrated. 



FdscioJa f/if/anfica is fairly widely distribaited in South 

 Africa. Tlius, following on my communication to the 

 Veterinary Research Division in 1919, the i]wv Actina- 

 Director. Mr. D. T. Mitchell, sent to a well-kiiown " fluke "" 

 district in the Transvaal, and it was found that sheep and oxen 

 there were parasitised with F. f/lfjanficd, not F. hepafica, as 

 had been thought. Similar finds wej-e made in Swaziland. 

 F. r/if/anfjca has since been reported from several Transvaal 

 localities, and I have found it fairl.\ commonly in the livers of 

 cattle condemned for fluke in th'^^ Joliannesburg abattoirs. 



