1. Food Animal Urology
M. S. Gill, D.V.M., M.S.

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

3. 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

4. External structures Purulent exudate in vagina or prepuce
Presence of crystals
Hemorrhages
Neoplasia
Vulva
Penis

5. Urethral area in males Look for obvious enlargements Hematomas
Ruptured urethra – “water belly”

6. Vaginal exam
Use a vaginal speculum in cow, ewe, doe, sow/gilt to examine urethral orifice

7. Cystoscopy Fiber optic endoscope to examine inside of bladder Epidural
Empty urine
Inject 500cc of air

8. Radiography Most useful in small or young ruminants
IVP or contrast study

9. Micturition – normal behavior
Cows
usually urinate right after standing
Arched back, raised tail, straddled legs
May urinate when eating, walking or lying down
Bulls
Arched back, raised tail
May dribble urine or urinate with repeated short pulsations
*Abnormal posture may indicate problems

10. Urine collection Cows Bulls/steers Ewes
stimulate vulva or catheterize
Bulls/steers
Preputial massage
Catheterization too difficult
Ewes
Hold off nose
Lasix® may be used IV but lowers S.G. of sample

11. 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
Swine
5-30
2-3/day

12. Palpation Rectal palpation of kidneys
Left kidney – 3rd-5th lumbar vertebra, mobile, usually on right side, can palpate rectally
Right kidney – 12th thoracic – 3rd lumbar vertebra, right side, not mobile, not palpable per rectum
Lobulated in bovine, smooth in sheep, goats, pigs
Feel for obvious enlargement, change in consistency, loss of lobulation, decrease in size of kidneys

13. 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

14. 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

15. Urine characteristics
Urinalysis
Specific gravity – – 1.040, as low as in dairy cows, water deprivation test used to access concentrating ability
pH – , aciduria with ketosis, lactic acidosis, paradoxical
Protein
Ketones
Glucose (stress, IV glucose, steroids, xylazine, *enterotoxemia*)
Blood, hemoglobin, myoglobin
Bacteria
Crystals

16. 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

17. 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

18. Kidney biopsy
Can be very helpful for diagnosis after other diagnostic tests have been exhausted

19. Obstructive Urolithiasis in Food Animals

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

21. Factors favoring development of obstruction
long, convoluted urethra - sigmoid flexures
urethral process in small ruminants
early castration
exogenous estrogens - growth promoting implants

22. Anatomy Common sites for obstruction: urethral process
vermiform appendage
“pizzle”
distal sigmoid flexure

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

24. Phosphate calculi

25. Calcium carbonate calculi

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

27. Clinical findings con’t.
blood or crystals on preputial hairs

28. Sequelae to untreated obstruction
ruptured urethra with accumulation of SQ urine ventrally
ruptured bladder with development of uroperitoneum

29. Sequelae to untreated obstruction
subcutaneous urine accumulation leads to necrosis and skin slough if not drained
uroperitoneum may not cause much damage to peritoneal cavity

30. Medical Treatment 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

31. Surgical Management
amputation of the urethral process (small ruminants)
urethral catheterization / retrograde flushing
perineal urethrostomy
tube cystotomy
ischial urethrostomy
cystostomy

32. Amputation of the urethral process
most common location for calculi to lodge (small ruminants)
exteriorize penis with animal sitting on rump - tranquilization &/or epidural may help
amputate process close to attachment to glans

33. Amputation of the urethral process
if calculi lodged in process
recurrence likely
use medical therapy concurrently

34. Urethral process amputation
in 14/16 cases (88%) which had urethral process amputation, obstruction was either not relieved or was relieved and recurred within 36 hrs.
10/14 goats (71%) successfully treated with urethral process amputation re-obstructed within a year (6 of these 10 re-obstructed within 3 days of surgery)

35. Urethral catheterization / retrograde flushing
difficult to catheterize bladder due to presence of suburethral diverticulum
catheterization may result in urethritis, urethral rupture, urethral stricture

