L26: Ruminant Urology (Reuss) Flashcards
Clin path of AKI in SR
- azotemia
- hypoNa/Cl/Ca
- HyperP/Mg
- isosthenuria
Causes of AKI
- drugs
- pigments
- oak
- pigweed
- ethylene glycol
- cholecalciferol rodenticides
- vit. D
- metals
Acute tubular necrosis from NSAIDs: MOA
COX inhibitors –> decreased prostaglandin formation –> enhanced dehydration –> medullary crest necrosis
Pigment nephropathy: MOA
Pigments –> vasoconstriction –> ischemia
Tubular obstruction by protein casts
Hydroxyl radical formation
Cortex most susceptible to damage due to increased blood flow
Hemoglobinuria in SR: causes
- PP hemoglobinuria (due to low intracellular P)
- Bacillary hemoglobinuria (Clostridium)
- Cu toxicity
- Selenium deficiency
- Water intoxication/salt poisoning
Myoglobinuria in SR: causes
- White Muscle dz (vit. E, Se def.)
- Cassia occidentalis (Wild coffee) –> m. Degeneration
Oak Poisoning
- cause of AKI
- tannins hydrolyzed in rumen to gallic acid
- CS: constipation, melena, tenesmus
- azotemia, proteinuria, glucosuria
- ascites, hydropericardium, hydrothorax
- Tx: supportive, prevention
- SRs have tanninase in rumen!
Pigweed Toxicity
- cause of AKI in cattle and swine
- plant oxalates chelate calcium
- CS: weakness, tremor, ataxia, recumbency, “perirenal edema”
- azotemia, proteinuria, hyperK
- high mortality
Lepto
Cause of AKI:
- renal vascular endothelial damage –> hypoxia, interstitial nephritis –> hemoglobinuria
- CS: fever, abortion, mastitis, meningitis
- most common in young animals w/ access to stagnant water
Dx/Tx of lepto
Dx: paired titers, urine PCR/serology
Tx: penicillin, ampicillin, ceftiofur, tetracycline
Vaccinate
CS of AKI
- oliguria, PU
- anorexia, diarrhea, bloat, m. Weakness
- epistaxis, ammonia breath
- bitter milk
Causes of urolithiasis
- young castrated males (no testosterone)
- high concentrate feed
- estrogenic subtances and Vit. A can be a nidus
- supersaturation (dec. H2O consumption)
Types of stones and when they form
1) Struvite - alkaline pH, high P, high Mg due to pelleted diets
2) Ca phosphate - alkaline urine
3) Ca carbonate - legume diets
4) Silicate - high silica content in grass (Western US)
5) Oxalate - acidic urine (from eating apples, sweet potatoes, pigweed, fescue)
CS of urethral obstruction
- restless, treading
- vocalize
- stranguria, dysuria, hematuria
- rectal prolapse
Small ruminants most commonly get calculi obstruction where?**
Neck of bladder
Urethral process
Cattle most commonly get calculi obstruction where?**
Sigmoid flexure
Urethral rupture –> water belly
Bladder rupture –> ?
Abd. Distension, anorexia, colic
More common
Clin path of urolithiasis
Azotemia
Hemoconcentration
HypoNa, HypoCl
Hyper P/K/Mg
Peritoneal: serum Cr > 2:1 if bladder ruptured
Medical tx of urolithiasis
0.9% NaCl + Ca
Walpoles’ solution to acidify bladder and dissolve stones (pH 4.5)
-30% recurrence
Amputate urethral process (66% success)
Sx options for urolithiasis
1) Perineal/ischial urethrostomy (short term solution only for feedlot steer)
2) Tube cystotomy
- best for breeding animals
- need close management
3) BL marsupialization +/- urethrotomy
Prevention of urolithiasis
- determine composition of stone
- Ca:P > 2:1
- increase forage
- acidify urine
- encourage water consumption
- delay castration
- avoid estrogenic growth stimulants
- ammonium chloride (increases excretion of Cl AND Ca, so may predispose to Ca phosphate stones)
- anionic salts
Pizzle Rot
- due to Corynebacterium renale
- grows in high urinary urea env. 2ary to high protein diet
- hydrolyzes urea to ammonia –> ulceration
- can progress to internal form (adhesions, distorted vulvar conformation)
- contagious
- tx with abx, reduce protein
Pyelonephritis agents
1) Corynebacterium renale:
- contagious (trans. Via direct, venereal, iatrogenic)
2) E. Coli
- ascending
3) hematogenous Salmonella, Clostridium, A. Pyogenes, Staph aureus
CS of pyelonephritis
- colic, arched, fever, depressed, dec. milk yield
- blood, pus, crystals on vulva
Dx/Tx of pyelonephritis
- enlarged painful kidney
- inc. white count, fibrinogen, globulin
- azotemia
- hematuria, proteinuria, bacteriuria, leukocyte casts
Tx: penicillin, ceftiofur >3 wks, quarantine infected
