27 – Salt and Sulfur

Question 1

*How do animals get salt poisoning?

Answer 1

1. Prolonged water deprivation
2. Excess salt intake
   a. High salt poisoning
   b. Formulation errors
   c. Drinking saline water
   d. Oil field brine, butcher shop brine
3. Administration of sodium containing fluids to an animal w/o access to water
   **MOST COMMON=WATER DEPRIVATION

Question 2

*Salt poisoning: species

Answer 2

• All species susceptible
• SWINE more sensitive

Question 3

What are 6 areas to consider with water deprivation?

Answer 3

• Environment (ex. hot weather)
• Availability
• Accessibility (ex. competition)
• Palatability (ex. medication, minerals)
• Welfare
• Physiology (ex. pregnant, lactating)

Question 4

What are some examples of high salt intake in livestock?

Answer 4

• High salt diets in poultry and swine with some water restriction
• High salt in milk replacer of dairy calves (ex. whey)
• Excessive electrolyte supplementation of dairy calves
• Consumption of brine/process water from oil drilling sites
• Free choice to salt following period of no access

Question 5

What are some examples of salt poisoning in companion animals?

Answer 5

• Prolonged water deprivation
• Excessive salt intake
  o Homemade playdough
  o Paintball ingestion
  o Bread dough ingestion
  o Drinking ocean water
  o Salt as an emetic

Question 6

Salt poisoning: mechanism

Answer 6

• Hypernatremia
  o High brain [Na] impairs neuronal energy metabolism
   Failure to pump Na from CNS
• Access to water restored: water moves along osmotic gradient into brain
  o CEREBRAL EDEMA
  o TARGET: CNS

Question 7

Salt poisoning: clinical features

Answer 7

• GI: anorexia, thirst, restlessness, watery diarrhea
• **CNS: ACUTE ONSET OF NEUROLOGICAL SIGNS THAT PROGRESSIVELY WORSEN
  o Wandering, circling, head pressing
  o Tetraparesis, ataxia, hyperesthesia
  o “dog sitting”
  o Recumbency
  o Fasciculations
  o Death due to respiratory failure
  o *PIGS: PRURITUS, CONSTIPATION

Question 8

Salt poisoning: clin path and gross necropsy

Answer 8

• Clin path
  o Hypernatremia
  o High sodium in CSF
  o Pigs: eosinopenia
• Gross
  o Non-specific: GI irritation
  o Dry ingesta
  o Recent rehydration
  o Poultry: anasarca

Question 9

*Salt poisoning: management

Answer 9

• NO decontamination
  1. *SLOW REHYDRATION
  2. Closely monitor patient’s neurological status
• If worsens after fluid therapy: likely worsening of cerebral edema (ex. give mannitol?)
• Frequent measurement of serum NA
• Large animals: intermittent access to water, or HYPERTONIC saline to effect

Question 10

*Salt poisoning: diagnosis

Answer 10

• HISTORY OF WATER DEPRIVATION AND/OR HIGH SALT INTAKE
• Antemortem
  o Chem panel: hypernatremia
  o CSF [Na]
• Postmortem: FRESH brain for [Na+]
  o Alternative: ocular fluid

Question 11

Salt poisoning: prevention

Answer 11

• Always ensure ab libitum access to fresh water
• Mitigate other causes of water loss
• Shade, housing, bedding, ventilation
• Check sulfate and salt concentration of water sources
• Management: avoid overstocking, make sure they know where water is, check water systems are working

Question 12

Sulfur

Answer 12

• Necessary dietary nutrient
• Excess ingestion
  o High sulfur in DIET
  o High sulfates in WATER
  o Excessive fertilizer

Question 13

What are some high sulfur feeds?

Answer 13

• Sulfur accumulating weeds
• High protein feed: alfalfa
• Distiller’s grain
• Molasses
• Brassica species: kale, radishes, turnips, canola, cabbage, broccoli, mustard

Question 14

Sulfur mechanism

Answer 14

• *RUMINANT PROBLEM
• Sulfur in rumen=H2S production=detoxification overwhelmed eructated and inhaled=brain
  o H2S=inhibits cytochrome oxidase in mitochondrial ETC (inhibition of aerobic respiration)
• Takes TIME

Question 15

Sulfur toxicosis: clinical features

Answer 15

• Polioenecphalomalacia
  o Head pressing
  o Blind
  o Circling

Question 16

Sulfur toxicosis: diagnosis

Answer 16

• History
• Suspicion of polio corroborated by FEED AND WATER TESTING RESULTS
• NO tissue test available
• Gross necropsy: rumenitis, alveolitits
• Histo: cerebrocortical necrosis

Question 17

Sulfur toxicosis: management

Answer 17

• Remove animals from suspect feed
• Lack of thiamine therapy
• Symptomatic and supportive care
• Prognosis: variable based on severity

Question 18

Sulfur: prevention

Answer 18

• test diet and water for total dietary sulfur
• restrict access to high sulfur plants (ex. Brassica)

Question 19

Diagnostic approach to polioencephalomalacia (PEM)

Answer 19

• ETIOLOGIES IN RUMINANTS: lead, salt, sulfur, thiamine deficiency
  1. Lead: recent pasture turnout, batteries, time of year
   Live: whole blood
   Dead: liver and kidney
  2. Salt: water deprivation
   Live: hypernatremia
   Dead: fresh brain for Na+
  3. Sulfur: high in ration or water
   Test feed and water (no sulfur tissue test)
  4. Thiamine: response to thiamine therapy