4.6 Lab

Question 1

acute signs of lead toxicosis

Answer 1

• Gastropathy
• Lethargy, anorexia, anemia
• Encephalopathy
• Nephropathy

Question 2

chronic signs of lead toxicosis

Answer 2

• Weight loss
• Impaired bone growth
• Peripheral neuropathy in birds
• Impaired brain development in children

Question 3

Effects of lead on erythropoiesis

Answer 3

Lead binds to RBCs Impairs maturation Mild anemia

Reduced Fe incorporation Impaired catabolism of RNA

=>basophilic stippling of RBS, metarubricytes in circulation may be seen

Question 4

Causes of polioencephalomalacia (PEM) = > what metal? signs?

Answer 4

acute lead poisoning

Depression
Head pressing
Blindness
Cerebral edema
Flattened gyri
Necrosis
Malacia

Question 5

what is a common finding in bird lead toxicity cases?

Answer 5

Peripheral neuropathy due to demyelination

Lead poisoning in waterfowl and raptors leads to muscle weakness, wasting, inability to feed, etc
In these birds, chronic lead poisoning injures Schwann cells and this leads to demyelination with peripheral motor nerve dysfunction

Question 6

what can lead poisoning do to the kidneys? what will this look like?

Answer 6

Lead poisoning: Renal tubular necrosis

-Swollen, pale kidney
-Intranuclear inclusions in renal tubules (NON VIRAL inclusions)

Question 7

do cows always show signs of high lead levels

Answer 7

can be asymptomatic

Question 8

clinical signs of lead toxicosis in cats?

Answer 8

 Vomiting and diarrhea
 Dehydrated, pale mucus membranes

 Prolapsed third eyelids
 Swaying gait, fine tremor

 Hypersalivating, hyperesthetic

Question 9

lab and radiograph findings in cats with lead toxicosis

Answer 9

Laboratory findings
 Mild anemia
 Elevated ALT and Alk Phos
-serum improtant test too

Radiographic Findings
Megaesophagus - Midge

Question 10

how to treat lead toxicity in cats and how to react to the news of environmental contamination

Answer 10

Immediate action
 Wash the cats to remove deposits
> The cat’s have likely been exposed to dust from lead paint, and have been grooming it off themselves
 Anti-emetic, gastroprotectants
 IV fluids for dehydration
 Chelation: sodium calcium EDTA 25mg/kg, 4x/day

Question 11

what is chelation? what is its purpose?

Answer 11

A product that binds with a metal (such as lead or iron) in the body > metal loses its chemical effect (such as toxicity or physiological activity)

Question 12

selenium intoxication in pigs clinical signs. PM lesion?

Answer 12

Afebrile, paralysis, acute mortality
(>50% dead in 48 hours)
>posterior paralysis, dog-sitting posture

-PM necrosis of grey matter of spinal cord

Question 13

important property of seleium in proper dose?

Answer 13

essential trace mineral, important antioxidant properties

Question 14

acute selenium toxicosis in horses signs

Answer 14

Spontaneous death!
 Central nervous system disturbance
> Hyperexcitability, sweating, ataxia, tachycardia, dyspnea, pyrexia, rapid death
 Muscle hemorrhages, myocardial necrosis
 Mean selenium conc >6 mg/kg in liver, kidneys

Question 15

excess Se causes:

Answer 15

Acute mortality, Posterior paralysis, Alkali disease

Question 16

Se deficiency causes:

Answer 16

Low glutathione peroxidase, Lipid peroxidation,
“White muscle disease”

Question 17

how does chronic selenium toxicosis manifest?

Answer 17

 Incorporated into developing keratin – replaces sulfur
 Deformed hair, hoof, epidermis
 Dull dry coat
 Joint pain
 Emaciation
 Reproductive losses

Question 18

CO mechanism of toxicosis and tell-tale sign

Answer 18

Hb binds CO with high affinity (24x >O2)
➝ CO-Hb
CO stabilizes binding Hb to O2 (Haldane effect)
CO-Hb is cherry red and also has effects that blood transfusions do not correct
(poisons other heme proteins)