54 Veterinary Elements. 



movement of the long muscle fibres, together with, the con- 

 traction of the short circular muscle fibres, the waste ma- 

 terial is passed back and is given a more or less ball -like 

 form. It is in the floating colon particularly that the feces 

 (dung or waste material) take their form. The next 

 portion of the canal is the straight gut (or rectum), an 

 organ with thick dilatable walls; it lies above the blad- 

 der in the male, in the female above the vagina and 

 uterus. Its location will thus account for the passage of 

 feces via the vagina and vulva, a serious condition, usu- 

 ally the result of accident during copulation (mating) or 

 parturition (the act of bringing forth the young). The 

 point of exit of the feces is known as the anus, which is 

 made up principally of circular muscular fibres, the action 

 of which is to close the opening and thus prevent the 

 involuntary passage of feces. In certain forms of paraly- 

 sis the anus is not under control, consequently the feces 

 pass away at all times. The process of emptying the 

 rectum is known as defecation and is performed by con- 

 traction of the abdominal muscles and relaxation of the 

 muscular fibres of the anus. The anus tends to recede 

 and become less tense with age. Horsemen speak of a 

 horse being "well buttoned up," a desirable condition, 

 evidencing good nervous and musculartone, the expression 

 refers to the condition of the anus. When making the 

 examination the tail (dock) is lifted, a flabby tail is very 

 undesirable, but a strong dock, as it is termed, is another 

 indication of tone, showing that the muscles of the tail 

 have strong contractile power; allowances will have to be 

 made for horses that have had their tails "nicked," an 

 operation in which the muscles that pull the tail down 

 have been cut. 



