268 Atony of the Fore-sttmiaclis. 



Anatomical Changes. Eumen and omasum occasionally 

 also the reticulmn, are more or less dilated. The increase in size 

 of the omasum is particularly obvious, although in young calves, 

 the rumen is most enormously dilated (Imminger). The con- 

 tents of the omasum are unusually dry, almost rocklike, but 

 they can be ground up into a fine powder between the fingers; 

 they completely fill the omasum {"Ldserverstopfung" [Ger- 

 man]). The rumen likewise usually contains desiccated, fetid 

 masses of feed and usually also gases. If the affection has been 

 caused by feeding thin mashed, or boiled potatoes, the contents 

 of the rumen look like street mud or like a thin dough (8ipp, 

 Eberhardt), while the omasum may not be obstructed, as is 

 occasionally the case in other cases of atony. 



Desiccation of the feed-iiiash in the omasum without dilatation of the organ 

 is a common but negligible finding in severe febrile general diseases or other affec- 

 tions in which the movements of the fore-stomachs have been diminished for a con- 

 siderable time. 



The mucosa of the fore-stomachs either does not show any 

 changes at all, or it appears reddened uniformly or in spots, oc- 

 casionally with hemorrhagic spots, if the process has lasted for 

 some time. These changes can easily be seen postmortem, since 

 the cornified squamous epithelia soon after death become de- 

 tached in shreds or adhere to the masses of feed (common post- 

 mortem appearance!). One occasionally finds pressure-necrosis 

 or hemorrhagic ulcers in the omasum, usually combined with a 

 general acute peritonitis. The latter, however, may be present 

 without pressure-necrosis of the wall of the omasum. 



In secondary atony the causative underlying disease can 

 generally be ascertained on postmortem examination. 



Symptoms. In the acute form of the disease one only no- 

 tices a diminution of the appetite and thirst ; rumination is in- 

 frequent and sluggish and there is a decrease in the energy of 

 the rumen movements which are, however, normal in frequency 

 (simple indigestion [Eber]). If these s^miptoms, which are not 

 very prominent, are overlooked, and if the animals are not prop- 

 erly treated, the clinical picture of the chronic form gradually 

 develops. 



The chronic form usually develops very gradually, although 

 it may occasionally evolve within a very few days into a charac- 

 teristic, clinical picture. The animals from time to time take 

 less feed and they generally prefer rough feed ; in some cases the 

 appetite may be perfectly normal for several hours and even 

 for a few days. Thirst is generally diminished, but it may also 

 be increased (Bouley, Heu). Here and there the animals lick 

 greedily. Eumination is, as a rule, gradually diminished and it 

 may also occasionally l)ecome suppressed suddenly. As a rule 

 rumination only occurs from time to time; after a longer inter- 



