Top 20 Vet Toxicoses Part 1

What are common clinical signs of lead toxicosis in cattle?

Ataxia, blindness, eyelid twitching, salivation, jaw chomping, bruxism, muscle tremors, and convulsions.

What is the treatment for lead toxicosis in animals?

Calcium disodium edetate and thiamine.

What is a classic symptom of selenium toxicosis in grazing animals?

Weird behavior, respiratory trouble, and tachycardia.

What does high selenium concentration in feed indicate?

Potential selenium toxicosis in animals.

What clinical signs indicate copper toxicosis?

Acute gastroenteritis with diarrhea and vomiting, and chronic acute hemolytic crisis.

What is a common diagnostic method for zinc toxicosis?

Radiographs showing radiodense foreign bodies and blood zinc concentration.

What serious consequence can result from zinc toxicosis in foals?

Epiphyseal swelling and lameness.

What are the signs of fluoride toxicosis in livestock?

Salivation, sweating, muscle weakness, and ventricular tachycardia.

What is the treatment for acute fluoride toxicosis?

Decrease absorption via IV calcium gluconate or oral magnesium hydroxide.

What pathophysiological effect does fluoride have in the body?

It alters intracellular metabolism of essential metals such as Mg, Mn, Fe, Cu, and Zn.

Acute lead toxicosis CS in ruminants?

Acute:

1. Ataxia, blindness, eyelid twitching

2. Salivation

3. Jaw chomping

4. Bruxism

5. Muscle tremors

Subacute & Chronic lead toxicosis CS in ruminants?

Subacute (sheep and older cows):

1. Anorexia, rumen stasis, colic

2. Constipation then diarrhea

3. Blidness, head pressing, hyperesthesia, incoordination

4. Bruxism

Chronic:

1. Dysphagia

2. Aspiration pneumonia

Lead toxicosis dogs CS?

1. Anorexia, vomiting, diarrhea, constipation

2. Anxiety, barking

3. Salivation

4. Blindness, ataxia

5. Muscle spasms

6. Opisthotonus, convulsions

Lead toxicosis CS in horses?

Chronic WL, dysphagia, diarrhea, roaring

CBC and blood findings in lead toxicosis?

1. Blood lead conc. >0.05-0.10ppm

2. CBC: Anemia, anisocytosis, poikilocytosis, polychromasia, basophilic stippling, metarubricytosis, hypochromia

Lead poisoning Tx?

All animals: Ca disodium edetate and thiamine

Dogs: D penicillamine or succimer

What pathophysiologic changes does lead toxicosis cause>

1. Capillary damage/edema

2. Irritation

3. Immune suppression

4. Nephrotoxic

5. Toxic to hematopoietic system

6. Teratogenic

Which animals are most affected by selenium toxicosis?

Grazing animals, but most are susceptible

Acute CS of selenium toxicosis?

1. Weird behavior

2. Resp. trouble and tachycardia

3. Frothy nasal discharge

4. GI upset

5. Sudden death

Subacute selenium toxicosis CS?

Pigs:

1. Ataxia

2. Paraparesis followed by tetraplegia

3. Poor hooves

4. Alopecia

Chronic selenium tox CS?

1. Rough/brittle haircoat

2. Poor hooves/laminitis

3. Weakness, anorexia

Selenium tox Dx?

1. High selenium conc. in feed

2. High selenium conc. in blood/tissues

Selenium tox Tx?

Acute: N acetylcysteine to improve systemic glutathione levels

Chronic: High protein diet (to bind selenium) or add arsenic salt (enhances biliary excretion)

Selenium tox. pathophysiology?

1. Directly inhibits cellular oxidation/reduction reactions

2. Increases O2 free radicals causing tissue damage

3. Alters protein formations/cellular bonds, affecting their function

Copper tox CS?

Acute (less common):

1. Gastroenteritis with diarrhea, vomiting

2. Pain

3. Shock

Chronic:

1. Acute hemolytic crisis

2. Weakness

3. Icterus, hemoglobinuria

4. Colic

5. ± Renal failure

Which animals are affected by copper tox?

Sheep and dogs esp., but others can be affected

Copper tox Dx?

1. High copper levels in blood, liver and kidney

2. See gun metal colored kidneys and blue green ingesta on necropsy

Copper tox Tx?

1. Penicillamine or ammonium tetrathiomolybdate to increase copper excretion

2. Vit C as antioxidant

Copper tox pathophysiology?

Affects the hematopoietic system, liver and GIT

1. Lipid peroxidation

2. IV hemolysis

3. GI irritation

Copper tox prognosis?

Poor, bendlingons have inherited sensitivity to increased copper levels

What can lead to increased copper levels?

Low dietary sulfur or molybdenum leads to increased absorption and decreased excretion

Zn tox CS?

1. Anorexia

2. Vomiting, diarrhea

3. Lethargy

4. Icterus and hemoglobinuria (due to IV hemolysis)

5. Cardiac arrhythmias

6. Seizures

7. Foals may have epiphyseal swelling and lameness

Zn tox pathophysiology?

Affects the GIT, hematopoietic system, cardiac and CNS

1. Low gastric pH causes release of caustic Zn salts which irritate and interfere with cellular metabolism

2. Zn is an essential trace mineral

Where can Zn be found?

In coating, supplements, batteries, paints, creams, Zn coated pennies.

Zn tox Dx?

1. Ro: see radio dense FB

2. CBC: anemia, spherocytosis, heinz body formation

3. Blood Zn conc.

Zn tox Tx?

1. Remove Zn source

2. Diuresis

3. Supportive care

4. Chelation therapy with Ca EDTA is contraversial

Fluoride tox acute CS?

1. Salivation, sweating

2. Restlessness

3. Anorexia, gastroenteritis

4. Muscle weakness, stiffness

5. Dyspnea

6. Ventricular tachycardia

7. Clonic convulsions, depression, death

Chronic fluoride tox CS?

1. Poor weight gain, unthrifty

2. Dental: mottled, chalky, pitted and stained enamel with excessive and uneven wear

3. Skeletal: stiffness, severe lameness, abnormal hoof growth, exostoses, periosteal hyperostosis on ribs

Fluoride tox Dx?

1. Hx of exposure and typical CS

2. Urinary and serum fluoride conc (tricky because of rapid elimination)

3. Radiography: periosteal hyperostosis, exostooooooooses

Fluoride tox Tx?

1. Acute: decrease absorption via IV Ca gluconate or oral Mg hydroxide or milk

2. Chronic: none

Fluoride tox pathophysiology?

Fluoride alters IC metabolism of essential metals like Mg, Mn, Fe, Cu and Zn

Fluoride tox prevention?

Supplementation with Ca carbonate, aluminum salts, Mg metasilicate, or boron to decrease absorption and increase excretion