92 DISEASES OF THE HORSE. 



cause of irritation in the digestive organs, and a careful dieting will 

 avoid continued irritation by acrid vegetable agents. The bladder 

 should be examined to see that there is no stone or other cause of irri- 

 tation, and the sheath and penis should be washed with soapsuds, any- 

 sebaceous matter removed from the bilocular cavity at the end of the 

 penis, and the whole lubricated with sweet oil. Irritable mares should 

 be induced to urinate before they are harnessed, and those that clutch 

 the lines under the tail may have the tail set high by cutting the cords 

 on its lower surface, or it may be prevented getting over the reins by 

 having a strap carried from its free end to the breeching. Those 

 proving troublesome when " in heat " may have 4-dram doses of bro- 

 mide of potassium, or they may be served by the male or castrated. 

 Sometimes irritability may be lessened by daily doses of belladonna 

 extract (1 dram) , or a better tone may be given to the parts by balsam 

 copaiba (1 dram). 



DISEASED GROWTHS IN THE BLADDER. 



These may be of various kinds, malignant or simple. In the horse 

 I have found villous growths from the mucous membrane especially 

 troublesome. They may be attached to the mucous membrane by a 

 narrow neck or by a broad base covering a great part of the organ. 



Symptoms. — The symptoms are frequent straining, passing of urine 

 and blood with occasionally gravel. An examination of the bladder 

 with the hand in the rectum will detect the new growth, which may 

 be distinguished from a hard resistant stone. In mares, in which the 

 finger can be inserted into the bladder, the recognition is still more 

 satisfactory. The polypi attached by narrow necks may be removed 

 by surgical operation, but for those with broad attachments treatment 

 is eminently unsatisfactory. 



DISCHARGE OF URINE BY THE NAVEL, OR PERSISTENT URACHUS. 



This occurs only in the newborn, and consists in the nonclosure of 

 the natural channel (urachus), through which the urine is discharged 

 into the outer water bag (allantois) in fetal life. At that early stage 

 of the animal existence the bladder resembles a long tube, which is 

 prolonged through the navel string and opens into the outermost of 

 the two water bags in which the fetus floats. In this way the urine 

 is prevented from entering the inner water bag (amnion), where it 

 would mingle with the liquids, bathing the skin of the fetus and cause 

 irritation. At birth this channel closes up, and the urine takes the 

 course normal to extra-uterine life. Imperfect closure is more fre- 

 quent in males than in females, because of the great length and small 

 caliber of the male urethra and its consequent tendency to obstruction. 

 In the female there may be a discharge of a few drops only at a tipie, 

 while in the male the urine will be expelled in strong jets coincidently 

 with the contractions of the bladder and walls of the abdomen. 



