THE DIGESTIVE SYSTEM. 259 



will be necessary in this case than the introduction of the 

 probang. This distension c^ the rumen arises from some 

 accidental and temporary cause,, and there is rarely any 

 continued manufacture of gas within the stomach ; some 

 calves become blown from the trick they frequently have 

 of sucking each others pizzle or ear'' (Youatt) . 



In cases of choking, the probang must next be passed, 

 and every obstacle removed. The tube should be made 

 to penetrate into the rumen, and thus tend to remove 

 mechanically any food accumulated round the cardia. 

 Through it, or directly through the cannla, may be in- 

 troduced some agent which will stimulate the torpid 

 rumen and chemically condense the gases pent up in it ; 

 sometimes these will rush out with force through the 

 probang and the relieved organ regain its tone; more 

 often medicinal agents are required. Compounds of am- 

 monia are most valuable in these cases. Liquor Ammoniaa 

 or the Spiritus Aromaticus (of course largely diluted) form 

 with the carbonic anhydride the ammonium carbonate, 

 which is a useful stimulant. ^' Chloride of lime '' is 

 usually to hand, and acts on the carburetted and sul- 

 phuretted hydrogens which are present, forming hydro- 

 chloric acid. Any excess of the bleaching powder acts 

 as an arrester of putrefaction and fermentation. This 

 agent is available, therefore, either in the early or late 

 stages. The sulphites and hyposulphite of soda also serve 

 to condense the gases which are causing over-distension. 

 Some farmers practise throwing cold water over the ab- 

 domen of an animal which is " blown -" this, of course, 

 acts by causing reflex contraction of the rumen, which 

 might lead to rupture if the openings were occluded and 

 thus the escape of gas prevented. Cases have been 

 relieved by means of the stomach-pump, cold water being 

 thrown in through the probang; nature herself adopts 

 the method of relief by vomition in some cases. Almost 

 always eructations take place, but the amount of gas thus 

 removed does not equal in amount that which is con- 

 stantly being set free. The administration of stimu- 

 lants and removal of accumulated gas generally requires 



