588 THE COMPLETE GRAZIER. BOOK vi. 



- fluke pass from the sheep on to the grass, and the embryo then emerges 

 from the egg, and takes up its abode in the soft body of the small water- 

 snail, Limnseus truncatulus, the elegant, spiral, pale buif shell of 

 which is only about a quarter of an inch long. Within the body of the 

 snail the parasite undergoes further changes, and eventually the sheep, 

 feeding on moist herbage, takes in either the small infested snail, or 

 possibly some of the parasites that have deserted the snail for the 

 herbage. The flukes make their way from the stomach to the liver of 

 the sheep, and the cycle is repeated. 



Symptoms. From four to thirteen weeks may elapse after ingestion 

 of the parasites before functional disturbance becomes apparent. 

 Between November and January, however, the sheep becomes less 

 livery ; the mucous membrane about the eyes, the nose, and the gums 

 turns pallid ; and the animal shows a tendency to grow fat. At the 

 beginning of the year the sheep commences to get lean, becomes listless 

 and dejected, and other disorders, such as diarrhoea, are the precursors 

 of death. Aqueous cachexia, rot, rot dropsy, sheep-rot, liver disease, 

 liver fluke, jaundice, yellows, and verminous phthisis of the liver, are 

 other names for liver rot, and are all expressive of one stage or another 

 of this disastrous malady. 



Treatment. This involves liberal feeding, a free use of salt, and a 

 change of pasture from damp, low-lying lands, to those that are high 

 and dry. Sheep should not be allowed to graze water-meadows or 

 damp pasture in the autumn, but only in the spring when, after the 

 frosts of winter, they may reasonably be expected to be free from the 

 parasites. When there is no alternative to the grazing of wet land it 

 has been recommended that one portion should be used for sheep to 

 the end of May, and another portion for the exclusive autumn feeding 

 of sheep, horses alone having grazed the land in spring and summer. 

 When the sheep are transferred from the spring feeding grounds to the 

 autumn grounds, horses replace them on the spring lands. Dressings 

 of lime or salt, or of both, spread over the grass lands at the proper 

 season, will have the eifect of destroying the embryo flukes and the 

 snails which harbour them. Sheep should not be allowed to graze 

 infected lands too closely. 



RETENTION OF URINE. An inability to empty the bladder, whereby 

 the urine is caused to accumulate and distend the organ abnormally, is 

 not infrequently observed in sheep. It is mostly seen in males, and 

 particularly rams, while being got up for exhibition purposes, under 

 the influence of rich highly stimulating food. 



The chief cause of this defect as seen in sheep is due to the presence 

 of minute sandy particles, which block up the urinary passage at the 

 extreme end of the penis (worm). This gravelly matter is deposited 

 from the urine while in the bladder, and then passing along the canal 

 becomes arrested in the small worm-like appendix of the organ, thus 

 shutting in the urine and preventing its escape. The deposition of 

 sandy matter in the bladder is said by practical flock-masters to arise 

 from the excessive use of mangel and other food rich in sugar. We 



