_Causes._ This comes usually from troubles of innervation. Paraplegia,
dorsal and lumbar fractures with injury to the spinal cord, brain
lesions, hæmoglobinuria with effusion pressing on the cystic plexus,
overdistension of the viscus, from cervical spasm, urethral stricture or
calculus or parasite (strongylus gigas), acute or chronic cystitis. In
dogs it may come from obstruction by enlarged prostate. Polypus blocking
the cervix and chronic disease of the walls of the organ are additional
causes.
_Symptoms._ More or less complete retention of the urine. The bladder
cannot be completely emptied except by powerful contractions of the
abdominal muscles. Habitually it may escape in drops, or in jets at
intervals during exercise. Palpation will show overdistended bladder as
a tense, elastic mass. But as overdistension may occur without
paralysis, no case can be certainly diagnosed without catheterization to
show that the urethra is free.
When the paralysis affects the cervix, the urine escapes continually and
trickles down the insides of the hips in mares, or from the sheath in
males.
_Diagnosis_ demands catheterism and rectal examination.
Complication. Cystitis by retention. Infection by catheter.
_Treatment._ Corresponds to causes. These corrected, use aseptic
catheter often. After extreme distension empty partially, or inject a
few ounces of borax or boric acid solution. Thus avoid collapse and
inflammation, and secure antisepsis. Give tone by a course of strychnia,
(ergot, belladonna), mustard blister; turpentine in small doses. Better
electricity, 1 pole in bladder, 1 on pubic symphysis. Apply for 5
minutes.