Urinary System

The major manifestations of U.T. disease are - Abnormalities of the urine composition. - Abnormalities of the daily urine flow. - Pain and dysuria. - Uremia (principal manifestation in renal failure). - Rupture of the U.B., renal pelvis and urethra. - Defect in nervous control of the urination. - Urachal leakage of urine.

Food Animal Urology P.E. & evaluation of the urinary system Urolithiasis Bacterial diseases Toxic plants Parasitic diseases Miscellaneous conditions Congenital conditions Neoplasia

Physical examination External structures Urethral area in males Vaginal exam Cystoscopy Radiography Micturition – normal behavior Urine collection Normal frequency / quantity Palpation Urine characteristics Kidney function evaluation Kidney biopsy

Normal frequency / quantity Varies with water consumption, season, milk production, age and use Species ml/kg/day # times/day Sheep/goat 10-40 1-3/day Cattle 17-45 5-6/day

Palpation Rectal palpation of ureters in cattle Normally the size of straws Palpation of urinary bladder Rectally in cattle Abdominal palpation in small ruminants/calves Palpation of urethra Rectally or in perineal area

Urine characteristics Viscosity Normally watery Color Straw to amber colored normal Light yellow vs. dark No hemoglobin, myoglobin, blood Transparency Clear, transparent Turbid or cloudy abnormal Odor Ketones, strong ammonia abnormal Urinalysis

Red Urine Hematuria Hemoglobinuria Myoglobinuria Pyelonephritis, cystitis, urolithiasis, enzootic hematuria, embolic nephritis Hemoglobinuria Leptospirosis, bacillary hemoglobinuria, copper toxicity, post-parturient hemoglobinuria, cold water intoxication Myoglobinuria Cassia toxicity, capture myopathy * Anaplasmosis = normal urine

Kidney function BUN – 10-30 mg/dl Creatinine - < 2 mg/dl Creatinine may increase more quickly than BUN due to the ruminant’s ability to recycle urea through the rumen

Urolithiasis in Ruminants Uroliths in cattle, sheep, and goats are common. Although uroliths can be found anywhere within the urinary tract, urethroliths are responsible for most clinical problems.

Predisposing factors increased urine concentration urine stasis increased urine pH increased mineral excretion decreased urinary colloids desquamated epithelial cells UT infections increased urinary mucoproteins

Calculus composition phosphate calculi * silicate oxalate magnesium ammonium phosphate = struvite calcium phosphate = apatite silicate oxalate calcium carbonate

Phosphate calculi

Etiology and Pathogenesis Ruminant urolithiasis is considered primarily a nutritional disease. The prevalence of urolithiasis in the USA is highest in calves, lambs, and kids castrated at an early age and fed high-grain diets with roughly a 1:1 calcium to phosphorus ratio or a diet high in magnesium. Ruminants fed high-grain diets with a low calcium to phosphorus ratio are at increased risk of developing struvite uroliths, while ruminants grazing on silica-rich soil are predisposed to form silica uroliths

Clinical Findings stranguria - (often mistaken for constipation) anorexia, mild bloat, lethargy treading, stretching, kicking @ abdomen vocalization (especially goats) palpable bladder distention abdominal palpation in small ruminants rectal palpation in large ruminants azotemia

Clinical Findings Clinical signs may be associated with partial or complete urethral occlusion. Animals with partial obstruction dribble blood-tinged urine after prolonged, painful (stranguria) attempts at urination; before complete occlusion occurs, urine may dry on the preputial hairs and leave detectable mineral deposits.

Clinical Findings… Obstruction induced by urethroliths causes urine retention and leads to bladder distention, abdominal pain, and eventual urethral perforation or bladder rupture, with death from uremia or septicemia Subcutaneous swelling containing urine due to urolithiasis and urethral perforation. By permission from Blowey RW, Weaver AD

Diagnosis Diagnosis based on the history, clinical signs, and physical examination is usually straightforward. Hypersensitivity in the region of the sigmoid flexure may be evident. Palpation may identify abnormal pulsations of the urethra and tissue swelling associated with the obstruction

Treatment and Control phenothiazine tranquilizers IV fluids - 0.9% NaCl slow drainage of uroperitoneum via trochar in cases of ruptured bladder paramedian skin incisions to drain urine in cases of ruptured urethra antibiotics urinary acidifiers

Treatment and Control cont. In many instances, surgical management of the obstruction is all that is necessary; however, severely uremic and depressed animals require rehydration and correction of acid-base and electrolyte abnormalities Cystotomy followed by dietary management is believed to be a more effective long term solution to urolithiasis in sheep and goats.

Contagious Bovine Pyelonephritis

Bovine cystitis is an inflammation of the urinary bladder of cattle that may ascend the ureters to cause infection of the kidneys (pyelonephritis). A similar condition is seen in sheep. The condition is sporadic and worldwide in distribution. It is most often seen after parturition

Etiology and Pathogenesis: The most common causative agents are the Corynebacterium renale group of bacteria, including C renale , C cystitidis , and C pilosum , as well as Escherichia coli .

Clinical Findings and Lesions: The first sign observed may be the passage of blood-stained urine in an otherwise normal cow. As the infection proceeds up the ureters, causing inflammation and subsequent involvement of the kidney, the animal exhibits discomfort manifest by frequent attempts to urinate, anorexia, a slight fever, loss of production, colic with restlessness, tail switching, polyuria, hematuria, or pyuria. Chronic pyelonephritis (right) and acute pyelonephritis (left) Courtesy of Dr. Sameeh M. Abutarbush

Diagnosis: This is based on clinical signs; hematuria; a history of recent parturition; palpation of the left kidney for enlargement, loss of lobulation, and pain; endoscopic vaginal inspection for detection of inflamed and enlarged ureters; microscopic examination of the urine for WBC and bacteria

Treatment The treatment of choice for pyelonephritis due to the C renale group is penicillin (22,000 IU/kg, IM, bid) or trimethoprim-sulfadoxine (16 mg combined/kg, IM, bid) for ≥ 3 wk