Selenium Flashcards
Disease associated with deficiency
- White muscle disease in lambs, calves and foals
- hepatosis dietetica in pigs
- exudative diathesis in chicks
- nutritional pancreatic atrophy in chickens
- porcine stress syndrome
Low sodium areas
Northeast, East coast, florida, washington and half of west coast
Use
- feed supplements
- antioxidant supplement
- medicated shampoo for dermatitis
Source
- Cattle, sheep and horses get it from plants
- swine and poultry get grains from selenium rich soil
Seleniferous plants
- Obligate accumulators
- Facultative accumulators
- passive accumulators- normal crops
- unpalatable and have a bad odor
Toxicosis
- Overdosage
- contaminated water
- improper use of shampoos
Properties
- Essential trace element
- Similar to sulfur and arsenic
- combines with -SH
- is a component of glutathione peroxidase
- irritant to mucous membranes
3 oxidation states
- selenate +6
- selenite +4
- selenide -2
How does selenium act as an antioxidant
- prevents cellular degeneration with vitamin E
Toxicity most to least
organic –> selenate–> selenite –> selenide –> synthetic
How is toxicity reduced
- high protein diet
- ingestions of other elements that bind Se (copper)
Toxicokinetics
- absorbed from small intestine
- organic is more absorbed than other states
- elemental Se is not absorbed/ soluble in water
- distributed throughout the body
- can cross placenta and is excreted in milk
Where will you find high conc. of Se
- Hair and hoof
What increases biliary excretion
arsenic
MOA
- Irritant of GI
- depletion of tissue glutathione
- replaces sulfur in amino acids = fucked up proteins
- decrease ATP
- decrease tissue ascorbic acid
Death in acute and subacute is due to
- respiratory insufficiency from pulmonary edema and hemorrhage
Death in chronic cases is due to
- starvation and thirst from weakness, lameness and blindness
Acute CS from oral ingestion
- onset can be a few hours to days
- GI signs
- Respiratory signs
- bloody froth from nose
- cyanosis
- fever, polyuria, mydriasis and bad gait
- death in hours
Acute CS from parenteral administration
neurological signs
mydriasis
incoordination
Subacute CS in cattle
- Blind staggers
- Stage 1: poor appetite, wandering, circling, normal respiration and temp
- Stage 2: depression, incoordination, foreleg weakness, walking on knees, anorexia
- Stage 3: colic, hypothermia, emaciation, clouded corneas, paresis, coma, death
Subacute CS in swine
- porcine focal symmetrical poliomyelomalacia
- neurologic signs
- alopecia, hoof abnormalities and separation of the hoof
Chronic toxicosis (alkali disease)
- Rough hair coat
- hoof deformities
- joint issues
- partial blindness, anemia, lethargy, emaciation, infertility and birth defects
Lesions in acute cases
- Hemorrhagic GI, congestion of organs, pulmonary edema, hydrothorax
- gut contents smell like rotten garlic or horseradish
Lab results for acute
- Elevated selenium in blood, kidney and liver