36. Perineal urethrostomy
salvage procedure
low approach preferred to prevent urine scald
post-op stricture formation common

37. Perineal urethrostomy
urethral obstruction recurrence rate of 45% within 8 months of surgery and a 1-year survival rate of 17% reported
7 of 9 small ruminants (78%) developed stricture of within 8 months of surgery

38. Cystotomy
7 of 8 cases (88%) in which cystotomy was performed for urethral obstruction were healthy at the time of follow-up
cystotomy allows for removal of multiple calculi in the bladder as well as bidirectional flushing of the urethra
cystotomy had a long term survival of 88% as compared to a 55% survival with perineal urethrostomy

39. Tube cystostomy Useful in small ruminants and calves
Allows removal of calculi from bladder and ante- and retrograde flushing of the urethra

40. Tube cystostomy
Foley catheter remains in place until animal can urinate through urethra successfully for several days with the catheter occluded
Normal urination occurs around days post-op

41. Tube cystostomy
Tube cystostomy was successful in relieving obstruction in 12 of 15 small ruminants (13 goats, 2 sheep)

42. Tube cystostomy

43. Ischial urethrostomy

44. Urinary bladder marsupialization (cystostomy)
to provide long term resolution of urinary obstruction in small ruminants not intended for slaughter
18/19 goats in one study survived the surgery and at follow up, 15 of 17 owners were satisfied with the procedure

46. Contagious Bovine Pyelonephritis
Corynebacterium renale
Ascending urinary tract infection in cows
Clinical findings
Hematuria, pollakiuria, pyuria
Thickened bladder wall, enlarged ureters, painful kidney

47. Contagious Bovine Pyelonephritis
BUN, creatinine remain normal until late stage
UA – RBCs, WBCs, protein, bacteria
Treatment
Penicillin, high doses for at least 2 weeks
Nephrectomy if only one kidney involved
Prognosis poor

48. Ulcerative posthitis “pizzle rot” C. renale
Common in wethers on high protein diets - increases urea content of urine
Bacteria hydrolyze urea into ammonia which is cytotoxic

49. Ulcerative posthitis Reduce legumes in diet Topical treatment
Penicillin

50. Corynebacterium suis “Thin sow syndrome” Cystitis, pyelonephritis
Venereal transmission from boar
Treatment - penicillin

51. Leptospirosis Multisystemic disease affecting all domestic animals
Organisms shed in urine, infect mucous membranes
Chronic infection causes diffuse interstitial nephritis
Tetracycline
Bacterins

52. Embolic nephritis Secondary to bacteremia or septicemia
Bacteria lodge in small vessels and create infarcts in the kidney
No clinical signs until lesions are large enough to impair renal function
May be incidental finding on necropsy
Treat primary disease with Ab’s

53. Amaranthus retroflexus
Red root pigweed
Perirenal edema and kidney pathology
Toxic principle unknown
Death due to hyperkalemia
No specific treatment
Avoid exposure

54. Oak poisoning Quercus spp. Both oak buds and acorns are toxic
Toxic principle = tannin or gallotanin
Hepatotoxic, nephrotoxic, cause precipitation of proteins
gastroenteritis, hemorrhages, edema, renal lesions (nephrosis)

55. Bracken fern Enzootic hematuria
Transitional cell carcinoma of the bladder

56. Renal amyloidosis Sequella of chronic suppurative process
Deposition of amyloid in a variety of organs with loss of function
Chronic antigenic stimulation
Hypoproteinemia, proteinuria, edema, diarrhea (resembles Johne’s disease)
No treatment

57. Urachal vestiges Persistent or infected urachus
Signs include dysuria, pollakiuria, stranguria
Treatment by surgical removal

58. Congenital diseases Polycystic kidneys Bilateral renal hypoplasia
Hypospadias
Ectopic ureter

59. Neoplasia External genitalia Kidney Bladder Fibropapilloma
Squamous cell carcinoma
Kidney
Lymphosarcoma
Adenoma
Nephroblastoma
Bladder
Transitional cell carcinoma